Issue #1829 - Revert "Issue #1751 -- Remove cocoa and uikit widget support code"

This reverts commit 08da125d9cc6eea0bc514023e3a75efd64587259.

165 files changed, 42109 insertions, 4 deletions

diff --git a/widget/cocoa/ComplexTextInputPanel.h b/widget/cocoa/ComplexTextInputPanel.h
new file mode 100644
index 0000000000..648e6d9114
--- /dev/null
+++ b/widget/cocoa/ComplexTextInputPanel.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2009 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Modified by Josh Aas of Mozilla Corporation.
+ */
+
+#ifndef ComplexTextInputPanel_h_
+#define ComplexTextInputPanel_h_
+
+#include "nsString.h"
+#include "npapi.h"
+
+class ComplexTextInputPanel
+{
+public:
+  static ComplexTextInputPanel* GetSharedComplexTextInputPanel();
+  virtual void PlacePanel(int32_t x, int32_t y) = 0; // Bottom left coordinate of plugin in screen coords
+  virtual void InterpretKeyEvent(void* aEvent, nsAString& aOutText) = 0;
+  virtual bool IsInComposition() = 0;
+  virtual void* GetInputContext() = 0;
+  virtual void CancelComposition() = 0;
+
+protected:
+  virtual ~ComplexTextInputPanel() {};
+};
+
+#endif // ComplexTextInputPanel_h_
diff --git a/widget/cocoa/ComplexTextInputPanel.mm b/widget/cocoa/ComplexTextInputPanel.mm
new file mode 100644
index 0000000000..a4b58955e2
--- /dev/null
+++ b/widget/cocoa/ComplexTextInputPanel.mm
@@ -0,0 +1,261 @@
+/*
+ * Copyright (C) 2009 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ *
+ * Modified by Josh Aas of Mozilla Corporation.
+ */
+
+#import "ComplexTextInputPanel.h"
+
+#import <Cocoa/Cocoa.h>
+
+#include <algorithm>
+#include "mozilla/Preferences.h"
+#include "nsChildView.h"
+
+using namespace mozilla;
+
+extern "C" OSStatus TSMProcessRawKeyEvent(EventRef anEvent);
+
+#define kInputWindowHeight 20
+
+@interface ComplexTextInputPanelImpl : NSPanel {
+  NSTextView *mInputTextView;
+}
+
++ (ComplexTextInputPanelImpl*)sharedComplexTextInputPanelImpl;
+
+- (NSTextInputContext*)inputContext;
+- (void)interpretKeyEvent:(NSEvent*)event string:(NSString**)string;
+- (void)cancelComposition;
+- (BOOL)inComposition;
+
+// This places the text input panel fully onscreen and below the lower left
+// corner of the focused plugin.
+- (void)adjustTo:(NSPoint)point;
+
+@end
+
+@implementation ComplexTextInputPanelImpl
+
++ (ComplexTextInputPanelImpl*)sharedComplexTextInputPanelImpl
+{
+  static ComplexTextInputPanelImpl *sComplexTextInputPanelImpl;
+  if (!sComplexTextInputPanelImpl)
+    sComplexTextInputPanelImpl = [[ComplexTextInputPanelImpl alloc] init];
+  return sComplexTextInputPanelImpl;
+}
+
+- (id)init
+{
+  // In the original Apple code the style mask is given by a function which is not open source.
+  // What could possibly be worth hiding in that function, I do not know.
+  // Courtesy of gdb: stylemask: 011000011111, 0x61f
+  self = [super initWithContentRect:NSZeroRect styleMask:0x61f backing:NSBackingStoreBuffered defer:YES];
+  if (!self)
+    return nil;
+
+  // Set the frame size.
+  NSRect visibleFrame = [[NSScreen mainScreen] visibleFrame];
+  NSRect frame = NSMakeRect(visibleFrame.origin.x, visibleFrame.origin.y, visibleFrame.size.width, kInputWindowHeight);
+
+  [self setFrame:frame display:NO];
+
+  mInputTextView = [[NSTextView alloc] initWithFrame:[self.contentView frame]];        
+  mInputTextView.autoresizingMask = NSViewWidthSizable | NSViewHeightSizable | NSViewMaxXMargin | NSViewMinXMargin | NSViewMaxYMargin | NSViewMinYMargin;
+
+  NSScrollView* scrollView = [[NSScrollView alloc] initWithFrame:[self.contentView frame]];
+  scrollView.documentView = mInputTextView;
+  self.contentView = scrollView;
+  [scrollView release];
+
+  [self setFloatingPanel:YES];
+
+  [[NSNotificationCenter defaultCenter] addObserver:self
+                                           selector:@selector(keyboardInputSourceChanged:)
+                                               name:NSTextInputContextKeyboardSelectionDidChangeNotification
+                                             object:nil];
+
+  return self;
+}
+
+- (void)dealloc
+{
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  
+  [mInputTextView release];
+  
+  [super dealloc];
+}
+
+- (void)keyboardInputSourceChanged:(NSNotification *)notification
+{
+  static int8_t sDoCancel = -1;
+  if (!sDoCancel || ![self inComposition]) {
+    return;
+  }
+  if (sDoCancel < 0) {
+    bool cancelComposition = false;
+    static const char* kPrefName =
+      "ui.plugin.cancel_composition_at_input_source_changed";
+    nsresult rv = Preferences::GetBool(kPrefName, &cancelComposition);
+    NS_ENSURE_SUCCESS(rv, );
+    sDoCancel = cancelComposition ? 1 : 0;
+  }
+  if (sDoCancel) {
+    [self cancelComposition];
+  }
+}
+
+- (void)interpretKeyEvent:(NSEvent*)event string:(NSString**)string
+{
+  *string = nil;
+
+  if (![[mInputTextView inputContext] handleEvent:event]) {
+    return;
+  }
+
+  if ([mInputTextView hasMarkedText]) {
+    // Don't show the input method window for dead keys
+    if ([[event characters] length] > 0) {
+      [self orderFront:nil];
+    }
+    return;
+  } else {
+    [self orderOut:nil];
+
+    NSString *text = [[mInputTextView textStorage] string];
+    if ([text length] > 0) {
+      *string = [[text copy] autorelease];
+    }
+  }
+
+  [mInputTextView setString:@""];
+}
+
+- (NSTextInputContext*)inputContext
+{
+  return [mInputTextView inputContext];
+}
+
+- (void)cancelComposition
+{
+  [mInputTextView setString:@""];
+  [self orderOut:nil];
+}
+
+- (BOOL)inComposition
+{
+  return [mInputTextView hasMarkedText];
+}
+
+- (void)adjustTo:(NSPoint)point
+{
+  NSRect selfRect = [self frame];
+  NSRect rect = NSMakeRect(point.x,
+                           point.y - selfRect.size.height,
+                           500,
+                           selfRect.size.height);
+
+  // Adjust to screen.
+  NSRect screenRect = [[NSScreen mainScreen] visibleFrame];
+  if (rect.origin.x < screenRect.origin.x) {
+    rect.origin.x = screenRect.origin.x;
+  }
+  if (rect.origin.y < screenRect.origin.y) {
+    rect.origin.y = screenRect.origin.y;
+  }
+  CGFloat xMostOfScreen = screenRect.origin.x + screenRect.size.width;
+  CGFloat yMostOfScreen = screenRect.origin.y + screenRect.size.height;
+  CGFloat xMost = rect.origin.x + rect.size.width;
+  CGFloat yMost = rect.origin.y + rect.size.height;
+  if (xMostOfScreen < xMost) {
+    rect.origin.x -= xMost - xMostOfScreen;
+  }
+  if (yMostOfScreen < yMost) {
+    rect.origin.y -= yMost - yMostOfScreen;
+  }
+
+  [self setFrame:rect display:[self isVisible]];
+}
+
+@end
+
+class ComplexTextInputPanelPrivate : public ComplexTextInputPanel
+{
+public:
+  ComplexTextInputPanelPrivate();
+
+  virtual void InterpretKeyEvent(void* aEvent, nsAString& aOutText);
+  virtual bool IsInComposition();
+  virtual void PlacePanel(int32_t x, int32_t y);
+  virtual void* GetInputContext() { return [mPanel inputContext]; }
+  virtual void CancelComposition() { [mPanel cancelComposition]; }
+
+private:
+  ~ComplexTextInputPanelPrivate();
+  ComplexTextInputPanelImpl* mPanel;
+};
+
+ComplexTextInputPanelPrivate::ComplexTextInputPanelPrivate()
+{
+  mPanel = [[ComplexTextInputPanelImpl alloc] init];
+}
+
+ComplexTextInputPanelPrivate::~ComplexTextInputPanelPrivate()
+{
+  [mPanel release];
+}
+
+ComplexTextInputPanel*
+ComplexTextInputPanel::GetSharedComplexTextInputPanel()
+{
+  static ComplexTextInputPanelPrivate *sComplexTextInputPanelPrivate;
+  if (!sComplexTextInputPanelPrivate) {
+    sComplexTextInputPanelPrivate = new ComplexTextInputPanelPrivate();
+  }
+  return sComplexTextInputPanelPrivate;
+}
+
+void
+ComplexTextInputPanelPrivate::InterpretKeyEvent(void* aEvent, nsAString& aOutText)
+{
+  NSString* textString = nil;
+  [mPanel interpretKeyEvent:(NSEvent*)aEvent string:&textString];
+
+  if (textString) {
+    nsCocoaUtils::GetStringForNSString(textString, aOutText);
+  }
+}
+
+bool
+ComplexTextInputPanelPrivate::IsInComposition()
+{
+  return !![mPanel inComposition];
+}
+
+void
+ComplexTextInputPanelPrivate::PlacePanel(int32_t x, int32_t y)
+{
+  [mPanel adjustTo:NSMakePoint(x, y)];
+}
diff --git a/widget/cocoa/CustomCocoaEvents.h b/widget/cocoa/CustomCocoaEvents.h
new file mode 100644
index 0000000000..0043f0d695
--- /dev/null
+++ b/widget/cocoa/CustomCocoaEvents.h
@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * This file defines constants to be used in the "subtype" field of
+ * NSApplicationDefined type NSEvents.
+ */
+
+#ifndef WIDGET_COCOA_CUSTOMCOCOAEVENTS_H_
+#define WIDGET_COCOA_CUSTOMCOCOAEVENTS_H_
+
+// Empty event, just used for prodding the event loop into responding.
+const short kEventSubtypeNone = 0;
+// Tracer event, used for timing the event loop responsiveness.
+const short kEventSubtypeTrace = 1;
+
+#endif /* WIDGET_COCOA_CUSTOMCOCOAEVENTS_H_ */
diff --git a/widget/cocoa/GfxInfo.h b/widget/cocoa/GfxInfo.h
new file mode 100644
index 0000000000..05bdad158b
--- /dev/null
+++ b/widget/cocoa/GfxInfo.h
@@ -0,0 +1,95 @@
+/* vim: se cin sw=2 ts=2 et : */
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef __mozilla_widget_GfxInfo_h__
+#define __mozilla_widget_GfxInfo_h__
+
+#include "GfxInfoBase.h"
+
+#include "nsString.h"
+
+namespace mozilla {
+namespace widget {
+
+class GfxInfo : public GfxInfoBase
+{
+public:
+
+  GfxInfo();
+  // We only declare the subset of nsIGfxInfo that we actually implement. The
+  // rest is brought forward from GfxInfoBase.
+  NS_IMETHOD GetD2DEnabled(bool *aD2DEnabled) override;
+  NS_IMETHOD GetDWriteEnabled(bool *aDWriteEnabled) override;
+  NS_IMETHOD GetDWriteVersion(nsAString & aDwriteVersion) override;
+  NS_IMETHOD GetCleartypeParameters(nsAString & aCleartypeParams) override;
+  NS_IMETHOD GetAdapterDescription(nsAString & aAdapterDescription) override;
+  NS_IMETHOD GetAdapterDriver(nsAString & aAdapterDriver) override;
+  NS_IMETHOD GetAdapterVendorID(nsAString & aAdapterVendorID) override;
+  NS_IMETHOD GetAdapterDeviceID(nsAString & aAdapterDeviceID) override;
+  NS_IMETHOD GetAdapterSubsysID(nsAString & aAdapterSubsysID) override;
+  NS_IMETHOD GetAdapterRAM(nsAString & aAdapterRAM) override;
+  NS_IMETHOD GetAdapterDriverVersion(nsAString & aAdapterDriverVersion) override;
+  NS_IMETHOD GetAdapterDriverDate(nsAString & aAdapterDriverDate) override;
+  NS_IMETHOD GetAdapterDescription2(nsAString & aAdapterDescription) override;
+  NS_IMETHOD GetAdapterDriver2(nsAString & aAdapterDriver) override;
+  NS_IMETHOD GetAdapterVendorID2(nsAString & aAdapterVendorID) override;
+  NS_IMETHOD GetAdapterDeviceID2(nsAString & aAdapterDeviceID) override;
+  NS_IMETHOD GetAdapterSubsysID2(nsAString & aAdapterSubsysID) override;
+  NS_IMETHOD GetAdapterRAM2(nsAString & aAdapterRAM) override;
+  NS_IMETHOD GetAdapterDriverVersion2(nsAString & aAdapterDriverVersion) override;
+  NS_IMETHOD GetAdapterDriverDate2(nsAString & aAdapterDriverDate) override;
+  NS_IMETHOD GetIsGPU2Active(bool *aIsGPU2Active) override;
+
+  using GfxInfoBase::GetFeatureStatus;
+  using GfxInfoBase::GetFeatureSuggestedDriverVersion;
+  using GfxInfoBase::GetWebGLParameter;
+
+  virtual nsresult Init() override;
+
+#ifdef DEBUG
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_NSIGFXINFODEBUG
+#endif
+
+  virtual uint32_t OperatingSystemVersion() override { return mOSXVersion; }
+
+  nsresult FindMonitors(JSContext* cx, JS::HandleObject array) override;
+
+protected:
+
+  virtual ~GfxInfo() {}
+
+  virtual nsresult GetFeatureStatusImpl(int32_t aFeature,
+                                        int32_t *aStatus,
+                                        nsAString & aSuggestedDriverVersion,
+                                        const nsTArray<GfxDriverInfo>& aDriverInfo,
+                                        nsACString &aFailureId,
+                                        OperatingSystem* aOS = nullptr) override;
+  virtual const nsTArray<GfxDriverInfo>& GetGfxDriverInfo() override;
+
+private:
+
+  void GetDeviceInfo();
+  void GetSelectedCityInfo();
+  void AddCrashReportAnnotations();
+
+  nsString mAdapterRAMString;
+  nsString mDeviceID;
+  nsString mDriverVersion;
+  nsString mDriverDate;
+  nsString mDeviceKey;
+
+  nsString mAdapterVendorID;
+  nsString mAdapterDeviceID;
+
+  uint32_t mOSXVersion;
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif /* __mozilla_widget_GfxInfo_h__ */
diff --git a/widget/cocoa/GfxInfo.mm b/widget/cocoa/GfxInfo.mm
new file mode 100644
index 0000000000..97bb4c8324
--- /dev/null
+++ b/widget/cocoa/GfxInfo.mm
@@ -0,0 +1,426 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <OpenGL/OpenGL.h>
+#include <OpenGL/CGLRenderers.h>
+
+#include "mozilla/ArrayUtils.h"
+
+#include "GfxInfo.h"
+#include "nsUnicharUtils.h"
+#include "nsCocoaFeatures.h"
+#include "mozilla/Preferences.h"
+#include <algorithm>
+
+#import <Foundation/Foundation.h>
+#import <IOKit/IOKitLib.h>
+#import <Cocoa/Cocoa.h>
+
+using namespace mozilla;
+using namespace mozilla::widget;
+
+#ifdef DEBUG
+NS_IMPL_ISUPPORTS_INHERITED(GfxInfo, GfxInfoBase, nsIGfxInfoDebug)
+#endif
+
+GfxInfo::GfxInfo()
+{
+}
+
+static OperatingSystem
+OSXVersionToOperatingSystem(uint32_t aOSXVersion) {
+  switch (nsCocoaFeatures::ExtractMajorVersion(aOSXVersion)) {
+    case 10:
+      switch (nsCocoaFeatures::ExtractMinorVersion(aOSXVersion)) {
+        case 6:
+          return OperatingSystem::OSX10_6;
+        case 7:
+          return OperatingSystem::OSX10_7;
+        case 8:
+          return OperatingSystem::OSX10_8;
+        case 9:
+          return OperatingSystem::OSX10_9;
+        case 10:
+          return OperatingSystem::OSX10_10;
+        case 11:
+          return OperatingSystem::OSX10_11;
+        case 12:
+          return OperatingSystem::OSX10_12;
+        case 13:
+          return OperatingSystem::OSX10_13;
+        case 14:
+          return OperatingSystem::OSX10_14;
+        case 15:
+          return OperatingSystem::OSX10_15;
+        case 16:
+          // Depending on the SDK version, we either get 10.16 or 11.0.
+          // Normalize this to 11.0.
+          return OperatingSystem::OSX11_0;
+        default:
+          break;
+      }
+      break;
+    case 11:
+      switch (nsCocoaFeatures::ExtractMinorVersion(aOSXVersion)) {
+        case 0:
+          return OperatingSystem::OSX11_0;
+        default:
+          break;
+      }
+      break;
+  }
+
+  return OperatingSystem::Unknown;
+}
+// The following three functions are derived from Chromium code
+static CFTypeRef SearchPortForProperty(io_registry_entry_t dspPort,
+                                       CFStringRef propertyName)
+{
+  return IORegistryEntrySearchCFProperty(dspPort,
+                                         kIOServicePlane,
+                                         propertyName,
+                                         kCFAllocatorDefault,
+                                         kIORegistryIterateRecursively |
+                                         kIORegistryIterateParents);
+}
+
+static uint32_t IntValueOfCFData(CFDataRef d)
+{
+  uint32_t value = 0;
+
+  if (d) {
+    const uint32_t *vp = reinterpret_cast<const uint32_t*>(CFDataGetBytePtr(d));
+    if (vp != NULL)
+      value = *vp;
+  }
+
+  return value;
+}
+
+void
+GfxInfo::GetDeviceInfo()
+{
+  io_registry_entry_t dsp_port = CGDisplayIOServicePort(kCGDirectMainDisplay);
+  CFTypeRef vendor_id_ref = SearchPortForProperty(dsp_port, CFSTR("vendor-id"));
+  if (vendor_id_ref) {
+    mAdapterVendorID.AppendPrintf("0x%04x", IntValueOfCFData((CFDataRef)vendor_id_ref));
+    CFRelease(vendor_id_ref);
+  }
+  CFTypeRef device_id_ref = SearchPortForProperty(dsp_port, CFSTR("device-id"));
+  if (device_id_ref) {
+    mAdapterDeviceID.AppendPrintf("0x%04x", IntValueOfCFData((CFDataRef)device_id_ref));
+    CFRelease(device_id_ref);
+  }
+}
+
+nsresult
+GfxInfo::Init()
+{
+  nsresult rv = GfxInfoBase::Init();
+
+  // Calling CGLQueryRendererInfo causes us to switch to the discrete GPU
+  // even when we don't want to. We'll avoid doing so for now and just
+  // use the device ids.
+
+  GetDeviceInfo();
+
+  AddCrashReportAnnotations();
+
+  mOSXVersion = nsCocoaFeatures::macOSVersion();
+
+  return rv;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetD2DEnabled(bool *aEnabled)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetDWriteEnabled(bool *aEnabled)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString DWriteVersion; */
+NS_IMETHODIMP
+GfxInfo::GetDWriteVersion(nsAString & aDwriteVersion)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString cleartypeParameters; */
+NS_IMETHODIMP
+GfxInfo::GetCleartypeParameters(nsAString & aCleartypeParams)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterDescription; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDescription(nsAString & aAdapterDescription)
+{
+  aAdapterDescription.AssignLiteral("");
+  return NS_OK;
+}
+
+/* readonly attribute DOMString adapterDescription2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDescription2(nsAString & aAdapterDescription)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterRAM; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterRAM(nsAString & aAdapterRAM)
+{
+  aAdapterRAM = mAdapterRAMString;
+  return NS_OK;
+}
+
+/* readonly attribute DOMString adapterRAM2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterRAM2(nsAString & aAdapterRAM)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterDriver; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriver(nsAString & aAdapterDriver)
+{
+  aAdapterDriver.AssignLiteral("");
+  return NS_OK;
+}
+
+/* readonly attribute DOMString adapterDriver2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriver2(nsAString & aAdapterDriver)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterDriverVersion; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverVersion(nsAString & aAdapterDriverVersion)
+{
+  aAdapterDriverVersion.AssignLiteral("");
+  return NS_OK;
+}
+
+/* readonly attribute DOMString adapterDriverVersion2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverVersion2(nsAString & aAdapterDriverVersion)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterDriverDate; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverDate(nsAString & aAdapterDriverDate)
+{
+  aAdapterDriverDate.AssignLiteral("");
+  return NS_OK;
+}
+
+/* readonly attribute DOMString adapterDriverDate2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverDate2(nsAString & aAdapterDriverDate)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterVendorID; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterVendorID(nsAString & aAdapterVendorID)
+{
+  aAdapterVendorID = mAdapterVendorID;
+  return NS_OK;
+}
+
+/* readonly attribute DOMString adapterVendorID2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterVendorID2(nsAString & aAdapterVendorID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterDeviceID; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDeviceID(nsAString & aAdapterDeviceID)
+{
+  aAdapterDeviceID = mAdapterDeviceID;
+  return NS_OK;
+}
+
+/* readonly attribute DOMString adapterDeviceID2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterDeviceID2(nsAString & aAdapterDeviceID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterSubsysID; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterSubsysID(nsAString & aAdapterSubsysID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute DOMString adapterSubsysID2; */
+NS_IMETHODIMP
+GfxInfo::GetAdapterSubsysID2(nsAString & aAdapterSubsysID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+/* readonly attribute boolean isGPU2Active; */
+NS_IMETHODIMP
+GfxInfo::GetIsGPU2Active(bool* aIsGPU2Active)
+{
+  return NS_ERROR_FAILURE;
+}
+
+void
+GfxInfo::AddCrashReportAnnotations()
+{
+  /*** STUB ***/
+}
+
+// We don't support checking driver versions on Mac.
+#define IMPLEMENT_MAC_DRIVER_BLOCKLIST(os, vendor, device, features, blockOn, ruleId) \
+  APPEND_TO_DRIVER_BLOCKLIST(os, vendor, device, features, blockOn,           \
+                             DRIVER_COMPARISON_IGNORED, V(0,0,0,0), ruleId, "")
+
+
+const nsTArray<GfxDriverInfo>&
+GfxInfo::GetGfxDriverInfo()
+{
+  if (!mDriverInfo->Length()) {
+    IMPLEMENT_MAC_DRIVER_BLOCKLIST(OperatingSystem::OSX,
+      (nsAString&) GfxDriverInfo::GetDeviceVendor(VendorATI), GfxDriverInfo::allDevices,
+      nsIGfxInfo::FEATURE_WEBGL_MSAA, nsIGfxInfo::FEATURE_BLOCKED_OS_VERSION, "FEATURE_FAILURE_MAC_ATI_NO_MSAA");
+    IMPLEMENT_MAC_DRIVER_BLOCKLIST(OperatingSystem::OSX,
+      (nsAString&) GfxDriverInfo::GetDeviceVendor(VendorATI), (GfxDeviceFamily*) GfxDriverInfo::GetDeviceFamily(RadeonX1000),
+      nsIGfxInfo::FEATURE_OPENGL_LAYERS, nsIGfxInfo::FEATURE_BLOCKED_DEVICE, "FEATURE_FAILURE_MAC_RADEONX1000_NO_TEXTURE2D");
+    IMPLEMENT_MAC_DRIVER_BLOCKLIST(OperatingSystem::OSX,
+      (nsAString&) GfxDriverInfo::GetDeviceVendor(VendorNVIDIA), (GfxDeviceFamily*) GfxDriverInfo::GetDeviceFamily(Geforce7300GT),
+      nsIGfxInfo::FEATURE_WEBGL_OPENGL, nsIGfxInfo::FEATURE_BLOCKED_DEVICE, "FEATURE_FAILURE_MAC_7300_NO_WEBGL");
+  }
+  return *mDriverInfo;
+}
+
+nsresult
+GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
+                              int32_t* aStatus,
+                              nsAString& aSuggestedDriverVersion,
+                              const nsTArray<GfxDriverInfo>& aDriverInfo,
+                              nsACString& aFailureId,
+                              OperatingSystem* aOS /* = nullptr */)
+{
+  NS_ENSURE_ARG_POINTER(aStatus);
+  aSuggestedDriverVersion.SetIsVoid(true);
+  *aStatus = nsIGfxInfo::FEATURE_STATUS_UNKNOWN;
+  OperatingSystem os = OSXVersionToOperatingSystem(mOSXVersion);
+  if (aOS)
+    *aOS = os;
+
+  if (mShutdownOccurred) {
+    return NS_OK;
+  }
+
+  // Don't evaluate special cases when we're evaluating the downloaded blocklist.
+  if (!aDriverInfo.Length()) {
+    if (aFeature == nsIGfxInfo::FEATURE_WEBGL_MSAA) {
+      // Blacklist all ATI cards on OSX, except for
+      // 0x6760 and 0x9488
+      if (mAdapterVendorID.Equals(GfxDriverInfo::GetDeviceVendor(VendorATI), nsCaseInsensitiveStringComparator()) &&
+          (mAdapterDeviceID.LowerCaseEqualsLiteral("0x6760") ||
+           mAdapterDeviceID.LowerCaseEqualsLiteral("0x9488"))) {
+        *aStatus = nsIGfxInfo::FEATURE_STATUS_OK;
+        return NS_OK;
+      }
+    } else if (aFeature == nsIGfxInfo::FEATURE_CANVAS2D_ACCELERATION) {
+      // See bug 1249659
+      switch(os) {
+        case OperatingSystem::OSX10_5:
+        case OperatingSystem::OSX10_6:
+        case OperatingSystem::OSX10_7:
+          *aStatus = nsIGfxInfo::FEATURE_BLOCKED_OS_VERSION;
+          aFailureId = "FEATURE_FAILURE_CANVAS_OSX_VERSION";
+          break;
+        default:
+          *aStatus = nsIGfxInfo::FEATURE_STATUS_OK;
+          break;
+      }
+      return NS_OK;
+    }
+  }
+
+  return GfxInfoBase::GetFeatureStatusImpl(aFeature, aStatus, aSuggestedDriverVersion, aDriverInfo, aFailureId, &os);
+}
+
+nsresult
+GfxInfo::FindMonitors(JSContext* aCx, JS::HandleObject aOutArray)
+{
+  // Getting the refresh rate is a little hard on OS X. We could use
+  // CVDisplayLinkGetNominalOutputVideoRefreshPeriod, but that's a little
+  // involved. Ideally we could query it from vsync. For now, we leave it out.
+  int32_t deviceCount = 0;
+  for (NSScreen* screen in [NSScreen screens]) {
+    NSRect rect = [screen frame];
+
+    JS::Rooted<JSObject*> obj(aCx, JS_NewPlainObject(aCx));
+
+    JS::Rooted<JS::Value> screenWidth(aCx, JS::Int32Value((int)rect.size.width));
+    JS_SetProperty(aCx, obj, "screenWidth", screenWidth);
+
+    JS::Rooted<JS::Value> screenHeight(aCx, JS::Int32Value((int)rect.size.height));
+    JS_SetProperty(aCx, obj, "screenHeight", screenHeight);
+
+    JS::Rooted<JS::Value> scale(aCx, JS::NumberValue(nsCocoaUtils::GetBackingScaleFactor(screen)));
+    JS_SetProperty(aCx, obj, "scale", scale);
+
+    JS::Rooted<JS::Value> element(aCx, JS::ObjectValue(*obj));
+    JS_SetElement(aCx, aOutArray, deviceCount++, element);
+  }
+  return NS_OK;
+}
+
+#ifdef DEBUG
+
+// Implement nsIGfxInfoDebug
+
+/* void spoofVendorID (in DOMString aVendorID); */
+NS_IMETHODIMP GfxInfo::SpoofVendorID(const nsAString & aVendorID)
+{
+  mAdapterVendorID = aVendorID;
+  return NS_OK;
+}
+
+/* void spoofDeviceID (in unsigned long aDeviceID); */
+NS_IMETHODIMP GfxInfo::SpoofDeviceID(const nsAString & aDeviceID)
+{
+  mAdapterDeviceID = aDeviceID;
+  return NS_OK;
+}
+
+/* void spoofDriverVersion (in DOMString aDriverVersion); */
+NS_IMETHODIMP GfxInfo::SpoofDriverVersion(const nsAString & aDriverVersion)
+{
+  mDriverVersion = aDriverVersion;
+  return NS_OK;
+}
+
+/* void spoofOSVersion (in unsigned long aVersion); */
+NS_IMETHODIMP GfxInfo::SpoofOSVersion(uint32_t aVersion)
+{
+  mOSXVersion = aVersion;
+  return NS_OK;
+}
+
+#endif
diff --git a/widget/cocoa/NativeKeyBindings.h b/widget/cocoa/NativeKeyBindings.h
new file mode 100644
index 0000000000..d1ba2c3701
--- /dev/null
+++ b/widget/cocoa/NativeKeyBindings.h
@@ -0,0 +1,48 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_widget_NativeKeyBindings_h_
+#define mozilla_widget_NativeKeyBindings_h_
+
+#import <Cocoa/Cocoa.h>
+#include "mozilla/Attributes.h"
+#include "mozilla/EventForwards.h"
+#include "nsDataHashtable.h"
+#include "nsIWidget.h"
+
+namespace mozilla {
+namespace widget {
+
+typedef nsDataHashtable<nsPtrHashKey<struct objc_selector>, CommandInt>
+  SelectorCommandHashtable;
+
+class NativeKeyBindings final
+{
+  typedef nsIWidget::NativeKeyBindingsType NativeKeyBindingsType;
+  typedef nsIWidget::DoCommandCallback DoCommandCallback;
+
+public:
+  static NativeKeyBindings* GetInstance(NativeKeyBindingsType aType);
+  static void Shutdown();
+
+  void Init(NativeKeyBindingsType aType);
+
+  bool Execute(const WidgetKeyboardEvent& aEvent,
+               DoCommandCallback aCallback,
+               void* aCallbackData);
+
+private:
+  NativeKeyBindings();
+
+  SelectorCommandHashtable mSelectorToCommand;
+
+  static NativeKeyBindings* sInstanceForSingleLineEditor;
+  static NativeKeyBindings* sInstanceForMultiLineEditor;
+}; // NativeKeyBindings
+
+} // namespace widget
+} // namespace mozilla
+
+#endif // mozilla_widget_NativeKeyBindings_h_
diff --git a/widget/cocoa/NativeKeyBindings.mm b/widget/cocoa/NativeKeyBindings.mm
new file mode 100644
index 0000000000..2f4ecadff0
--- /dev/null
+++ b/widget/cocoa/NativeKeyBindings.mm
@@ -0,0 +1,292 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "NativeKeyBindings.h"
+
+#include "nsTArray.h"
+#include "nsCocoaUtils.h"
+#include "mozilla/Logging.h"
+#include "mozilla/TextEvents.h"
+
+namespace mozilla {
+namespace widget {
+
+PRLogModuleInfo* gNativeKeyBindingsLog = nullptr;
+
+NativeKeyBindings* NativeKeyBindings::sInstanceForSingleLineEditor = nullptr;
+NativeKeyBindings* NativeKeyBindings::sInstanceForMultiLineEditor = nullptr;
+
+// static
+NativeKeyBindings*
+NativeKeyBindings::GetInstance(NativeKeyBindingsType aType)
+{
+  switch (aType) {
+    case nsIWidget::NativeKeyBindingsForSingleLineEditor:
+      if (!sInstanceForSingleLineEditor) {
+        sInstanceForSingleLineEditor = new NativeKeyBindings();
+        sInstanceForSingleLineEditor->Init(aType);
+      }
+      return sInstanceForSingleLineEditor;
+    case nsIWidget::NativeKeyBindingsForMultiLineEditor:
+    case nsIWidget::NativeKeyBindingsForRichTextEditor:
+      if (!sInstanceForMultiLineEditor) {
+        sInstanceForMultiLineEditor = new NativeKeyBindings();
+        sInstanceForMultiLineEditor->Init(aType);
+      }
+      return sInstanceForMultiLineEditor;
+    default:
+      MOZ_CRASH("Not implemented");
+      return nullptr;
+  }
+}
+
+// static
+void
+NativeKeyBindings::Shutdown()
+{
+  delete sInstanceForSingleLineEditor;
+  sInstanceForSingleLineEditor = nullptr;
+  delete sInstanceForMultiLineEditor;
+  sInstanceForMultiLineEditor = nullptr;
+}
+
+NativeKeyBindings::NativeKeyBindings()
+{
+}
+
+#define SEL_TO_COMMAND(aSel, aCommand) \
+  mSelectorToCommand.Put( \
+    reinterpret_cast<struct objc_selector *>(@selector(aSel)), aCommand)
+
+void
+NativeKeyBindings::Init(NativeKeyBindingsType aType)
+{
+  if (!gNativeKeyBindingsLog) {
+    gNativeKeyBindingsLog = PR_NewLogModule("NativeKeyBindings");
+  }
+
+  MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+    ("%p NativeKeyBindings::Init", this));
+
+  // Many selectors have a one-to-one mapping to a Gecko command. Those mappings
+  // are registered in mSelectorToCommand.
+
+  // Selectors from NSResponder's "Responding to Action Messages" section and
+  // from NSText's "Action Methods for Editing" section
+
+  // TODO: Improves correctness of left / right meaning
+  // TODO: Add real paragraph motions
+
+  // SEL_TO_COMMAND(cancelOperation:, );
+  // SEL_TO_COMMAND(capitalizeWord:, );
+  // SEL_TO_COMMAND(centerSelectionInVisibleArea:, );
+  // SEL_TO_COMMAND(changeCaseOfLetter:, );
+  // SEL_TO_COMMAND(complete:, );
+  SEL_TO_COMMAND(copy:, CommandCopy);
+  // SEL_TO_COMMAND(copyFont:, );
+  // SEL_TO_COMMAND(copyRuler:, );
+  SEL_TO_COMMAND(cut:, CommandCut);
+  SEL_TO_COMMAND(delete:, CommandDelete);
+  SEL_TO_COMMAND(deleteBackward:, CommandDeleteCharBackward);
+  // SEL_TO_COMMAND(deleteBackwardByDecomposingPreviousCharacter:, );
+  SEL_TO_COMMAND(deleteForward:, CommandDeleteCharForward);
+
+  // TODO: deleteTo* selectors are also supposed to add text to a kill buffer
+  SEL_TO_COMMAND(deleteToBeginningOfLine:, CommandDeleteToBeginningOfLine);
+  SEL_TO_COMMAND(deleteToBeginningOfParagraph:, CommandDeleteToBeginningOfLine);
+  SEL_TO_COMMAND(deleteToEndOfLine:, CommandDeleteToEndOfLine);
+  SEL_TO_COMMAND(deleteToEndOfParagraph:, CommandDeleteToEndOfLine);
+  // SEL_TO_COMMAND(deleteToMark:, );
+
+  SEL_TO_COMMAND(deleteWordBackward:, CommandDeleteWordBackward);
+  SEL_TO_COMMAND(deleteWordForward:, CommandDeleteWordForward);
+  // SEL_TO_COMMAND(indent:, );
+  // SEL_TO_COMMAND(insertBacktab:, );
+  // SEL_TO_COMMAND(insertContainerBreak:, );
+  // SEL_TO_COMMAND(insertLineBreak:, );
+  // SEL_TO_COMMAND(insertNewline:, );
+  // SEL_TO_COMMAND(insertNewlineIgnoringFieldEditor:, );
+  // SEL_TO_COMMAND(insertParagraphSeparator:, );
+  // SEL_TO_COMMAND(insertTab:, );
+  // SEL_TO_COMMAND(insertTabIgnoringFieldEditor:, );
+  // SEL_TO_COMMAND(insertDoubleQuoteIgnoringSubstitution:, );
+  // SEL_TO_COMMAND(insertSingleQuoteIgnoringSubstitution:, );
+  // SEL_TO_COMMAND(lowercaseWord:, );
+  SEL_TO_COMMAND(moveBackward:, CommandCharPrevious);
+  SEL_TO_COMMAND(moveBackwardAndModifySelection:, CommandSelectCharPrevious);
+  if (aType == nsIWidget::NativeKeyBindingsForSingleLineEditor) {
+    SEL_TO_COMMAND(moveDown:, CommandEndLine);
+  } else {
+    SEL_TO_COMMAND(moveDown:, CommandLineNext);
+  }
+  SEL_TO_COMMAND(moveDownAndModifySelection:, CommandSelectLineNext);
+  SEL_TO_COMMAND(moveForward:, CommandCharNext);
+  SEL_TO_COMMAND(moveForwardAndModifySelection:, CommandSelectCharNext);
+  SEL_TO_COMMAND(moveLeft:, CommandCharPrevious);
+  SEL_TO_COMMAND(moveLeftAndModifySelection:, CommandSelectCharPrevious);
+  SEL_TO_COMMAND(moveParagraphBackwardAndModifySelection:,
+    CommandSelectBeginLine);
+  SEL_TO_COMMAND(moveParagraphForwardAndModifySelection:, CommandSelectEndLine);
+  SEL_TO_COMMAND(moveRight:, CommandCharNext);
+  SEL_TO_COMMAND(moveRightAndModifySelection:, CommandSelectCharNext);
+  SEL_TO_COMMAND(moveToBeginningOfDocument:, CommandMoveTop);
+  SEL_TO_COMMAND(moveToBeginningOfDocumentAndModifySelection:,
+    CommandSelectTop);
+  SEL_TO_COMMAND(moveToBeginningOfLine:, CommandBeginLine);
+  SEL_TO_COMMAND(moveToBeginningOfLineAndModifySelection:,
+    CommandSelectBeginLine);
+  SEL_TO_COMMAND(moveToBeginningOfParagraph:, CommandBeginLine);
+  SEL_TO_COMMAND(moveToBeginningOfParagraphAndModifySelection:,
+    CommandSelectBeginLine);
+  SEL_TO_COMMAND(moveToEndOfDocument:, CommandMoveBottom);
+  SEL_TO_COMMAND(moveToEndOfDocumentAndModifySelection:, CommandSelectBottom);
+  SEL_TO_COMMAND(moveToEndOfLine:, CommandEndLine);
+  SEL_TO_COMMAND(moveToEndOfLineAndModifySelection:, CommandSelectEndLine);
+  SEL_TO_COMMAND(moveToEndOfParagraph:, CommandEndLine);
+  SEL_TO_COMMAND(moveToEndOfParagraphAndModifySelection:, CommandSelectEndLine);
+  SEL_TO_COMMAND(moveToLeftEndOfLine:, CommandBeginLine);
+  SEL_TO_COMMAND(moveToLeftEndOfLineAndModifySelection:,
+    CommandSelectBeginLine);
+  SEL_TO_COMMAND(moveToRightEndOfLine:, CommandEndLine);
+  SEL_TO_COMMAND(moveToRightEndOfLineAndModifySelection:, CommandSelectEndLine);
+  if (aType == nsIWidget::NativeKeyBindingsForSingleLineEditor) {
+    SEL_TO_COMMAND(moveUp:, CommandBeginLine);
+  } else {
+    SEL_TO_COMMAND(moveUp:, CommandLinePrevious);
+  }
+  SEL_TO_COMMAND(moveUpAndModifySelection:, CommandSelectLinePrevious);
+  SEL_TO_COMMAND(moveWordBackward:, CommandWordPrevious);
+  SEL_TO_COMMAND(moveWordBackwardAndModifySelection:,
+    CommandSelectWordPrevious);
+  SEL_TO_COMMAND(moveWordForward:, CommandWordNext);
+  SEL_TO_COMMAND(moveWordForwardAndModifySelection:, CommandSelectWordNext);
+  SEL_TO_COMMAND(moveWordLeft:, CommandWordPrevious);
+  SEL_TO_COMMAND(moveWordLeftAndModifySelection:, CommandSelectWordPrevious);
+  SEL_TO_COMMAND(moveWordRight:, CommandWordNext);
+  SEL_TO_COMMAND(moveWordRightAndModifySelection:, CommandSelectWordNext);
+  SEL_TO_COMMAND(pageDown:, CommandMovePageDown);
+  SEL_TO_COMMAND(pageDownAndModifySelection:, CommandSelectPageDown);
+  SEL_TO_COMMAND(pageUp:, CommandMovePageUp);
+  SEL_TO_COMMAND(pageUpAndModifySelection:, CommandSelectPageUp);
+  SEL_TO_COMMAND(paste:, CommandPaste);
+  // SEL_TO_COMMAND(pasteFont:, );
+  // SEL_TO_COMMAND(pasteRuler:, );
+  SEL_TO_COMMAND(scrollLineDown:, CommandScrollLineDown);
+  SEL_TO_COMMAND(scrollLineUp:, CommandScrollLineUp);
+  SEL_TO_COMMAND(scrollPageDown:, CommandScrollPageDown);
+  SEL_TO_COMMAND(scrollPageUp:, CommandScrollPageUp);
+  SEL_TO_COMMAND(scrollToBeginningOfDocument:, CommandScrollTop);
+  SEL_TO_COMMAND(scrollToEndOfDocument:, CommandScrollBottom);
+  SEL_TO_COMMAND(selectAll:, CommandSelectAll);
+  // selectLine: is complex, see KeyDown
+  if (aType == nsIWidget::NativeKeyBindingsForSingleLineEditor) {
+    SEL_TO_COMMAND(selectParagraph:, CommandSelectAll);
+  }
+  // SEL_TO_COMMAND(selectToMark:, );
+  // selectWord: is complex, see KeyDown
+  // SEL_TO_COMMAND(setMark:, );
+  // SEL_TO_COMMAND(showContextHelp:, );
+  // SEL_TO_COMMAND(supplementalTargetForAction:sender:, );
+  // SEL_TO_COMMAND(swapWithMark:, );
+  // SEL_TO_COMMAND(transpose:, );
+  // SEL_TO_COMMAND(transposeWords:, );
+  // SEL_TO_COMMAND(uppercaseWord:, );
+  // SEL_TO_COMMAND(yank:, );
+}
+
+#undef SEL_TO_COMMAND
+
+bool
+NativeKeyBindings::Execute(const WidgetKeyboardEvent& aEvent,
+                           DoCommandCallback aCallback,
+                           void* aCallbackData)
+{
+  MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+    ("%p NativeKeyBindings::KeyPress", this));
+
+  // Recover the current event, which should always be the key down we are
+  // responding to.
+
+  NSEvent* cocoaEvent = reinterpret_cast<NSEvent*>(aEvent.mNativeKeyEvent);
+
+  if (!cocoaEvent || [cocoaEvent type] != NSKeyDown) {
+    MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+      ("%p NativeKeyBindings::KeyPress, no Cocoa key down event", this));
+
+    return false;
+  }
+
+  MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+    ("%p NativeKeyBindings::KeyPress, interpreting", this));
+
+  AutoTArray<KeyBindingsCommand, 2> bindingCommands;
+  nsCocoaUtils::GetCommandsFromKeyEvent(cocoaEvent, bindingCommands);
+
+  MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+    ("%p NativeKeyBindings::KeyPress, bindingCommands=%u",
+     this, bindingCommands.Length()));
+
+  AutoTArray<Command, 4> geckoCommands;
+
+  for (uint32_t i = 0; i < bindingCommands.Length(); i++) {
+    SEL selector = bindingCommands[i].selector;
+
+    if (MOZ_LOG_TEST(gNativeKeyBindingsLog, LogLevel::Info)) {
+      NSString* selectorString = NSStringFromSelector(selector);
+      nsAutoString nsSelectorString;
+      nsCocoaUtils::GetStringForNSString(selectorString, nsSelectorString);
+
+      MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+        ("%p NativeKeyBindings::KeyPress, selector=%s",
+         this, NS_LossyConvertUTF16toASCII(nsSelectorString).get()));
+    }
+
+    // Try to find a simple mapping in the hashtable
+    Command geckoCommand = static_cast<Command>(mSelectorToCommand.Get(
+      reinterpret_cast<struct objc_selector*>(selector)));
+
+    if (geckoCommand) {
+      geckoCommands.AppendElement(geckoCommand);
+    } else if (selector == @selector(selectLine:)) {
+      // This is functional, but Cocoa's version is direction-less in that
+      // selection direction is not determined until some future directed action
+      // is taken. See bug 282097, comment 79 for more details.
+      geckoCommands.AppendElement(CommandBeginLine);
+      geckoCommands.AppendElement(CommandSelectEndLine);
+    } else if (selector == @selector(selectWord:)) {
+      // This is functional, but Cocoa's version is direction-less in that
+      // selection direction is not determined until some future directed action
+      // is taken. See bug 282097, comment 79 for more details.
+      geckoCommands.AppendElement(CommandWordPrevious);
+      geckoCommands.AppendElement(CommandSelectWordNext);
+    }
+  }
+
+  if (geckoCommands.IsEmpty()) {
+    MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+      ("%p NativeKeyBindings::KeyPress, handled=false", this));
+
+    return false;
+  }
+
+  for (uint32_t i = 0; i < geckoCommands.Length(); i++) {
+    Command geckoCommand = geckoCommands[i];
+
+    MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+      ("%p NativeKeyBindings::KeyPress, command=%s",
+       this, WidgetKeyboardEvent::GetCommandStr(geckoCommand)));
+
+    // Execute the Gecko command
+    aCallback(geckoCommand, aCallbackData);
+  }
+
+  MOZ_LOG(gNativeKeyBindingsLog, LogLevel::Info,
+    ("%p NativeKeyBindings::KeyPress, handled=true", this));
+
+  return true;
+}
+
+} // namespace widget
+} // namespace mozilla
diff --git a/widget/cocoa/OSXNotificationCenter.h b/widget/cocoa/OSXNotificationCenter.h
new file mode 100644
index 0000000000..30767b5c55
--- /dev/null
+++ b/widget/cocoa/OSXNotificationCenter.h
@@ -0,0 +1,55 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef OSXNotificationCenter_h
+#define OSXNotificationCenter_h
+
+#import <Foundation/Foundation.h>
+#include "nsIAlertsService.h"
+#include "imgINotificationObserver.h"
+#include "nsITimer.h"
+#include "nsTArray.h"
+#include "mozilla/RefPtr.h"
+
+@class mozNotificationCenterDelegate;
+
+#if !defined(MAC_OS_X_VERSION_10_8) || (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_8)
+typedef NSInteger NSUserNotificationActivationType;
+#endif
+
+namespace mozilla {
+
+class OSXNotificationInfo;
+
+class OSXNotificationCenter : public nsIAlertsService,
+                              public nsIAlertsIconData,
+                              public nsIAlertNotificationImageListener
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIALERTSSERVICE
+  NS_DECL_NSIALERTSICONDATA
+  NS_DECL_NSIALERTNOTIFICATIONIMAGELISTENER
+
+  OSXNotificationCenter();
+
+  nsresult Init();
+  void CloseAlertCocoaString(NSString *aAlertName);
+  void OnActivate(NSString *aAlertName, NSUserNotificationActivationType aActivationType,
+                  unsigned long long aAdditionalActionIndex);
+  void ShowPendingNotification(OSXNotificationInfo *osxni);
+
+protected:
+  virtual ~OSXNotificationCenter();
+
+private:
+  mozNotificationCenterDelegate *mDelegate;
+  nsTArray<RefPtr<OSXNotificationInfo> > mActiveAlerts;
+  nsTArray<RefPtr<OSXNotificationInfo> > mPendingAlerts;
+};
+
+} // namespace mozilla
+
+#endif // OSXNotificationCenter_h
diff --git a/widget/cocoa/OSXNotificationCenter.mm b/widget/cocoa/OSXNotificationCenter.mm
new file mode 100644
index 0000000000..e9e36a96be
--- /dev/null
+++ b/widget/cocoa/OSXNotificationCenter.mm
@@ -0,0 +1,589 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "OSXNotificationCenter.h"
+#import <AppKit/AppKit.h>
+#include "imgIRequest.h"
+#include "imgIContainer.h"
+#include "nsICancelable.h"
+#include "nsIStringBundle.h"
+#include "nsNetUtil.h"
+#import "nsCocoaUtils.h"
+#include "nsComponentManagerUtils.h"
+#include "nsContentUtils.h"
+#include "nsObjCExceptions.h"
+#include "nsString.h"
+#include "nsCOMPtr.h"
+#include "nsIObserver.h"
+
+using namespace mozilla;
+
+#define MAX_NOTIFICATION_NAME_LEN 5000
+
+#if !defined(MAC_OS_X_VERSION_10_8) || (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_8)
+@protocol NSUserNotificationCenterDelegate
+@end
+static NSString * const NSUserNotificationDefaultSoundName = @"DefaultSoundName";
+enum {
+  NSUserNotificationActivationTypeNone = 0,
+  NSUserNotificationActivationTypeContentsClicked = 1,
+  NSUserNotificationActivationTypeActionButtonClicked = 2,
+};
+#endif
+
+#if !defined(MAC_OS_X_VERSION_10_9) || (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_9)
+enum {
+  NSUserNotificationActivationTypeReplied = 3,
+};
+#endif
+
+#if !defined(MAC_OS_X_VERSION_10_10) || (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_10)
+enum {
+  NSUserNotificationActivationTypeAdditionalActionClicked = 4
+};
+#endif
+
+@protocol FakeNSUserNotification <NSObject>
+@property (copy) NSString* title;
+@property (copy) NSString* subtitle;
+@property (copy) NSString* informativeText;
+@property (copy) NSString* actionButtonTitle;
+@property (copy) NSDictionary* userInfo;
+@property (copy) NSDate* deliveryDate;
+@property (copy) NSTimeZone* deliveryTimeZone;
+@property (copy) NSDateComponents* deliveryRepeatInterval;
+@property (readonly) NSDate* actualDeliveryDate;
+@property (readonly, getter=isPresented) BOOL presented;
+@property (readonly, getter=isRemote) BOOL remote;
+@property (copy) NSString* soundName;
+@property BOOL hasActionButton;
+@property (readonly) NSUserNotificationActivationType activationType;
+@property (copy) NSString *otherButtonTitle;
+@property (copy) NSImage *contentImage;
+@end
+
+@protocol FakeNSUserNotificationCenter <NSObject>
++ (id<FakeNSUserNotificationCenter>)defaultUserNotificationCenter;
+@property (assign) id <NSUserNotificationCenterDelegate> delegate;
+@property (copy) NSArray *scheduledNotifications;
+- (void)scheduleNotification:(id<FakeNSUserNotification>)notification;
+- (void)removeScheduledNotification:(id<FakeNSUserNotification>)notification;
+@property (readonly) NSArray *deliveredNotifications;
+- (void)deliverNotification:(id<FakeNSUserNotification>)notification;
+- (void)removeDeliveredNotification:(id<FakeNSUserNotification>)notification;
+- (void)removeAllDeliveredNotifications;
+- (void)_removeAllDisplayedNotifications;
+- (void)_removeDisplayedNotification:(id<FakeNSUserNotification>)notification;
+@end
+
+@interface mozNotificationCenterDelegate : NSObject <NSUserNotificationCenterDelegate>
+{
+  OSXNotificationCenter *mOSXNC;
+}
+  - (id)initWithOSXNC:(OSXNotificationCenter*)osxnc;
+@end
+
+@implementation mozNotificationCenterDelegate
+
+- (id)initWithOSXNC:(OSXNotificationCenter*)osxnc
+{
+  [super init];
+  // We should *never* outlive this OSXNotificationCenter.
+  mOSXNC = osxnc;
+  return self;
+}
+
+- (void)userNotificationCenter:(id<FakeNSUserNotificationCenter>)center
+        didDeliverNotification:(id<FakeNSUserNotification>)notification
+{
+
+}
+
+- (void)userNotificationCenter:(id<FakeNSUserNotificationCenter>)center
+       didActivateNotification:(id<FakeNSUserNotification>)notification
+{
+  unsigned long long additionalActionIndex = ULLONG_MAX;
+  if ([notification respondsToSelector:@selector(_alternateActionIndex)]) {
+    NSNumber *alternateActionIndex = [(NSObject*)notification valueForKey:@"_alternateActionIndex"];
+    additionalActionIndex = [alternateActionIndex unsignedLongLongValue];
+  }
+  mOSXNC->OnActivate([[notification userInfo] valueForKey:@"name"],
+                     notification.activationType,
+                     additionalActionIndex);
+}
+
+- (BOOL)userNotificationCenter:(id<FakeNSUserNotificationCenter>)center
+     shouldPresentNotification:(id<FakeNSUserNotification>)notification
+{
+  return YES;
+}
+
+// This is an undocumented method that we need for parity with Safari.
+// Apple bug #15440664.
+- (void)userNotificationCenter:(id<FakeNSUserNotificationCenter>)center
+  didRemoveDeliveredNotifications:(NSArray *)notifications
+{
+  for (id<FakeNSUserNotification> notification in notifications) {
+    NSString *name = [[notification userInfo] valueForKey:@"name"];
+    mOSXNC->CloseAlertCocoaString(name);
+  }
+}
+
+// This is an undocumented method that we need to be notified if a user clicks the close button.
+- (void)userNotificationCenter:(id<FakeNSUserNotificationCenter>)center
+  didDismissAlert:(id<FakeNSUserNotification>)notification
+{
+  NSString *name = [[notification userInfo] valueForKey:@"name"];
+  mOSXNC->CloseAlertCocoaString(name);
+}
+
+@end
+
+namespace mozilla {
+
+enum {
+  OSXNotificationActionDisable = 0,
+  OSXNotificationActionSettings = 1,
+};
+
+class OSXNotificationInfo final : public nsISupports {
+private:
+  virtual ~OSXNotificationInfo();
+
+public:
+  NS_DECL_ISUPPORTS
+  OSXNotificationInfo(NSString *name, nsIObserver *observer,
+                      const nsAString & alertCookie);
+
+  NSString *mName;
+  nsCOMPtr<nsIObserver> mObserver;
+  nsString mCookie;
+  RefPtr<nsICancelable> mIconRequest;
+  id<FakeNSUserNotification> mPendingNotifiction;
+};
+
+NS_IMPL_ISUPPORTS0(OSXNotificationInfo)
+
+OSXNotificationInfo::OSXNotificationInfo(NSString *name, nsIObserver *observer,
+                                         const nsAString & alertCookie)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_ASSERTION(name, "Cannot create OSXNotificationInfo without a name!");
+  mName = [name retain];
+  mObserver = observer;
+  mCookie = alertCookie;
+  mPendingNotifiction = nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+OSXNotificationInfo::~OSXNotificationInfo()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mName release];
+  [mPendingNotifiction release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static id<FakeNSUserNotificationCenter> GetNotificationCenter() {
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  Class c = NSClassFromString(@"NSUserNotificationCenter");
+  return [c performSelector:@selector(defaultUserNotificationCenter)];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+OSXNotificationCenter::OSXNotificationCenter()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  mDelegate = [[mozNotificationCenterDelegate alloc] initWithOSXNC:this];
+  GetNotificationCenter().delegate = mDelegate;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+OSXNotificationCenter::~OSXNotificationCenter()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [GetNotificationCenter() removeAllDeliveredNotifications];
+  [mDelegate release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMPL_ISUPPORTS(OSXNotificationCenter, nsIAlertsService, nsIAlertsIconData,
+                  nsIAlertNotificationImageListener)
+
+nsresult OSXNotificationCenter::Init()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  return (!!NSClassFromString(@"NSUserNotification")) ? NS_OK : NS_ERROR_FAILURE;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+OSXNotificationCenter::ShowAlertNotification(const nsAString & aImageUrl, const nsAString & aAlertTitle,
+                                             const nsAString & aAlertText, bool aAlertTextClickable,
+                                             const nsAString & aAlertCookie,
+                                             nsIObserver * aAlertListener,
+                                             const nsAString & aAlertName,
+                                             const nsAString & aBidi,
+                                             const nsAString & aLang,
+                                             const nsAString & aData,
+                                             nsIPrincipal * aPrincipal,
+                                             bool aInPrivateBrowsing,
+                                             bool aRequireInteraction)
+{
+  nsCOMPtr<nsIAlertNotification> alert =
+    do_CreateInstance(ALERT_NOTIFICATION_CONTRACTID);
+  NS_ENSURE_TRUE(alert, NS_ERROR_FAILURE);
+  nsresult rv = alert->Init(aAlertName, aImageUrl, aAlertTitle,
+                            aAlertText, aAlertTextClickable,
+                            aAlertCookie, aBidi, aLang, aData,
+                            aPrincipal, aInPrivateBrowsing,
+                            aRequireInteraction);
+  NS_ENSURE_SUCCESS(rv, rv);
+  return ShowAlert(alert, aAlertListener);
+}
+
+NS_IMETHODIMP
+OSXNotificationCenter::ShowPersistentNotification(const nsAString& aPersistentData,
+                                                  nsIAlertNotification* aAlert,
+                                                  nsIObserver* aAlertListener)
+{
+  return ShowAlert(aAlert, aAlertListener);
+}
+
+NS_IMETHODIMP
+OSXNotificationCenter::ShowAlert(nsIAlertNotification* aAlert,
+                                 nsIObserver* aAlertListener)
+{
+  return ShowAlertWithIconData(aAlert, aAlertListener, 0, nullptr);
+}
+
+NS_IMETHODIMP
+OSXNotificationCenter::ShowAlertWithIconData(nsIAlertNotification* aAlert,
+                                             nsIObserver* aAlertListener,
+                                             uint32_t aIconSize,
+                                             const uint8_t* aIconData)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NS_ENSURE_ARG(aAlert);
+
+  Class unClass = NSClassFromString(@"NSUserNotification");
+  id<FakeNSUserNotification> notification = [[unClass alloc] init];
+
+  nsAutoString title;
+  nsresult rv = aAlert->GetTitle(title);
+  NS_ENSURE_SUCCESS(rv, rv);
+  notification.title = nsCocoaUtils::ToNSString(title);
+
+  nsAutoString hostPort;
+  rv = aAlert->GetSource(hostPort);
+  NS_ENSURE_SUCCESS(rv, rv);
+  nsCOMPtr<nsIStringBundle> bundle;
+  nsCOMPtr<nsIStringBundleService> sbs = do_GetService(NS_STRINGBUNDLE_CONTRACTID);
+  sbs->CreateBundle("chrome://alerts/locale/alert.properties", getter_AddRefs(bundle));
+
+  if (!hostPort.IsEmpty() && bundle) {
+    const char16_t* formatStrings[] = { hostPort.get() };
+    nsXPIDLString notificationSource;
+    bundle->FormatStringFromName(u"source.label",
+                                 formatStrings,
+                                 ArrayLength(formatStrings),
+                                 getter_Copies(notificationSource));
+    notification.subtitle = nsCocoaUtils::ToNSString(notificationSource);
+  }
+
+  nsAutoString text;
+  rv = aAlert->GetText(text);
+  NS_ENSURE_SUCCESS(rv, rv);
+  notification.informativeText = nsCocoaUtils::ToNSString(text);
+
+  notification.soundName = NSUserNotificationDefaultSoundName;
+  notification.hasActionButton = NO;
+
+  // If this is not an application/extension alert, show additional actions dealing with permissions.
+  bool isActionable;
+  if (bundle && NS_SUCCEEDED(aAlert->GetActionable(&isActionable)) && isActionable) {
+    nsXPIDLString closeButtonTitle, actionButtonTitle, disableButtonTitle, settingsButtonTitle;
+    bundle->GetStringFromName(u"closeButton.title",
+                              getter_Copies(closeButtonTitle));
+    bundle->GetStringFromName(u"actionButton.label",
+                              getter_Copies(actionButtonTitle));
+    if (!hostPort.IsEmpty()) {
+      const char16_t* formatStrings[] = { hostPort.get() };
+      bundle->FormatStringFromName(u"webActions.disableForOrigin.label",
+                                   formatStrings,
+                                   ArrayLength(formatStrings),
+                                   getter_Copies(disableButtonTitle));
+    }
+    bundle->GetStringFromName(u"webActions.settings.label",
+                              getter_Copies(settingsButtonTitle));
+
+    notification.otherButtonTitle = nsCocoaUtils::ToNSString(closeButtonTitle);
+
+    // OS X 10.8 only shows action buttons if the "Alerts" style is set in
+    // Notification Center preferences, and doesn't support the alternate
+    // action menu.
+    if ([notification respondsToSelector:@selector(set_showsButtons:)] &&
+        [notification respondsToSelector:@selector(set_alwaysShowAlternateActionMenu:)] &&
+        [notification respondsToSelector:@selector(set_alternateActionButtonTitles:)]) {
+
+      notification.hasActionButton = YES;
+      notification.actionButtonTitle = nsCocoaUtils::ToNSString(actionButtonTitle);
+
+      [(NSObject*)notification setValue:@(YES) forKey:@"_showsButtons"];
+      [(NSObject*)notification setValue:@(YES) forKey:@"_alwaysShowAlternateActionMenu"];
+      [(NSObject*)notification setValue:@[
+                                          nsCocoaUtils::ToNSString(disableButtonTitle),
+                                          nsCocoaUtils::ToNSString(settingsButtonTitle)
+                                          ]
+                               forKey:@"_alternateActionButtonTitles"];
+    }
+  }
+  nsAutoString name;
+  rv = aAlert->GetName(name);
+  // Don't let an alert name be more than MAX_NOTIFICATION_NAME_LEN characters.
+  // More than that shouldn't be necessary and userInfo (assigned to below) has
+  // a length limit of 16k on OS X 10.11. Exception thrown if limit exceeded.
+  if (name.Length() > MAX_NOTIFICATION_NAME_LEN) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NS_ENSURE_SUCCESS(rv, rv);
+  NSString *alertName = nsCocoaUtils::ToNSString(name);
+  if (!alertName) {
+    return NS_ERROR_FAILURE;
+  }
+  notification.userInfo = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:alertName, nil]
+                                                      forKeys:[NSArray arrayWithObjects:@"name", nil]];
+
+  nsAutoString cookie;
+  rv = aAlert->GetCookie(cookie);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  OSXNotificationInfo *osxni = new OSXNotificationInfo(alertName, aAlertListener, cookie);
+
+  // Show the favicon if supported on this version of OS X.
+  if (aIconSize > 0 &&
+      [notification respondsToSelector:@selector(set_identityImage:)] &&
+      [notification respondsToSelector:@selector(set_identityImageHasBorder:)]) {
+
+    NSData *iconData = [NSData dataWithBytes:aIconData length:aIconSize];
+    NSImage *icon = [[[NSImage alloc] initWithData:iconData] autorelease];
+
+    [(NSObject*)notification setValue:icon forKey:@"_identityImage"];
+    [(NSObject*)notification setValue:@(NO) forKey:@"_identityImageHasBorder"];
+  }
+
+  bool inPrivateBrowsing;
+  rv = aAlert->GetInPrivateBrowsing(&inPrivateBrowsing);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Show the notification without waiting for an image if there is no icon URL or
+  // notification icons are not supported on this version of OS X.
+  if (![unClass instancesRespondToSelector:@selector(setContentImage:)]) {
+    CloseAlertCocoaString(alertName);
+    mActiveAlerts.AppendElement(osxni);
+    [GetNotificationCenter() deliverNotification:notification];
+    [notification release];
+    if (aAlertListener) {
+      aAlertListener->Observe(nullptr, "alertshow", cookie.get());
+    }
+  } else {
+    mPendingAlerts.AppendElement(osxni);
+    osxni->mPendingNotifiction = notification;
+    // Wait six seconds for the image to load.
+    rv = aAlert->LoadImage(6000, this, osxni,
+                           getter_AddRefs(osxni->mIconRequest));
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      ShowPendingNotification(osxni);
+    }
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+OSXNotificationCenter::CloseAlert(const nsAString& aAlertName,
+                                  nsIPrincipal* aPrincipal)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSString *alertName = nsCocoaUtils::ToNSString(aAlertName);
+  CloseAlertCocoaString(alertName);
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void
+OSXNotificationCenter::CloseAlertCocoaString(NSString *aAlertName)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!aAlertName) {
+    return; // Can't do anything without a name
+  }
+
+  NSArray *notifications = [GetNotificationCenter() deliveredNotifications];
+  for (id<FakeNSUserNotification> notification in notifications) {
+    NSString *name = [[notification userInfo] valueForKey:@"name"];
+    if ([name isEqualToString:aAlertName]) {
+      [GetNotificationCenter() removeDeliveredNotification:notification];
+      [GetNotificationCenter() _removeDisplayedNotification:notification];
+      break;
+    }
+  }
+
+  for (unsigned int i = 0; i < mActiveAlerts.Length(); i++) {
+    OSXNotificationInfo *osxni = mActiveAlerts[i];
+    if ([aAlertName isEqualToString:osxni->mName]) {
+      if (osxni->mObserver) {
+        osxni->mObserver->Observe(nullptr, "alertfinished", osxni->mCookie.get());
+      }
+      if (osxni->mIconRequest) {
+        osxni->mIconRequest->Cancel(NS_BINDING_ABORTED);
+        osxni->mIconRequest = nullptr;
+      }
+      mActiveAlerts.RemoveElementAt(i);
+      break;
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+OSXNotificationCenter::OnActivate(NSString *aAlertName,
+                                  NSUserNotificationActivationType aActivationType,
+                                  unsigned long long aAdditionalActionIndex)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!aAlertName) {
+    return; // Can't do anything without a name
+  }
+
+  for (unsigned int i = 0; i < mActiveAlerts.Length(); i++) {
+    OSXNotificationInfo *osxni = mActiveAlerts[i];
+    if ([aAlertName isEqualToString:osxni->mName]) {
+      if (osxni->mObserver) {
+        switch ((int)aActivationType) {
+          case NSUserNotificationActivationTypeAdditionalActionClicked:
+          case NSUserNotificationActivationTypeActionButtonClicked:
+            switch (aAdditionalActionIndex) {
+              case OSXNotificationActionDisable:
+                osxni->mObserver->Observe(nullptr, "alertdisablecallback", osxni->mCookie.get());
+                break;
+              case OSXNotificationActionSettings:
+                osxni->mObserver->Observe(nullptr, "alertsettingscallback", osxni->mCookie.get());
+                break;
+              default:
+                NS_WARNING("Unknown NSUserNotification additional action clicked");
+                break;
+            }
+            break;
+          default:
+            osxni->mObserver->Observe(nullptr, "alertclickcallback", osxni->mCookie.get());
+            break;
+        }
+      }
+      return;
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+OSXNotificationCenter::ShowPendingNotification(OSXNotificationInfo *osxni)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (osxni->mIconRequest) {
+    osxni->mIconRequest->Cancel(NS_BINDING_ABORTED);
+    osxni->mIconRequest = nullptr;
+  }
+
+  CloseAlertCocoaString(osxni->mName);
+
+  for (unsigned int i = 0; i < mPendingAlerts.Length(); i++) {
+    if (mPendingAlerts[i] == osxni) {
+      mActiveAlerts.AppendElement(osxni);
+      mPendingAlerts.RemoveElementAt(i);
+      break;
+    }
+  }
+
+  [GetNotificationCenter() deliverNotification:osxni->mPendingNotifiction];
+
+  if (osxni->mObserver) {
+    osxni->mObserver->Observe(nullptr, "alertshow", osxni->mCookie.get());
+  }
+
+  [osxni->mPendingNotifiction release];
+  osxni->mPendingNotifiction = nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP
+OSXNotificationCenter::OnImageMissing(nsISupports* aUserData)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  OSXNotificationInfo *osxni = static_cast<OSXNotificationInfo*>(aUserData);
+  if (osxni->mPendingNotifiction) {
+    // If there was an error getting the image, or the request timed out, show
+    // the notification without a content image.
+    ShowPendingNotification(osxni);
+  }
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+OSXNotificationCenter::OnImageReady(nsISupports* aUserData,
+                                    imgIRequest* aRequest)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  nsCOMPtr<imgIContainer> image;
+  nsresult rv = aRequest->GetImage(getter_AddRefs(image));
+  if (NS_WARN_IF(NS_FAILED(rv) || !image)) {
+    return rv;
+  }
+
+  OSXNotificationInfo *osxni = static_cast<OSXNotificationInfo*>(aUserData);
+  if (!osxni->mPendingNotifiction) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NSImage *cocoaImage = nil;
+  nsCocoaUtils::CreateNSImageFromImageContainer(image, imgIContainer::FRAME_FIRST, &cocoaImage, 1.0f);
+  (osxni->mPendingNotifiction).contentImage = cocoaImage;
+  [cocoaImage release];
+  ShowPendingNotification(osxni);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+} // namespace mozilla
diff --git a/widget/cocoa/RectTextureImage.h b/widget/cocoa/RectTextureImage.h
new file mode 100644
index 0000000000..022b216c6b
--- /dev/null
+++ b/widget/cocoa/RectTextureImage.h
@@ -0,0 +1,80 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef RectTextureImage_h_
+#define RectTextureImage_h_
+
+#include "mozilla/RefPtr.h"
+
+class MacIOSurface;
+
+namespace mozilla {
+
+namespace gl {
+class GLContext;
+} // namespace gl
+
+namespace widget {
+
+// Manages a texture which can resize dynamically, binds to the
+// LOCAL_GL_TEXTURE_RECTANGLE_ARB texture target and is automatically backed
+// by a power-of-two size GL texture. The latter two features are used for
+// compatibility with older Mac hardware which we block GL layers on.
+// RectTextureImages are used both for accelerated GL layers drawing and for
+// OMTC BasicLayers drawing.
+class RectTextureImage {
+public:
+  RectTextureImage();
+
+  virtual ~RectTextureImage();
+
+  already_AddRefed<gfx::DrawTarget>
+    BeginUpdate(const LayoutDeviceIntSize& aNewSize,
+                const LayoutDeviceIntRegion& aDirtyRegion =
+                  LayoutDeviceIntRegion());
+  void EndUpdate();
+
+  void UpdateIfNeeded(const LayoutDeviceIntSize& aNewSize,
+                      const LayoutDeviceIntRegion& aDirtyRegion,
+                      void (^aCallback)(gfx::DrawTarget*,
+                                        const LayoutDeviceIntRegion&))
+  {
+    RefPtr<gfx::DrawTarget> drawTarget = BeginUpdate(aNewSize, aDirtyRegion);
+    if (drawTarget) {
+      aCallback(drawTarget, GetUpdateRegion());
+      EndUpdate();
+    }
+  }
+
+  void UpdateFromCGContext(const LayoutDeviceIntSize& aNewSize,
+                           const LayoutDeviceIntRegion& aDirtyRegion,
+                           CGContextRef aCGContext);
+
+  LayoutDeviceIntRegion GetUpdateRegion() {
+    MOZ_ASSERT(mInUpdate, "update region only valid during update");
+    return mUpdateRegion;
+  }
+
+  void Draw(mozilla::layers::GLManager* aManager,
+            const LayoutDeviceIntPoint& aLocation,
+            const gfx::Matrix4x4& aTransform = gfx::Matrix4x4());
+
+
+protected:
+  void DeleteTexture();
+  void BindIOSurfaceToTexture(gl::GLContext* aGL);
+
+  RefPtr<MacIOSurface> mIOSurface;
+  gl::GLContext* mGLContext;
+  LayoutDeviceIntRegion mUpdateRegion;
+  LayoutDeviceIntSize mBufferSize;
+  GLuint mTexture;
+  bool mInUpdate;
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif // RectTextureImage_h_
diff --git a/widget/cocoa/RectTextureImage.mm b/widget/cocoa/RectTextureImage.mm
new file mode 100644
index 0000000000..c67af97d0a
--- /dev/null
+++ b/widget/cocoa/RectTextureImage.mm
@@ -0,0 +1,171 @@
+/* -*- Mode: objc; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "RectTextureImage.h"
+
+#include "gfxUtils.h"
+#include "GLContextCGL.h"
+#include "mozilla/layers/GLManager.h"
+#include "mozilla/gfx/MacIOSurface.h"
+#include "OGLShaderProgram.h"
+#include "ScopedGLHelpers.h"
+
+namespace mozilla {
+namespace widget {
+
+RectTextureImage::RectTextureImage()
+  : mGLContext(nullptr)
+  , mTexture(0)
+  , mInUpdate(false)
+{
+}
+
+RectTextureImage::~RectTextureImage()
+{
+  DeleteTexture();
+}
+
+already_AddRefed<gfx::DrawTarget>
+RectTextureImage::BeginUpdate(const LayoutDeviceIntSize& aNewSize,
+                              const LayoutDeviceIntRegion& aDirtyRegion)
+{
+  MOZ_ASSERT(!mInUpdate, "Beginning update during update!");
+  mUpdateRegion = aDirtyRegion;
+  bool needRecreate = false;
+  if (aNewSize != mBufferSize) {
+    mBufferSize = aNewSize;
+    mUpdateRegion =
+      LayoutDeviceIntRect(LayoutDeviceIntPoint(0, 0), aNewSize);
+    needRecreate = true;
+  }
+
+  if (mUpdateRegion.IsEmpty()) {
+    return nullptr;
+  }
+
+  if (!mIOSurface || needRecreate) {
+    DeleteTexture();
+    mIOSurface = MacIOSurface::CreateIOSurface(mBufferSize.width,
+                                               mBufferSize.height);
+
+    if (!mIOSurface) {
+      return nullptr;
+    }
+  }
+
+  mInUpdate = true;
+
+  mIOSurface->Lock(false);
+  unsigned char* ioData = (unsigned char*)mIOSurface->GetBaseAddress();
+  gfx::IntSize size(mBufferSize.width, mBufferSize.height);
+  int32_t stride = mIOSurface->GetBytesPerRow();
+  gfx::SurfaceFormat format = gfx::SurfaceFormat::B8G8R8A8;
+  RefPtr<gfx::DrawTarget> drawTarget =
+    gfx::Factory::CreateDrawTargetForData(gfx::BackendType::SKIA,
+                                          ioData, size,
+                                          stride, format);
+  return drawTarget.forget();
+}
+
+void
+RectTextureImage::EndUpdate()
+{
+  MOZ_ASSERT(mInUpdate, "Ending update while not in update");
+  mIOSurface->Unlock(false);
+  mInUpdate = false;
+}
+
+void
+RectTextureImage::UpdateFromCGContext(const LayoutDeviceIntSize& aNewSize,
+                                      const LayoutDeviceIntRegion& aDirtyRegion,
+                                      CGContextRef aCGContext)
+{
+  gfx::IntSize size = gfx::IntSize(CGBitmapContextGetWidth(aCGContext),
+                                   CGBitmapContextGetHeight(aCGContext));
+  RefPtr<gfx::DrawTarget> dt = BeginUpdate(aNewSize, aDirtyRegion);
+  if (dt) {
+    gfx::Rect rect(0, 0, size.width, size.height);
+    gfxUtils::ClipToRegion(dt, GetUpdateRegion().ToUnknownRegion());
+    RefPtr<gfx::SourceSurface> sourceSurface =
+      dt->CreateSourceSurfaceFromData(static_cast<uint8_t *>(CGBitmapContextGetData(aCGContext)),
+                                      size,
+                                      CGBitmapContextGetBytesPerRow(aCGContext),
+                                      gfx::SurfaceFormat::B8G8R8A8);
+    dt->DrawSurface(sourceSurface, rect, rect,
+                    gfx::DrawSurfaceOptions(),
+                    gfx::DrawOptions(1.0, gfx::CompositionOp::OP_SOURCE));
+    dt->PopClip();
+    EndUpdate();
+  }
+}
+
+void
+RectTextureImage::Draw(layers::GLManager* aManager,
+                       const LayoutDeviceIntPoint& aLocation,
+                       const gfx::Matrix4x4& aTransform)
+{
+  gl::GLContext* gl = aManager->gl();
+
+  BindIOSurfaceToTexture(gl);
+
+  layers::ShaderProgramOGL* program =
+    aManager->GetProgram(LOCAL_GL_TEXTURE_RECTANGLE_ARB,
+                         gfx::SurfaceFormat::R8G8B8A8);
+
+  gl->fActiveTexture(LOCAL_GL_TEXTURE0);
+  gl::ScopedBindTexture texture(gl, mTexture, LOCAL_GL_TEXTURE_RECTANGLE_ARB);
+
+  aManager->ActivateProgram(program);
+  program->SetProjectionMatrix(aManager->GetProjMatrix());
+  program->SetLayerTransform(gfx::Matrix4x4(aTransform).PostTranslate(aLocation.x, aLocation.y, 0));
+  program->SetTextureTransform(gfx::Matrix4x4());
+  program->SetRenderOffset(nsIntPoint(0, 0));
+  program->SetTexCoordMultiplier(mBufferSize.width, mBufferSize.height);
+  program->SetTextureUnit(0);
+
+  aManager->BindAndDrawQuad(program,
+                            gfx::Rect(0.0, 0.0, mBufferSize.width, mBufferSize.height),
+                            gfx::Rect(0.0, 0.0, 1.0f, 1.0f));
+}
+
+void
+RectTextureImage::DeleteTexture()
+{
+  if (mTexture) {
+    MOZ_ASSERT(mGLContext);
+    mGLContext->MakeCurrent();
+    mGLContext->fDeleteTextures(1, &mTexture);
+    mTexture = 0;
+  }
+}
+
+void
+RectTextureImage::BindIOSurfaceToTexture(gl::GLContext* aGL)
+{
+  if (!mTexture) {
+    MOZ_ASSERT(aGL);
+    aGL->fGenTextures(1, &mTexture);
+    aGL->fActiveTexture(LOCAL_GL_TEXTURE0);
+    gl::ScopedBindTexture texture(aGL, mTexture, LOCAL_GL_TEXTURE_RECTANGLE_ARB);
+    aGL->fTexParameteri(LOCAL_GL_TEXTURE_RECTANGLE_ARB,
+                        LOCAL_GL_TEXTURE_MIN_FILTER,
+                        LOCAL_GL_LINEAR);
+    aGL->fTexParameteri(LOCAL_GL_TEXTURE_RECTANGLE_ARB,
+                        LOCAL_GL_TEXTURE_MAG_FILTER,
+                        LOCAL_GL_LINEAR);
+    aGL->fTexParameteri(LOCAL_GL_TEXTURE_RECTANGLE_ARB,
+                        LOCAL_GL_TEXTURE_WRAP_T,
+                        LOCAL_GL_CLAMP_TO_EDGE);
+    aGL->fTexParameteri(LOCAL_GL_TEXTURE_RECTANGLE_ARB,
+                        LOCAL_GL_TEXTURE_WRAP_S,
+                        LOCAL_GL_CLAMP_TO_EDGE);
+
+    mIOSurface->CGLTexImageIOSurface2D(gl::GLContextCGL::Cast(aGL)->GetCGLContext());
+    mGLContext = aGL;
+  }
+}
+
+} // namespace widget
+} // namespace mozilla
diff --git a/widget/cocoa/SwipeTracker.h b/widget/cocoa/SwipeTracker.h
new file mode 100644
index 0000000000..78940d15cc
--- /dev/null
+++ b/widget/cocoa/SwipeTracker.h
@@ -0,0 +1,95 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef SwipeTracker_h
+#define SwipeTracker_h
+
+#include "EventForwards.h"
+#include "mozilla/layers/AxisPhysicsMSDModel.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/TimeStamp.h"
+#include "nsRefreshDriver.h"
+#include "Units.h"
+
+class nsIPresShell;
+
+namespace mozilla {
+
+class PanGestureInput;
+
+/**
+ * SwipeTracker turns PanGestureInput events into swipe events
+ * (WidgetSimpleGestureEvent) and dispatches them into Gecko.
+ * The swiping behavior mirrors the behavior of the Cocoa API
+ * -[NSEvent trackSwipeEventWithOptions:dampenAmountThresholdMin:max:usingHandler:].
+ * The advantage of using this class over the Cocoa API is that this class
+ * properly supports submitting queued up events to it, and that it hopefully
+ * doesn't intermittently break scrolling the way the Cocoa API does (bug 927702).
+ *
+ * The swipe direction is either left or right. It is determined before the
+ * SwipeTracker is created and stays fixed during the swipe.
+ * During the swipe, the swipe has a current "value" which is between 0 and the
+ * target value. The target value is either 1 (swiping left) or -1 (swiping
+ * right) - see SwipeSuccessTargetValue().
+ * A swipe can either succeed or fail. If it succeeds, the swipe animation
+ * animates towards the success target value; if it fails, it animates back to
+ * a value of 0. A swipe can only succeed if the user is swiping in an allowed
+ * direction. (Since both the allowed directions and the swipe direction are
+ * known at swipe start time, it's clear from the beginning whether a swipe is
+ * doomed to fail. In that case, the purpose of the SwipeTracker is to simulate
+ * a bounce-back animation.)
+ */
+class SwipeTracker final : public nsARefreshObserver {
+public:
+  NS_INLINE_DECL_REFCOUNTING(SwipeTracker, override)
+
+  SwipeTracker(nsChildView& aWidget,
+               const PanGestureInput& aSwipeStartEvent,
+               uint32_t aAllowedDirections,
+               uint32_t aSwipeDirection);
+
+  void Destroy();
+
+  nsEventStatus ProcessEvent(const PanGestureInput& aEvent);
+  void CancelSwipe();
+
+  static WidgetSimpleGestureEvent
+    CreateSwipeGestureEvent(EventMessage aMsg, nsIWidget* aWidget,
+                            const LayoutDeviceIntPoint& aPosition);
+
+
+  // nsARefreshObserver
+  void WillRefresh(mozilla::TimeStamp aTime) override;
+
+protected:
+  ~SwipeTracker();
+
+  bool SwipingInAllowedDirection() const { return mAllowedDirections & mSwipeDirection; }
+  double SwipeSuccessTargetValue() const;
+  double ClampToAllowedRange(double aGestureAmount) const;
+  bool ComputeSwipeSuccess() const;
+  void StartAnimating(double aTargetValue);
+  void SwipeFinished();
+  void UnregisterFromRefreshDriver();
+  bool SendSwipeEvent(EventMessage aMsg, uint32_t aDirection, double aDelta);
+
+  nsChildView& mWidget;
+  RefPtr<nsRefreshDriver> mRefreshDriver;
+  layers::AxisPhysicsMSDModel mAxis;
+  const LayoutDeviceIntPoint mEventPosition;
+  TimeStamp mLastEventTimeStamp;
+  TimeStamp mLastAnimationFrameTime;
+  const uint32_t mAllowedDirections;
+  const uint32_t mSwipeDirection;
+  double mGestureAmount;
+  double mCurrentVelocity;
+  bool mEventsAreControllingSwipe;
+  bool mEventsHaveStartedNewGesture;
+  bool mRegisteredWithRefreshDriver;
+};
+
+} // namespace mozilla
+
+#endif // SwipeTracker_h
diff --git a/widget/cocoa/SwipeTracker.mm b/widget/cocoa/SwipeTracker.mm
new file mode 100644
index 0000000000..51169171a4
--- /dev/null
+++ b/widget/cocoa/SwipeTracker.mm
@@ -0,0 +1,219 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "SwipeTracker.h"
+
+#include "InputData.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/TouchEvents.h"
+#include "nsAlgorithm.h"
+#include "nsChildView.h"
+#include "UnitTransforms.h"
+
+// These values were tweaked to make the physics feel similar to the native swipe.
+static const double kSpringForce = 250.0;
+static const double kVelocityTwitchTolerance = 0.0000001;
+static const double kWholePagePixelSize = 1000.0;
+static const double kRubberBandResistanceFactor = 4.0;
+static const double kSwipeSuccessThreshold = 0.25;
+static const double kSwipeSuccessVelocityContribution = 0.3;
+
+namespace mozilla {
+
+static already_AddRefed<nsRefreshDriver>
+GetRefreshDriver(nsIWidget& aWidget)
+{
+  nsIWidgetListener* widgetListener = aWidget.GetWidgetListener();
+  nsIPresShell* presShell = widgetListener ? widgetListener->GetPresShell() : nullptr;
+  nsPresContext* presContext = presShell ? presShell->GetPresContext() : nullptr;
+  RefPtr<nsRefreshDriver> refreshDriver = presContext ? presContext->RefreshDriver() : nullptr;
+  return refreshDriver.forget();
+}
+
+SwipeTracker::SwipeTracker(nsChildView& aWidget,
+                           const PanGestureInput& aSwipeStartEvent,
+                           uint32_t aAllowedDirections,
+                           uint32_t aSwipeDirection)
+  : mWidget(aWidget)
+  , mRefreshDriver(GetRefreshDriver(mWidget))
+  , mAxis(0.0, 0.0, 0.0, kSpringForce, 1.0)
+  , mEventPosition(RoundedToInt(ViewAs<LayoutDevicePixel>(aSwipeStartEvent.mPanStartPoint,
+                                  PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent)))
+  , mLastEventTimeStamp(aSwipeStartEvent.mTimeStamp)
+  , mAllowedDirections(aAllowedDirections)
+  , mSwipeDirection(aSwipeDirection)
+  , mGestureAmount(0.0)
+  , mCurrentVelocity(0.0)
+  , mEventsAreControllingSwipe(true)
+  , mEventsHaveStartedNewGesture(false)
+  , mRegisteredWithRefreshDriver(false)
+{
+  SendSwipeEvent(eSwipeGestureStart, 0, 0.0);
+  ProcessEvent(aSwipeStartEvent);
+}
+
+void
+SwipeTracker::Destroy()
+{
+  UnregisterFromRefreshDriver();
+}
+
+SwipeTracker::~SwipeTracker()
+{
+  MOZ_ASSERT(!mRegisteredWithRefreshDriver, "Destroy needs to be called before deallocating");
+}
+
+double
+SwipeTracker::SwipeSuccessTargetValue() const
+{
+  return (mSwipeDirection == nsIDOMSimpleGestureEvent::DIRECTION_RIGHT) ? -1.0 : 1.0;
+}
+
+double
+SwipeTracker::ClampToAllowedRange(double aGestureAmount) const
+{
+  // gestureAmount needs to stay between -1 and 0 when swiping right and
+  // between 0 and 1 when swiping left.
+  double min = (mSwipeDirection == nsIDOMSimpleGestureEvent::DIRECTION_RIGHT) ? -1.0 : 0.0;
+  double max = (mSwipeDirection == nsIDOMSimpleGestureEvent::DIRECTION_LEFT) ? 1.0 : 0.0;
+  return clamped(aGestureAmount, min, max);
+}
+
+bool
+SwipeTracker::ComputeSwipeSuccess() const
+{
+  double targetValue = SwipeSuccessTargetValue();
+
+  // If the fingers were moving away from the target direction when they were
+  // lifted from the touchpad, abort the swipe.
+  if (mCurrentVelocity * targetValue < -kVelocityTwitchTolerance) {
+    return false;
+  }
+
+  return (mGestureAmount * targetValue +
+          mCurrentVelocity * targetValue * kSwipeSuccessVelocityContribution) >= kSwipeSuccessThreshold;
+}
+
+nsEventStatus
+SwipeTracker::ProcessEvent(const PanGestureInput& aEvent)
+{
+  // If the fingers have already been lifted, don't process this event for swiping.
+  if (!mEventsAreControllingSwipe) {
+    // Return nsEventStatus_eConsumeNoDefault for events from the swipe gesture
+    // and nsEventStatus_eIgnore for events of subsequent scroll gestures.
+    if (aEvent.mType == PanGestureInput::PANGESTURE_MAYSTART ||
+        aEvent.mType == PanGestureInput::PANGESTURE_START) {
+      mEventsHaveStartedNewGesture = true;
+    }
+    return mEventsHaveStartedNewGesture ? nsEventStatus_eIgnore : nsEventStatus_eConsumeNoDefault;
+  }
+
+  double delta = -aEvent.mPanDisplacement.x / mWidget.BackingScaleFactor() / kWholePagePixelSize;
+  if (!SwipingInAllowedDirection()) {
+    delta /= kRubberBandResistanceFactor;
+  }
+  mGestureAmount = ClampToAllowedRange(mGestureAmount + delta);
+  SendSwipeEvent(eSwipeGestureUpdate, 0, mGestureAmount);
+
+  if (aEvent.mType != PanGestureInput::PANGESTURE_END) {
+    double elapsedSeconds = std::max(0.008, (aEvent.mTimeStamp - mLastEventTimeStamp).ToSeconds());
+    mCurrentVelocity = delta / elapsedSeconds;
+    mLastEventTimeStamp = aEvent.mTimeStamp;
+  } else {
+    mEventsAreControllingSwipe = false;
+    bool didSwipeSucceed = SwipingInAllowedDirection() && ComputeSwipeSuccess();
+    double targetValue = 0.0;
+    if (didSwipeSucceed) {
+      SendSwipeEvent(eSwipeGesture, mSwipeDirection, 0.0);
+      targetValue = SwipeSuccessTargetValue();
+    }
+    StartAnimating(targetValue);
+  }
+
+  return nsEventStatus_eConsumeNoDefault;
+}
+
+void
+SwipeTracker::StartAnimating(double aTargetValue)
+{
+  mAxis.SetPosition(mGestureAmount);
+  mAxis.SetDestination(aTargetValue);
+  mAxis.SetVelocity(mCurrentVelocity);
+
+  mLastAnimationFrameTime = TimeStamp::Now();
+
+  // Add ourselves as a refresh driver observer. The refresh driver
+  // will call WillRefresh for each animation frame until we
+  // unregister ourselves.
+  MOZ_ASSERT(!mRegisteredWithRefreshDriver);
+  if (mRefreshDriver) {
+    mRefreshDriver->AddRefreshObserver(this, Flush_Style);
+    mRegisteredWithRefreshDriver = true;
+  }
+}
+
+void
+SwipeTracker::WillRefresh(mozilla::TimeStamp aTime)
+{
+  TimeStamp now = TimeStamp::Now();
+  mAxis.Simulate(now - mLastAnimationFrameTime);
+  mLastAnimationFrameTime = now;
+
+  bool isFinished = mAxis.IsFinished(1.0 / kWholePagePixelSize);
+  mGestureAmount = (isFinished ? mAxis.GetDestination() : mAxis.GetPosition());
+  SendSwipeEvent(eSwipeGestureUpdate, 0, mGestureAmount);
+
+  if (isFinished) {
+    UnregisterFromRefreshDriver();
+    SwipeFinished();
+  }
+}
+
+void
+SwipeTracker::CancelSwipe()
+{
+  SendSwipeEvent(eSwipeGestureEnd, 0, 0.0);
+}
+
+void SwipeTracker::SwipeFinished()
+{
+  SendSwipeEvent(eSwipeGestureEnd, 0, 0.0);
+  mWidget.SwipeFinished();
+}
+
+void
+SwipeTracker::UnregisterFromRefreshDriver()
+{
+  if (mRegisteredWithRefreshDriver) {
+    MOZ_ASSERT(mRefreshDriver, "How were we able to register, then?");
+    mRefreshDriver->RemoveRefreshObserver(this, Flush_Style);
+  }
+  mRegisteredWithRefreshDriver = false;
+}
+
+/* static */ WidgetSimpleGestureEvent
+SwipeTracker::CreateSwipeGestureEvent(EventMessage aMsg, nsIWidget* aWidget,
+                                      const LayoutDeviceIntPoint& aPosition)
+{
+  WidgetSimpleGestureEvent geckoEvent(true, aMsg, aWidget);
+  geckoEvent.mModifiers = 0;
+  geckoEvent.mTimeStamp = TimeStamp::Now();
+  geckoEvent.mRefPoint = aPosition;
+  geckoEvent.buttons = 0;
+  return geckoEvent;
+}
+
+bool
+SwipeTracker::SendSwipeEvent(EventMessage aMsg, uint32_t aDirection, double aDelta)
+{
+  WidgetSimpleGestureEvent geckoEvent =
+    CreateSwipeGestureEvent(aMsg, &mWidget, mEventPosition);
+  geckoEvent.mDirection = aDirection;
+  geckoEvent.mDelta = aDelta;
+  geckoEvent.mAllowedDirections = mAllowedDirections;
+  return mWidget.DispatchWindowEvent(geckoEvent);
+}
+
+} // namespace mozilla
diff --git a/widget/cocoa/TextInputHandler.h b/widget/cocoa/TextInputHandler.h
new file mode 100644
index 0000000000..86da354abb
--- /dev/null
+++ b/widget/cocoa/TextInputHandler.h
@@ -0,0 +1,1194 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef TextInputHandler_h_
+#define TextInputHandler_h_
+
+#include "nsCocoaUtils.h"
+
+#import <Carbon/Carbon.h>
+#import <Cocoa/Cocoa.h>
+#include "mozView.h"
+#include "nsString.h"
+#include "nsCOMPtr.h"
+#include "nsITimer.h"
+#include "nsTArray.h"
+#include "mozilla/EventForwards.h"
+#include "mozilla/TextEventDispatcherListener.h"
+#include "WritingModes.h"
+
+class nsChildView;
+
+namespace mozilla {
+namespace widget {
+
+// Key code constants
+enum
+{
+#if !defined(MAC_OS_X_VERSION_10_12) || \
+  MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_12
+  kVK_RightCommand    = 0x36, // right command key
+#endif
+
+  kVK_PC_PrintScreen     = kVK_F13,
+  kVK_PC_ScrollLock      = kVK_F14,
+  kVK_PC_Pause           = kVK_F15,
+
+  kVK_PC_Insert          = kVK_Help,
+  kVK_PC_Backspace       = kVK_Delete,
+  kVK_PC_Delete          = kVK_ForwardDelete,
+
+  kVK_PC_ContextMenu     = 0x6E,
+
+  kVK_Powerbook_KeypadEnter = 0x34  // Enter on Powerbook's keyboard is different
+};
+
+/**
+ * TISInputSourceWrapper is a wrapper for the TISInputSourceRef.  If we get the
+ * TISInputSourceRef from InputSourceID, we need to release the CFArray instance
+ * which is returned by TISCreateInputSourceList.  However, when we release the
+ * list, we cannot access the TISInputSourceRef.  So, it's not usable, and it
+ * may cause the memory leak bugs.  nsTISInputSource automatically releases the
+ * list when the instance is destroyed.
+ */
+class TISInputSourceWrapper
+{
+public:
+  static TISInputSourceWrapper& CurrentInputSource();
+  /**
+   * Shutdown() should be called when nobody doesn't need to use this class.
+   */
+  static void Shutdown();
+
+  TISInputSourceWrapper()
+  {
+    mInputSourceList = nullptr;
+    Clear();
+  }
+
+  explicit TISInputSourceWrapper(const char* aID)
+  {
+    mInputSourceList = nullptr;
+    InitByInputSourceID(aID);
+  }
+
+  explicit TISInputSourceWrapper(SInt32 aLayoutID)
+  {
+    mInputSourceList = nullptr;
+    InitByLayoutID(aLayoutID);
+  }
+
+  explicit TISInputSourceWrapper(TISInputSourceRef aInputSource)
+  {
+    mInputSourceList = nullptr;
+    InitByTISInputSourceRef(aInputSource);
+  }
+
+  ~TISInputSourceWrapper() { Clear(); }
+
+  void InitByInputSourceID(const char* aID);
+  void InitByInputSourceID(const nsAFlatString &aID);
+  void InitByInputSourceID(const CFStringRef aID);
+  /**
+   * InitByLayoutID() initializes the keyboard layout by the layout ID.
+   *
+   * @param aLayoutID             An ID of keyboard layout.
+   *                                0: US
+   *                                1: Greek
+   *                                2: German
+   *                                3: Swedish-Pro
+   *                                4: Dvorak-Qwerty Cmd
+   *                                5: Thai
+   *                                6: Arabic
+   *                                7: French
+   *                                8: Hebrew
+   *                                9: Lithuanian
+   *                               10: Norwegian
+   *                               11: Spanish
+   * @param aOverrideKeyboard     When testing set to TRUE, otherwise, set to
+   *                              FALSE.  When TRUE, we use an ANSI keyboard
+   *                              instead of the actual keyboard.
+   */
+  void InitByLayoutID(SInt32 aLayoutID, bool aOverrideKeyboard = false);
+  void InitByCurrentInputSource();
+  void InitByCurrentKeyboardLayout();
+  void InitByCurrentASCIICapableInputSource();
+  void InitByCurrentASCIICapableKeyboardLayout();
+  void InitByCurrentInputMethodKeyboardLayoutOverride();
+  void InitByTISInputSourceRef(TISInputSourceRef aInputSource);
+  void InitByLanguage(CFStringRef aLanguage);
+
+  /**
+   * If the instance is initialized with a keyboard layout input source,
+   * returns it.
+   * If the instance is initialized with an IME mode input source, the result
+   * references the keyboard layout for the IME mode.  However, this can be
+   * initialized only when the IME mode is actually selected.  I.e, if IME mode
+   * input source is initialized with LayoutID or SourceID, this returns null.
+   */
+  TISInputSourceRef GetKeyboardLayoutInputSource() const
+  {
+    return mKeyboardLayout;
+  }
+  const UCKeyboardLayout* GetUCKeyboardLayout();
+
+  bool IsOpenedIMEMode();
+  bool IsIMEMode();
+  bool IsKeyboardLayout();
+
+  bool IsASCIICapable()
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetBoolProperty(kTISPropertyInputSourceIsASCIICapable);
+  }
+
+  bool IsEnabled()
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetBoolProperty(kTISPropertyInputSourceIsEnabled);
+  }
+
+  bool GetLanguageList(CFArrayRef &aLanguageList);
+  bool GetPrimaryLanguage(CFStringRef &aPrimaryLanguage);
+  bool GetPrimaryLanguage(nsAString &aPrimaryLanguage);
+
+  bool GetLocalizedName(CFStringRef &aName)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyLocalizedName, aName);
+  }
+
+  bool GetLocalizedName(nsAString &aName)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyLocalizedName, aName);
+  }
+
+  bool GetInputSourceID(CFStringRef &aID)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyInputSourceID, aID);
+  }
+
+  bool GetInputSourceID(nsAString &aID)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyInputSourceID, aID);
+  }
+
+  bool GetBundleID(CFStringRef &aBundleID)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyBundleID, aBundleID);
+  }
+
+  bool GetBundleID(nsAString &aBundleID)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyBundleID, aBundleID);
+  }
+
+  bool GetInputSourceType(CFStringRef &aType)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyInputSourceType, aType);
+  }
+
+  bool GetInputSourceType(nsAString &aType)
+  {
+    NS_ENSURE_TRUE(mInputSource, false);
+    return GetStringProperty(kTISPropertyInputSourceType, aType);
+  }
+
+  bool IsForRTLLanguage();
+  bool IsInitializedByCurrentInputSource();
+
+  enum {
+    // 40 is an actual result of the ::LMGetKbdType() when we connect an
+    // unknown keyboard and set the keyboard type to ANSI manually on the
+    // set up dialog.
+    eKbdType_ANSI = 40
+  };
+
+  void Select();
+  void Clear();
+
+  /**
+   * InitKeyEvent() initializes aKeyEvent for aNativeKeyEvent.
+   *
+   * @param aNativeKeyEvent       A native key event for which you want to
+   *                              dispatch a Gecko key event.
+   * @param aKeyEvent             The result -- a Gecko key event initialized
+   *                              from the native key event.
+   * @param aInsertString         If caller expects that the event will cause
+   *                              a character to be input (say in an editor),
+   *                              the caller should set this.  Otherwise,
+   *                              if caller sets null to this, this method will
+   *                              compute the character to be input from
+   *                              characters of aNativeKeyEvent.
+   */
+  void InitKeyEvent(NSEvent *aNativeKeyEvent, WidgetKeyboardEvent& aKeyEvent,
+                    const nsAString *aInsertString = nullptr);
+
+  /**
+   * WillDispatchKeyboardEvent() computes aKeyEvent.mAlternativeCharCodes and
+   * recompute aKeyEvent.mCharCode if it's necessary.
+   *
+   * @param aNativeKeyEvent       A native key event for which you want to
+   *                              dispatch a Gecko key event.
+   * @param aInsertString         If caller expects that the event will cause
+   *                              a character to be input (say in an editor),
+   *                              the caller should set this.  Otherwise,
+   *                              if caller sets null to this, this method will
+   *                              compute the character to be input from
+   *                              characters of aNativeKeyEvent.
+   * @param aKeyEvent             The result -- a Gecko key event initialized
+   *                              from the native key event.  This must be
+   *                              eKeyPress event.
+   */
+  void WillDispatchKeyboardEvent(NSEvent* aNativeKeyEvent,
+                                 const nsAString* aInsertString,
+                                 WidgetKeyboardEvent& aKeyEvent);
+
+  /**
+   * ComputeGeckoKeyCode() returns Gecko keycode for aNativeKeyCode on current
+   * keyboard layout.
+   *
+   * @param aNativeKeyCode        A native keycode.
+   * @param aKbType               A native Keyboard Type value.  Typically,
+   *                              this is a result of ::LMGetKbdType().
+   * @param aCmdIsPressed         TRUE if Cmd key is pressed.  Otherwise, FALSE.
+   * @return                      The computed Gecko keycode.
+   */
+  uint32_t ComputeGeckoKeyCode(UInt32 aNativeKeyCode, UInt32 aKbType,
+                               bool aCmdIsPressed);
+
+  /**
+   * ComputeGeckoKeyNameIndex() returns Gecko key name index for the key.
+   *
+   * @param aNativeKeyCode        A native keycode.
+   */
+  static KeyNameIndex ComputeGeckoKeyNameIndex(UInt32 aNativeKeyCode);
+
+  /**
+   * ComputeGeckoCodeNameIndex() returns Gecko code name index for the key.
+   *
+   * @param aNativeKeyCode        A native keycode.
+   */
+  static CodeNameIndex ComputeGeckoCodeNameIndex(UInt32 aNativeKeyCode);
+
+protected:
+  /**
+   * TranslateToString() computes the inputted text from the native keyCode,
+   * modifier flags and keyboard type.
+   *
+   * @param aKeyCode              A native keyCode.
+   * @param aModifiers            Combination of native modifier flags.
+   * @param aKbType               A native Keyboard Type value.  Typically,
+   *                              this is a result of ::LMGetKbdType().
+   * @param aStr                  Result, i.e., inputted text.
+   *                              The result can be two or more characters.
+   * @return                      If succeeded, TRUE.  Otherwise, FALSE.
+   *                              Even if TRUE, aStr can be empty string.
+   */
+  bool TranslateToString(UInt32 aKeyCode, UInt32 aModifiers,
+                           UInt32 aKbType, nsAString &aStr);
+
+  /**
+   * TranslateToChar() computes the inputted character from the native keyCode,
+   * modifier flags and keyboard type.  If two or more characters would be
+   * input, this returns 0.
+   *
+   * @param aKeyCode              A native keyCode.
+   * @param aModifiers            Combination of native modifier flags.
+   * @param aKbType               A native Keyboard Type value.  Typically,
+   *                              this is a result of ::LMGetKbdType().
+   * @return                      If succeeded and the result is one character,
+   *                              returns the charCode of it.  Otherwise,
+   *                              returns 0.
+   */
+  uint32_t TranslateToChar(UInt32 aKeyCode, UInt32 aModifiers, UInt32 aKbType);
+
+  /**
+   * ComputeInsertString() computes string to be inserted with the key event.
+   *
+   * @param aNativeKeyEvent     The native key event which causes our keyboard
+   *                            event(s).
+   * @param aKeyEvent           A Gecko key event which was partially
+   *                            initialized with aNativeKeyEvent.
+   * @param aInsertString       The string to be inputting by aNativeKeyEvent.
+   *                            This should be specified by InsertText().
+   *                            In other words, if the key event doesn't cause
+   *                            a call of InsertText(), this can be nullptr.
+   * @param aResult             The string which should be set to charCode of
+   *                            keypress event(s).
+   */
+  void ComputeInsertStringForCharCode(NSEvent* aNativeKeyEvent,
+                                      const WidgetKeyboardEvent& aKeyEvent,
+                                      const nsAString* aInsertString,
+                                      nsAString& aResult);
+
+  /**
+   * IsPrintableKeyEvent() returns true if aNativeKeyEvent is caused by
+   * a printable key.  Otherwise, returns false.
+   */
+  bool IsPrintableKeyEvent(NSEvent* aNativeKeyEvent) const;
+
+  /**
+   * GetKbdType() returns physical keyboard type.
+   */
+  UInt32 GetKbdType() const;
+
+  bool GetBoolProperty(const CFStringRef aKey);
+  bool GetStringProperty(const CFStringRef aKey, CFStringRef &aStr);
+  bool GetStringProperty(const CFStringRef aKey, nsAString &aStr);
+
+  TISInputSourceRef mInputSource;
+  TISInputSourceRef mKeyboardLayout;
+  CFArrayRef mInputSourceList;
+  const UCKeyboardLayout* mUCKeyboardLayout;
+  int8_t mIsRTL;
+
+  bool mOverrideKeyboard;
+
+  static TISInputSourceWrapper* sCurrentInputSource;
+};
+
+/**
+ * TextInputHandlerBase is a base class of IMEInputHandler and TextInputHandler.
+ * Utility methods should be implemented this level.
+ */
+
+class TextInputHandlerBase : public TextEventDispatcherListener
+{
+public:
+  /**
+   * Other TextEventDispatcherListener methods should be implemented in
+   * IMEInputHandler.
+   */
+  NS_DECL_ISUPPORTS
+
+  /**
+   * DispatchEvent() dispatches aEvent on mWidget.
+   *
+   * @param aEvent                An event which you want to dispatch.
+   * @return                      TRUE if the event is consumed by web contents
+   *                              or chrome contents.  Otherwise, FALSE.
+   */
+  bool DispatchEvent(WidgetGUIEvent& aEvent);
+
+  /**
+   * SetSelection() dispatches eSetSelection event for the aRange.
+   *
+   * @param aRange                The range which will be selected.
+   * @return                      TRUE if setting selection is succeeded and
+   *                              the widget hasn't been destroyed.
+   *                              Otherwise, FALSE.
+   */
+  bool SetSelection(NSRange& aRange);
+
+  /**
+   * InitKeyEvent() initializes aKeyEvent for aNativeKeyEvent.
+   *
+   * @param aNativeKeyEvent       A native key event for which you want to
+   *                              dispatch a Gecko key event.
+   * @param aKeyEvent             The result -- a Gecko key event initialized
+   *                              from the native key event.
+   * @param aInsertString         If caller expects that the event will cause
+   *                              a character to be input (say in an editor),
+   *                              the caller should set this.  Otherwise,
+   *                              if caller sets null to this, this method will
+   *                              compute the character to be input from
+   *                              characters of aNativeKeyEvent.
+   */
+  void InitKeyEvent(NSEvent *aNativeKeyEvent, WidgetKeyboardEvent& aKeyEvent,
+                    const nsAString *aInsertString = nullptr);
+
+  /**
+   * SynthesizeNativeKeyEvent() is an implementation of
+   * nsIWidget::SynthesizeNativeKeyEvent().  See the document in nsIWidget.h
+   * for the detail.
+   */
+  nsresult SynthesizeNativeKeyEvent(int32_t aNativeKeyboardLayout,
+                                    int32_t aNativeKeyCode,
+                                    uint32_t aModifierFlags,
+                                    const nsAString& aCharacters,
+                                    const nsAString& aUnmodifiedCharacters);
+
+  /**
+   * Utility method intended for testing. Attempts to construct a native key
+   * event that would have been generated during an actual key press. This
+   * *does not dispatch* the native event. Instead, it is attached to the
+   * |mNativeKeyEvent| field of the Gecko event that is passed in.
+   * @param aKeyEvent  Gecko key event to attach the native event to
+   */
+  NS_IMETHOD AttachNativeKeyEvent(WidgetKeyboardEvent& aKeyEvent);
+
+  /**
+   * GetWindowLevel() returns the window level of current focused (in Gecko)
+   * window.  E.g., if an <input> element in XUL panel has focus, this returns
+   * the XUL panel's window level.
+   */
+  NSInteger GetWindowLevel();
+
+  /**
+   * IsSpecialGeckoKey() checks whether aNativeKeyCode is mapped to a special
+   * Gecko keyCode.  A key is "special" if it isn't used for text input.
+   *
+   * @param aNativeKeyCode        A native keycode.
+   * @return                      If the keycode is mapped to a special key,
+   *                              TRUE.  Otherwise, FALSE.
+   */
+  static bool IsSpecialGeckoKey(UInt32 aNativeKeyCode);
+
+
+  /**
+   * EnableSecureEventInput() and DisableSecureEventInput() wrap the Carbon
+   * Event Manager APIs with the same names.  In addition they keep track of
+   * how many times we've called them (in the same process) -- unlike the
+   * Carbon Event Manager APIs, which only keep track of how many times they've
+   * been called from any and all processes.
+   *
+   * The Carbon Event Manager's IsSecureEventInputEnabled() returns whether
+   * secure event input mode is enabled (in any process).  This class's
+   * IsSecureEventInputEnabled() returns whether we've made any calls to
+   * EnableSecureEventInput() that are not (yet) offset by the calls we've
+   * made to DisableSecureEventInput().
+   */
+  static void EnableSecureEventInput();
+  static void DisableSecureEventInput();
+  static bool IsSecureEventInputEnabled();
+
+  /**
+   * EnsureSecureEventInputDisabled() calls DisableSecureEventInput() until
+   * our call count becomes 0.
+   */
+  static void EnsureSecureEventInputDisabled();
+
+public:
+   /**
+   * mWidget must not be destroyed without OnDestroyWidget being called.
+   *
+   * @param aDestroyingWidget     Destroying widget.  This might not be mWidget.
+   * @return                      This result doesn't have any meaning for
+   *                              callers.  When aDstroyingWidget isn't the same
+   *                              as mWidget, FALSE.  Then, inherited methods in
+   *                              sub classes should return from this method
+   *                              without cleaning up.
+   */
+  virtual bool OnDestroyWidget(nsChildView* aDestroyingWidget);
+
+protected:
+  // The creator of this instance, client and its text event dispatcher.
+  // These members must not be nullptr after initialized until
+  // OnDestroyWidget() is called.
+  nsChildView* mWidget; // [WEAK]
+  RefPtr<TextEventDispatcher> mDispatcher;
+
+  // The native view for mWidget.
+  // This view handles the actual text inputting.
+  NSView<mozView>* mView; // [STRONG]
+
+  TextInputHandlerBase(nsChildView* aWidget, NSView<mozView> *aNativeView);
+  virtual ~TextInputHandlerBase();
+
+  bool Destroyed() { return !mWidget; }
+
+  /**
+   * mCurrentKeyEvent indicates what key event we are handling.  While
+   * handling a native keydown event, we need to store the event for insertText,
+   * doCommandBySelector and various action message handlers of NSResponder
+   * such as [NSResponder insertNewline:sender].
+   */
+  struct KeyEventState
+  {
+    // Handling native key event
+    NSEvent* mKeyEvent;
+    // String specified by InsertText().  This is not null only during a
+    // call of InsertText().
+    nsAString* mInsertString;
+    // String which are included in [mKeyEvent characters] and already handled
+    // by InsertText() call(s).
+    nsString mInsertedString;
+    // Whether keydown event was consumed by web contents or chrome contents.
+    bool mKeyDownHandled;
+    // Whether keypress event was dispatched for mKeyEvent.
+    bool mKeyPressDispatched;
+    // Whether keypress event was consumed by web contents or chrome contents.
+    bool mKeyPressHandled;
+    // Whether the key event causes other key events via IME or something.
+    bool mCausedOtherKeyEvents;
+    // Whether the key event causes composition change or committing
+    // composition.  So, even if InsertText() is called, this may be false
+    // if it dispatches keypress event.
+    bool mCompositionDispatched;
+
+    KeyEventState() : mKeyEvent(nullptr)
+    {
+      Clear();
+    }    
+
+    explicit KeyEventState(NSEvent* aNativeKeyEvent) : mKeyEvent(nullptr)
+    {
+      Clear();
+      Set(aNativeKeyEvent);
+    }
+
+    KeyEventState(const KeyEventState &aOther) = delete;
+
+    ~KeyEventState()
+    {
+      Clear();
+    }
+
+    void Set(NSEvent* aNativeKeyEvent)
+    {
+      NS_PRECONDITION(aNativeKeyEvent, "aNativeKeyEvent must not be NULL");
+      Clear();
+      mKeyEvent = [aNativeKeyEvent retain];
+    }
+
+    void Clear()
+    {
+      if (mKeyEvent) {
+        [mKeyEvent release];
+        mKeyEvent = nullptr;
+      }
+      mInsertString = nullptr;
+      mInsertedString.Truncate();
+      mKeyDownHandled = false;
+      mKeyPressDispatched = false;
+      mKeyPressHandled = false;
+      mCausedOtherKeyEvents = false;
+      mCompositionDispatched = false;
+    }
+
+    bool IsDefaultPrevented() const
+    {
+      return mKeyDownHandled || mKeyPressHandled || mCausedOtherKeyEvents ||
+             mCompositionDispatched;
+    }
+
+    bool CanDispatchKeyPressEvent() const
+    {
+      return !mKeyPressDispatched && !IsDefaultPrevented();
+    }
+
+    void InitKeyEvent(TextInputHandlerBase* aHandler,
+                      WidgetKeyboardEvent& aKeyEvent);
+
+    /**
+     * GetUnhandledString() returns characters of the event which have not been
+     * handled with InsertText() yet. For example, if there is a composition
+     * caused by a dead key press like '`' and it's committed by some key
+     * combinations like |Cmd+v|, then, the |v|'s KeyDown event's |characters|
+     * is |`v|.  Then, after |`| is committed with a call of InsertString(),
+     * this returns only 'v'.
+     */
+    void GetUnhandledString(nsAString& aUnhandledString) const;
+  };
+
+  /**
+   * Helper classes for guaranteeing cleaning mCurrentKeyEvent
+   */
+  class AutoKeyEventStateCleaner
+  {
+  public:
+    explicit AutoKeyEventStateCleaner(TextInputHandlerBase* aHandler) :
+      mHandler(aHandler)
+    {
+    }
+
+    ~AutoKeyEventStateCleaner()
+    {
+      mHandler->RemoveCurrentKeyEvent();
+    }
+  private:
+    RefPtr<TextInputHandlerBase> mHandler;
+  };
+
+  class MOZ_STACK_CLASS AutoInsertStringClearer
+  {
+  public:
+    explicit AutoInsertStringClearer(KeyEventState* aState)
+      : mState(aState)
+    {
+    }
+    ~AutoInsertStringClearer();
+
+  private:
+    KeyEventState* mState;
+  };
+
+  /**
+   * mCurrentKeyEvents stores all key events which are being processed.
+   * When we call interpretKeyEvents, IME may generate other key events.
+   * mCurrentKeyEvents[0] is the latest key event.
+   */
+  nsTArray<KeyEventState*> mCurrentKeyEvents;
+
+  /**
+   * mFirstKeyEvent must be used for first key event.  This member prevents
+   * memory fragmentation for most key events.
+   */
+  KeyEventState mFirstKeyEvent;
+
+  /**
+   * PushKeyEvent() adds the current key event to mCurrentKeyEvents.
+   */
+  KeyEventState* PushKeyEvent(NSEvent* aNativeKeyEvent)
+  {
+    uint32_t nestCount = mCurrentKeyEvents.Length();
+    for (uint32_t i = 0; i < nestCount; i++) {
+      // When the key event is caused by another key event, all key events
+      // which are being handled should be marked as "consumed".
+      mCurrentKeyEvents[i]->mCausedOtherKeyEvents = true;
+    }
+
+    KeyEventState* keyEvent = nullptr;
+    if (nestCount == 0) {
+      mFirstKeyEvent.Set(aNativeKeyEvent);
+      keyEvent = &mFirstKeyEvent;
+    } else {
+      keyEvent = new KeyEventState(aNativeKeyEvent);
+    }
+    return *mCurrentKeyEvents.AppendElement(keyEvent);
+  }
+
+  /**
+   * RemoveCurrentKeyEvent() removes the current key event from
+   * mCurrentKeyEvents.
+   */
+  void RemoveCurrentKeyEvent()
+  {
+    NS_ASSERTION(mCurrentKeyEvents.Length() > 0,
+                 "RemoveCurrentKeyEvent() is called unexpectedly");
+    KeyEventState* keyEvent = GetCurrentKeyEvent();
+    mCurrentKeyEvents.RemoveElementAt(mCurrentKeyEvents.Length() - 1);
+    if (keyEvent == &mFirstKeyEvent) {
+      keyEvent->Clear();
+    } else {
+      delete keyEvent;
+    }
+  }
+
+  /**
+   * GetCurrentKeyEvent() returns current processing key event.
+   */
+  KeyEventState* GetCurrentKeyEvent()
+  {
+    if (mCurrentKeyEvents.Length() == 0) {
+      return nullptr;
+    }
+    return mCurrentKeyEvents[mCurrentKeyEvents.Length() - 1];
+  }
+
+  struct KeyboardLayoutOverride final
+  {
+    int32_t mKeyboardLayout;
+    bool mOverrideEnabled;
+
+    KeyboardLayoutOverride() :
+      mKeyboardLayout(0), mOverrideEnabled(false)
+    {
+    }
+  };
+
+  const KeyboardLayoutOverride& KeyboardLayoutOverrideRef() const
+  {
+    return mKeyboardOverride;
+  }
+
+  /**
+   * IsPrintableChar() checks whether the unicode character is
+   * a non-printable ASCII character or not.  Note that this returns
+   * TRUE even if aChar is a non-printable UNICODE character.
+   *
+   * @param aChar                 A unicode character.
+   * @return                      TRUE if aChar is a printable ASCII character
+   *                              or a unicode character.  Otherwise, i.e,
+   *                              if aChar is a non-printable ASCII character,
+   *                              FALSE.
+   */
+  static bool IsPrintableChar(char16_t aChar);
+
+  /**
+   * IsNormalCharInputtingEvent() checks whether aKeyEvent causes text input.
+   *
+   * @param aKeyEvent             A key event.
+   * @return                      TRUE if the key event causes text input.
+   *                              Otherwise, FALSE.
+   */
+  static bool IsNormalCharInputtingEvent(const WidgetKeyboardEvent& aKeyEvent);
+
+  /**
+   * IsModifierKey() checks whether the native keyCode is for a modifier key.
+   *
+   * @param aNativeKeyCode        A native keyCode.
+   * @return                      TRUE if aNativeKeyCode is for a modifier key.
+   *                              Otherwise, FALSE.
+   */
+  static bool IsModifierKey(UInt32 aNativeKeyCode);
+
+private:
+  KeyboardLayoutOverride mKeyboardOverride;
+
+  static int32_t sSecureEventInputCount;
+};
+
+/**
+ * IMEInputHandler manages:
+ *   1. The IME/keyboard layout statement of nsChildView.
+ *   2. The IME composition statement of nsChildView.
+ * And also provides the methods which controls the current IME transaction of
+ * the instance.
+ *
+ * Note that an nsChildView handles one or more NSView's events.  E.g., even if
+ * a text editor on XUL panel element, the input events handled on the parent
+ * (or its ancestor) widget handles it (the native focus is set to it).  The
+ * actual focused view is notified by OnFocusChangeInGecko.
+ */
+
+class IMEInputHandler : public TextInputHandlerBase
+{
+public:
+  // TextEventDispatcherListener methods
+  NS_IMETHOD NotifyIME(TextEventDispatcher* aTextEventDispatcher,
+                       const IMENotification& aNotification) override;
+  NS_IMETHOD_(void) OnRemovedFrom(
+                      TextEventDispatcher* aTextEventDispatcher) override;
+  NS_IMETHOD_(void) WillDispatchKeyboardEvent(
+                      TextEventDispatcher* aTextEventDispatcher,
+                      WidgetKeyboardEvent& aKeyboardEvent,
+                      uint32_t aIndexOfKeypress,
+                      void* aData) override;
+
+public:
+  virtual bool OnDestroyWidget(nsChildView* aDestroyingWidget) override;
+
+  virtual void OnFocusChangeInGecko(bool aFocus);
+
+  void OnSelectionChange(const IMENotification& aIMENotification);
+
+  /**
+   * Call [NSTextInputContext handleEvent] for mouse event support of IME
+   */
+  bool OnHandleEvent(NSEvent* aEvent);
+
+  /**
+   * SetMarkedText() is a handler of setMarkedText of NSTextInput.
+   *
+   * @param aAttrString           This mut be an instance of NSAttributedString.
+   *                              If the aString parameter to
+   *                              [ChildView setMarkedText:setSelectedRange:]
+   *                              isn't an instance of NSAttributedString,
+   *                              create an NSAttributedString from it and pass
+   *                              that instead.
+   * @param aSelectedRange        Current selected range (or caret position).
+   * @param aReplacementRange     The range which will be replaced with the
+   *                              aAttrString instead of current marked range.
+   */
+  void SetMarkedText(NSAttributedString* aAttrString,
+                     NSRange& aSelectedRange,
+                     NSRange* aReplacementRange = nullptr);
+
+  /**
+   * GetAttributedSubstringFromRange() returns an NSAttributedString instance
+   * which is allocated as autorelease for aRange.
+   *
+   * @param aRange                The range of string which you want.
+   * @param aActualRange          The actual range of the result.
+   * @return                      The string in aRange.  If the string is empty,
+   *                              this returns nil.  If succeeded, this returns
+   *                              an instance which is allocated as autorelease.
+   *                              If this has some troubles, returns nil.
+   */
+  NSAttributedString* GetAttributedSubstringFromRange(
+                        NSRange& aRange,
+                        NSRange* aActualRange = nullptr);
+
+  /**
+   * SelectedRange() returns current selected range.
+   *
+   * @return                      If an editor has focus, this returns selection
+   *                              range in the editor.  Otherwise, this returns
+   *                              selection range  in the focused document.
+   */
+  NSRange SelectedRange();
+
+  /**
+   * DrawsVerticallyForCharacterAtIndex() returns whether the character at
+   * the given index is being rendered vertically.
+   *
+   * @param aCharIndex            The character offset to query.
+   *
+   * @return                      True if writing-mode is vertical at the given
+   *                              character offset; otherwise false.
+   */
+  bool DrawsVerticallyForCharacterAtIndex(uint32_t aCharIndex);
+
+  /**
+   * FirstRectForCharacterRange() returns first *character* rect in the range.
+   * Cocoa needs the first line rect in the range, but we cannot compute it
+   * on current implementation.
+   *
+   * @param aRange                A range of text to examine.  Its position is
+   *                              an offset from the beginning of the focused
+   *                              editor or document.
+   * @param aActualRange          If this is not null, this returns the actual
+   *                              range used for computing the result.
+   * @return                      An NSRect containing the first character in
+   *                              aRange, in screen coordinates.
+   *                              If the length of aRange is 0, the width will
+   *                              be 0.
+   */
+  NSRect FirstRectForCharacterRange(NSRange& aRange,
+                                    NSRange* aActualRange = nullptr);
+
+  /**
+   * CharacterIndexForPoint() returns an offset of a character at aPoint.
+   * XXX This isn't implemented, always returns 0.
+   *
+   * @param                       The point in screen coordinates.
+   * @return                      The offset of the character at aPoint from
+   *                              the beginning of the focused editor or
+   *                              document.
+   */
+  NSUInteger CharacterIndexForPoint(NSPoint& aPoint);
+
+  /**
+   * GetValidAttributesForMarkedText() returns attributes which we support.
+   *
+   * @return                      Always empty array for now.
+   */
+  NSArray* GetValidAttributesForMarkedText();
+
+  bool HasMarkedText();
+  NSRange MarkedRange();
+
+  bool IsIMEComposing() { return mIsIMEComposing; }
+  bool IsIMEOpened();
+  bool IsIMEEnabled() { return mIsIMEEnabled; }
+  bool IsASCIICapableOnly() { return mIsASCIICapableOnly; }
+  bool IgnoreIMECommit() { return mIgnoreIMECommit; }
+
+  bool IgnoreIMEComposition()
+  {
+    // Ignore the IME composition events when we're pending to discard the
+    // composition and we are not to handle the IME composition now.
+    return (mPendingMethods & kDiscardIMEComposition) &&
+           (mIsInFocusProcessing || !IsFocused());
+  }
+
+  void CommitIMEComposition();
+  void CancelIMEComposition();
+
+  void EnableIME(bool aEnableIME);
+  void SetIMEOpenState(bool aOpen);
+  void SetASCIICapableOnly(bool aASCIICapableOnly);
+
+  /**
+   * True if OSX believes that our view has keyboard focus.
+   */
+  bool IsFocused();
+
+  static CFArrayRef CreateAllIMEModeList();
+  static void DebugPrintAllIMEModes();
+
+  // Don't use ::TSMGetActiveDocument() API directly, the document may not
+  // be what you want.
+  static TSMDocumentID GetCurrentTSMDocumentID();
+
+protected:
+  // We cannot do some jobs in the given stack by some reasons.
+  // Following flags and the timer provide the execution pending mechanism,
+  // See the comment in nsCocoaTextInputHandler.mm.
+  nsCOMPtr<nsITimer> mTimer;
+  enum {
+    kNotifyIMEOfFocusChangeInGecko = 1,
+    kDiscardIMEComposition         = 2,
+    kSyncASCIICapableOnly          = 4
+  };
+  uint32_t mPendingMethods;
+
+  IMEInputHandler(nsChildView* aWidget, NSView<mozView> *aNativeView);
+  virtual ~IMEInputHandler();
+
+  void ResetTimer();
+
+  virtual void ExecutePendingMethods();
+
+  /**
+   * InsertTextAsCommittingComposition() commits current composition.  If there
+   * is no composition, this starts a composition and commits it immediately.
+   *
+   * @param aAttrString           A string which is committed.
+   * @param aReplacementRange     The range which will be replaced with the
+   *                              aAttrString instead of current selection.
+   */
+  void InsertTextAsCommittingComposition(NSAttributedString* aAttrString,
+                                         NSRange* aReplacementRange);
+
+private:
+  // If mIsIMEComposing is true, the composition string is stored here.
+  NSString* mIMECompositionString;
+  // If mIsIMEComposing is true, the start offset of the composition string.
+  uint32_t mIMECompositionStart;
+
+  NSRange mMarkedRange;
+  NSRange mSelectedRange;
+
+  NSRange mRangeForWritingMode; // range within which mWritingMode applies
+  mozilla::WritingMode mWritingMode;
+
+  bool mIsIMEComposing;
+  bool mIsIMEEnabled;
+  bool mIsASCIICapableOnly;
+  bool mIgnoreIMECommit;
+  // This flag is enabled by OnFocusChangeInGecko, and will be cleared by
+  // ExecutePendingMethods.  When this is true, IsFocus() returns TRUE.  At
+  // that time, the focus processing in Gecko might not be finished yet.  So,
+  // you cannot use WidgetQueryContentEvent or something.
+  bool mIsInFocusProcessing;
+  bool mIMEHasFocus;
+
+  void KillIMEComposition();
+  void SendCommittedText(NSString *aString);
+  void OpenSystemPreferredLanguageIME();
+
+  // Pending methods
+  void NotifyIMEOfFocusChangeInGecko();
+  void DiscardIMEComposition();
+  void SyncASCIICapableOnly();
+
+  static bool sStaticMembersInitialized;
+  static CFStringRef sLatestIMEOpenedModeInputSourceID;
+  static void InitStaticMembers();
+  static void OnCurrentTextInputSourceChange(CFNotificationCenterRef aCenter,
+                                             void* aObserver,
+                                             CFStringRef aName,
+                                             const void* aObject,
+                                             CFDictionaryRef aUserInfo);
+
+  static void FlushPendingMethods(nsITimer* aTimer, void* aClosure);
+
+  /**
+   * ConvertToTextRangeStyle converts the given native underline style to
+   * our defined text range type.
+   *
+   * @param aUnderlineStyle       NSUnderlineStyleSingle or
+   *                              NSUnderlineStyleThick.
+   * @param aSelectedRange        Current selected range (or caret position).
+   * @return                      NS_TEXTRANGE_*.
+   */
+  TextRangeType ConvertToTextRangeType(uint32_t aUnderlineStyle,
+                                       NSRange& aSelectedRange);
+
+  /**
+   * GetRangeCount() computes the range count of aAttrString.
+   *
+   * @param aAttrString           An NSAttributedString instance whose number of
+   *                              NSUnderlineStyleAttributeName ranges you with
+   *                              to know.
+   * @return                      The count of NSUnderlineStyleAttributeName
+   *                              ranges in aAttrString.
+   */
+  uint32_t GetRangeCount(NSAttributedString *aString);
+
+  /**
+   * CreateTextRangeArray() returns text ranges for clauses and/or caret.
+   *
+   * @param aAttrString           An NSAttributedString instance which indicates
+   *                              current composition string.
+   * @param aSelectedRange        Current selected range (or caret position).
+   * @return                      The result is set to the
+   *                              NSUnderlineStyleAttributeName ranges in
+   *                              aAttrString.
+   */
+  already_AddRefed<mozilla::TextRangeArray>
+    CreateTextRangeArray(NSAttributedString *aAttrString,
+                         NSRange& aSelectedRange);
+
+  /**
+   * DispatchCompositionStartEvent() dispatches a compositionstart event and
+   * initializes the members indicating composition state.
+   *
+   * @return                      true if it can continues handling composition.
+   *                              Otherwise, e.g., canceled by the web page,
+   *                              this returns false.
+   */
+  bool DispatchCompositionStartEvent();
+
+  /**
+   * DispatchCompositionChangeEvent() dispatches a compositionchange event on
+   * mWidget and modifies the members indicating composition state.
+   *
+   * @param aText                 User text input.
+   * @param aAttrString           An NSAttributedString instance which indicates
+   *                              current composition string.
+   * @param aSelectedRange        Current selected range (or caret position).
+   *
+   * @return                      true if it can continues handling composition.
+   *                              Otherwise, e.g., canceled by the web page,
+   *                              this returns false.
+   */
+  bool DispatchCompositionChangeEvent(const nsString& aText,
+                                      NSAttributedString* aAttrString,
+                                      NSRange& aSelectedRange);
+
+  /**
+   * DispatchCompositionCommitEvent() dispatches a compositioncommit event or
+   * compositioncommitasis event.  If aCommitString is null, dispatches
+   * compositioncommitasis event.  I.e., if aCommitString is null, this
+   * commits the composition with the last data.  Otherwise, commits the
+   * composition with aCommitString value.
+   *
+   * @return                      true if the widget isn't destroyed.
+   *                              Otherwise, false.
+   */
+  bool DispatchCompositionCommitEvent(const nsAString* aCommitString = nullptr);
+
+  // The focused IME handler.  Please note that the handler might lost the
+  // actual focus by deactivating the application.  If we are active, this
+  // must have the actual focused handle.
+  // We cannot access to the NSInputManager during we aren't active, so, the
+  // focused handler can have an IME transaction even if we are deactive.
+  static IMEInputHandler* sFocusedIMEHandler;
+
+  static bool sCachedIsForRTLLangage;
+};
+
+/**
+ * TextInputHandler implements the NSTextInput protocol.
+ */
+class TextInputHandler : public IMEInputHandler
+{
+public:
+  static NSUInteger sLastModifierState;
+
+  static CFArrayRef CreateAllKeyboardLayoutList();
+  static void DebugPrintAllKeyboardLayouts();
+
+  TextInputHandler(nsChildView* aWidget, NSView<mozView> *aNativeView);
+  virtual ~TextInputHandler();
+
+  /**
+   * KeyDown event handler.
+   *
+   * @param aNativeEvent          A native NSKeyDown event.
+   * @return                      TRUE if the event is consumed by web contents
+   *                              or chrome contents.  Otherwise, FALSE.
+   */
+  bool HandleKeyDownEvent(NSEvent* aNativeEvent);
+
+  /**
+   * KeyUp event handler.
+   *
+   * @param aNativeEvent          A native NSKeyUp event.
+   */
+  void HandleKeyUpEvent(NSEvent* aNativeEvent);
+
+  /**
+   * FlagsChanged event handler.
+   *
+   * @param aNativeEvent          A native NSFlagsChanged event.
+   */
+  void HandleFlagsChanged(NSEvent* aNativeEvent);
+
+  /**
+   * Insert the string to content.  I.e., this is a text input event handler.
+   * If this is called during keydown event handling, this may dispatch a
+   * eKeyPress event.  If this is called during composition, this commits
+   * the composition by the aAttrString.
+   *
+   * @param aAttrString           An inserted string.
+   * @param aReplacementRange     The range which will be replaced with the
+   *                              aAttrString instead of current selection.
+   */
+  void InsertText(NSAttributedString *aAttrString,
+                  NSRange* aReplacementRange = nullptr);
+
+  /**
+   * doCommandBySelector event handler.
+   *
+   * @param aSelector             A selector of the command.
+   * @return                      TRUE if the command is consumed.  Otherwise,
+   *                              FALSE.
+   */
+  bool DoCommandBySelector(const char* aSelector);
+
+  /**
+   * KeyPressWasHandled() checks whether keypress event was handled or not.
+   *
+   * @return                      TRUE if keypress event for latest native key
+   *                              event was handled.  Otherwise, FALSE.
+   *                              If this handler isn't handling any key events,
+   *                              always returns FALSE.
+   */
+  bool KeyPressWasHandled()
+  {
+    KeyEventState* currentKeyEvent = GetCurrentKeyEvent();
+    return currentKeyEvent && currentKeyEvent->mKeyPressHandled;
+  }
+
+protected:
+  // Stores the association of device dependent modifier flags with a modifier
+  // keyCode.  Being device dependent, this association may differ from one kind
+  // of hardware to the next.
+  struct ModifierKey
+  {
+    NSUInteger flags;
+    unsigned short keyCode;
+
+    ModifierKey(NSUInteger aFlags, unsigned short aKeyCode) :
+      flags(aFlags), keyCode(aKeyCode)
+    {
+    }
+
+    NSUInteger GetDeviceDependentFlags() const
+    {
+      return (flags & ~NSDeviceIndependentModifierFlagsMask);
+    }
+
+    NSUInteger GetDeviceIndependentFlags() const
+    {
+      return (flags & NSDeviceIndependentModifierFlagsMask);
+    }
+  };
+  typedef nsTArray<ModifierKey> ModifierKeyArray;
+  ModifierKeyArray mModifierKeys;
+
+  /**
+   * GetModifierKeyForNativeKeyCode() returns the stored ModifierKey for
+   * the key.
+   */
+  const ModifierKey*
+    GetModifierKeyForNativeKeyCode(unsigned short aKeyCode) const;
+
+  /**
+   * GetModifierKeyForDeviceDependentFlags() returns the stored ModifierKey for
+   * the device dependent flags.
+   */
+  const ModifierKey*
+    GetModifierKeyForDeviceDependentFlags(NSUInteger aFlags) const;
+
+  /**
+   * DispatchKeyEventForFlagsChanged() dispatches keydown event or keyup event
+   * for the aNativeEvent.
+   *
+   * @param aNativeEvent          A native flagschanged event which you want to
+   *                              dispatch our key event for.
+   * @param aDispatchKeyDown      TRUE if you want to dispatch a keydown event.
+   *                              Otherwise, i.e., to dispatch keyup event,
+   *                              FALSE.
+   */
+  void DispatchKeyEventForFlagsChanged(NSEvent* aNativeEvent,
+                                       bool aDispatchKeyDown);
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif // TextInputHandler_h_
diff --git a/widget/cocoa/TextInputHandler.mm b/widget/cocoa/TextInputHandler.mm
new file mode 100644
index 0000000000..348d99ab69
--- /dev/null
+++ b/widget/cocoa/TextInputHandler.mm
@@ -0,0 +1,4533 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "TextInputHandler.h"
+
+#include "mozilla/Logging.h"
+
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/AutoRestore.h"
+#include "mozilla/MiscEvents.h"
+#include "mozilla/MouseEvents.h"
+#include "mozilla/TextEventDispatcher.h"
+#include "mozilla/TextEvents.h"
+
+#include "nsChildView.h"
+#include "nsObjCExceptions.h"
+#include "nsBidiUtils.h"
+#include "nsToolkit.h"
+#include "nsCocoaUtils.h"
+#include "WidgetUtils.h"
+#include "nsPrintfCString.h"
+#include "ComplexTextInputPanel.h"
+
+using namespace mozilla;
+using namespace mozilla::widget;
+
+LazyLogModule gLog("TextInputHandlerWidgets");
+
+static const char*
+OnOrOff(bool aBool)
+{
+  return aBool ? "ON" : "off";
+}
+
+static const char*
+TrueOrFalse(bool aBool)
+{
+  return aBool ? "TRUE" : "FALSE";
+}
+
+static const char*
+GetKeyNameForNativeKeyCode(unsigned short aNativeKeyCode)
+{
+  switch (aNativeKeyCode) {
+    case kVK_Escape:              return "Escape";
+    case kVK_RightCommand:        return "Right-Command";
+    case kVK_Command:             return "Command";
+    case kVK_Shift:               return "Shift";
+    case kVK_CapsLock:            return "CapsLock";
+    case kVK_Option:              return "Option";
+    case kVK_Control:             return "Control";
+    case kVK_RightShift:          return "Right-Shift";
+    case kVK_RightOption:         return "Right-Option";
+    case kVK_RightControl:        return "Right-Control";
+    case kVK_ANSI_KeypadClear:    return "Clear";
+
+    case kVK_F1:                  return "F1";
+    case kVK_F2:                  return "F2";
+    case kVK_F3:                  return "F3";
+    case kVK_F4:                  return "F4";
+    case kVK_F5:                  return "F5";
+    case kVK_F6:                  return "F6";
+    case kVK_F7:                  return "F7";
+    case kVK_F8:                  return "F8";
+    case kVK_F9:                  return "F9";
+    case kVK_F10:                 return "F10";
+    case kVK_F11:                 return "F11";
+    case kVK_F12:                 return "F12";
+    case kVK_F13:                 return "F13/PrintScreen";
+    case kVK_F14:                 return "F14/ScrollLock";
+    case kVK_F15:                 return "F15/Pause";
+
+    case kVK_ANSI_Keypad0:        return "NumPad-0";
+    case kVK_ANSI_Keypad1:        return "NumPad-1";
+    case kVK_ANSI_Keypad2:        return "NumPad-2";
+    case kVK_ANSI_Keypad3:        return "NumPad-3";
+    case kVK_ANSI_Keypad4:        return "NumPad-4";
+    case kVK_ANSI_Keypad5:        return "NumPad-5";
+    case kVK_ANSI_Keypad6:        return "NumPad-6";
+    case kVK_ANSI_Keypad7:        return "NumPad-7";
+    case kVK_ANSI_Keypad8:        return "NumPad-8";
+    case kVK_ANSI_Keypad9:        return "NumPad-9";
+
+    case kVK_ANSI_KeypadMultiply: return "NumPad-*";
+    case kVK_ANSI_KeypadPlus:     return "NumPad-+";
+    case kVK_ANSI_KeypadMinus:    return "NumPad--";
+    case kVK_ANSI_KeypadDecimal:  return "NumPad-.";
+    case kVK_ANSI_KeypadDivide:   return "NumPad-/";
+    case kVK_ANSI_KeypadEquals:   return "NumPad-=";
+    case kVK_ANSI_KeypadEnter:    return "NumPad-Enter";
+    case kVK_Return:              return "Return";
+    case kVK_Powerbook_KeypadEnter: return "NumPad-EnterOnPowerBook";
+
+    case kVK_PC_Insert:           return "Insert/Help";
+    case kVK_PC_Delete:           return "Delete";
+    case kVK_Tab:                 return "Tab";
+    case kVK_PC_Backspace:        return "Backspace";
+    case kVK_Home:                return "Home";
+    case kVK_End:                 return "End";
+    case kVK_PageUp:              return "PageUp";
+    case kVK_PageDown:            return "PageDown";
+    case kVK_LeftArrow:           return "LeftArrow";
+    case kVK_RightArrow:          return "RightArrow";
+    case kVK_UpArrow:             return "UpArrow";
+    case kVK_DownArrow:           return "DownArrow";
+    case kVK_PC_ContextMenu:      return "ContextMenu";
+
+    case kVK_Function:            return "Function";
+    case kVK_VolumeUp:            return "VolumeUp";
+    case kVK_VolumeDown:          return "VolumeDown";
+    case kVK_Mute:                return "Mute";
+
+    case kVK_ISO_Section:         return "ISO_Section";
+
+    case kVK_JIS_Yen:             return "JIS_Yen";
+    case kVK_JIS_Underscore:      return "JIS_Underscore";
+    case kVK_JIS_KeypadComma:     return "JIS_KeypadComma";
+    case kVK_JIS_Eisu:            return "JIS_Eisu";
+    case kVK_JIS_Kana:            return "JIS_Kana";
+
+    case kVK_ANSI_A:              return "A";
+    case kVK_ANSI_B:              return "B";
+    case kVK_ANSI_C:              return "C";
+    case kVK_ANSI_D:              return "D";
+    case kVK_ANSI_E:              return "E";
+    case kVK_ANSI_F:              return "F";
+    case kVK_ANSI_G:              return "G";
+    case kVK_ANSI_H:              return "H";
+    case kVK_ANSI_I:              return "I";
+    case kVK_ANSI_J:              return "J";
+    case kVK_ANSI_K:              return "K";
+    case kVK_ANSI_L:              return "L";
+    case kVK_ANSI_M:              return "M";
+    case kVK_ANSI_N:              return "N";
+    case kVK_ANSI_O:              return "O";
+    case kVK_ANSI_P:              return "P";
+    case kVK_ANSI_Q:              return "Q";
+    case kVK_ANSI_R:              return "R";
+    case kVK_ANSI_S:              return "S";
+    case kVK_ANSI_T:              return "T";
+    case kVK_ANSI_U:              return "U";
+    case kVK_ANSI_V:              return "V";
+    case kVK_ANSI_W:              return "W";
+    case kVK_ANSI_X:              return "X";
+    case kVK_ANSI_Y:              return "Y";
+    case kVK_ANSI_Z:              return "Z";
+
+    case kVK_ANSI_1:              return "1";
+    case kVK_ANSI_2:              return "2";
+    case kVK_ANSI_3:              return "3";
+    case kVK_ANSI_4:              return "4";
+    case kVK_ANSI_5:              return "5";
+    case kVK_ANSI_6:              return "6";
+    case kVK_ANSI_7:              return "7";
+    case kVK_ANSI_8:              return "8";
+    case kVK_ANSI_9:              return "9";
+    case kVK_ANSI_0:              return "0";
+    case kVK_ANSI_Equal:          return "Equal";
+    case kVK_ANSI_Minus:          return "Minus";
+    case kVK_ANSI_RightBracket:   return "RightBracket";
+    case kVK_ANSI_LeftBracket:    return "LeftBracket";
+    case kVK_ANSI_Quote:          return "Quote";
+    case kVK_ANSI_Semicolon:      return "Semicolon";
+    case kVK_ANSI_Backslash:      return "Backslash";
+    case kVK_ANSI_Comma:          return "Comma";
+    case kVK_ANSI_Slash:          return "Slash";
+    case kVK_ANSI_Period:         return "Period";
+    case kVK_ANSI_Grave:          return "Grave";
+
+    default:                      return "undefined";
+  }
+}
+
+static const char*
+GetCharacters(const NSString* aString)
+{
+  nsAutoString str;
+  nsCocoaUtils::GetStringForNSString(aString, str);
+  if (str.IsEmpty()) {
+    return "";
+  }
+
+  nsAutoString escapedStr;
+  for (uint32_t i = 0; i < str.Length(); i++) {
+    char16_t ch = str[i];
+    if (ch < 0x20) {
+      nsPrintfCString utf8str("(U+%04X)", ch);
+      escapedStr += NS_ConvertUTF8toUTF16(utf8str);
+    } else if (ch <= 0x7E) {
+      escapedStr += ch;
+    } else {
+      nsPrintfCString utf8str("(U+%04X)", ch);
+      escapedStr += ch;
+      escapedStr += NS_ConvertUTF8toUTF16(utf8str);
+    }
+  }
+
+  // the result will be freed automatically by cocoa.
+  NSString* result = nsCocoaUtils::ToNSString(escapedStr);
+  return [result UTF8String];
+}
+
+static const char*
+GetCharacters(const CFStringRef aString)
+{
+  const NSString* str = reinterpret_cast<const NSString*>(aString);
+  return GetCharacters(str);
+}
+
+static const char*
+GetNativeKeyEventType(NSEvent* aNativeEvent)
+{
+  switch ([aNativeEvent type]) {
+    case NSKeyDown:      return "NSKeyDown";
+    case NSKeyUp:        return "NSKeyUp";
+    case NSFlagsChanged: return "NSFlagsChanged";
+    default:             return "not key event";
+  }
+}
+
+static const char*
+GetGeckoKeyEventType(const WidgetEvent& aEvent)
+{
+  switch (aEvent.mMessage) {
+    case eKeyDown:       return "eKeyDown";
+    case eKeyUp:         return "eKeyUp";
+    case eKeyPress:      return "eKeyPress";
+    default:             return "not key event";
+  }
+}
+
+static const char*
+GetWindowLevelName(NSInteger aWindowLevel)
+{
+  switch (aWindowLevel) {
+    case kCGBaseWindowLevelKey:
+      return "kCGBaseWindowLevelKey (NSNormalWindowLevel)";
+    case kCGMinimumWindowLevelKey:
+      return "kCGMinimumWindowLevelKey";
+    case kCGDesktopWindowLevelKey:
+      return "kCGDesktopWindowLevelKey";
+    case kCGBackstopMenuLevelKey:
+      return "kCGBackstopMenuLevelKey";
+    case kCGNormalWindowLevelKey:
+      return "kCGNormalWindowLevelKey";
+    case kCGFloatingWindowLevelKey:
+      return "kCGFloatingWindowLevelKey (NSFloatingWindowLevel)";
+    case kCGTornOffMenuWindowLevelKey:
+      return "kCGTornOffMenuWindowLevelKey (NSSubmenuWindowLevel, NSTornOffMenuWindowLevel)";
+    case kCGDockWindowLevelKey:
+      return "kCGDockWindowLevelKey (NSDockWindowLevel)";
+    case kCGMainMenuWindowLevelKey:
+      return "kCGMainMenuWindowLevelKey (NSMainMenuWindowLevel)";
+    case kCGStatusWindowLevelKey:
+      return "kCGStatusWindowLevelKey (NSStatusWindowLevel)";
+    case kCGModalPanelWindowLevelKey:
+      return "kCGModalPanelWindowLevelKey (NSModalPanelWindowLevel)";
+    case kCGPopUpMenuWindowLevelKey:
+      return "kCGPopUpMenuWindowLevelKey (NSPopUpMenuWindowLevel)";
+    case kCGDraggingWindowLevelKey:
+      return "kCGDraggingWindowLevelKey";
+    case kCGScreenSaverWindowLevelKey:
+      return "kCGScreenSaverWindowLevelKey (NSScreenSaverWindowLevel)";
+    case kCGMaximumWindowLevelKey:
+      return "kCGMaximumWindowLevelKey";
+    case kCGOverlayWindowLevelKey:
+      return "kCGOverlayWindowLevelKey";
+    case kCGHelpWindowLevelKey:
+      return "kCGHelpWindowLevelKey";
+    case kCGUtilityWindowLevelKey:
+      return "kCGUtilityWindowLevelKey";
+    case kCGDesktopIconWindowLevelKey:
+      return "kCGDesktopIconWindowLevelKey";
+    case kCGCursorWindowLevelKey:
+      return "kCGCursorWindowLevelKey";
+    case kCGNumberOfWindowLevelKeys:
+      return "kCGNumberOfWindowLevelKeys";
+    default:
+      return "unknown window level";
+  }
+}
+
+static bool
+IsControlChar(uint32_t aCharCode)
+{
+  return aCharCode < ' ' || aCharCode == 0x7F;
+}
+
+static uint32_t gHandlerInstanceCount = 0;
+
+static void
+EnsureToLogAllKeyboardLayoutsAndIMEs()
+{
+  static bool sDone = false;
+  if (!sDone) {
+    sDone = true;
+    TextInputHandler::DebugPrintAllKeyboardLayouts();
+    IMEInputHandler::DebugPrintAllIMEModes();
+  }
+}
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  TISInputSourceWrapper implementation
+ *
+ ******************************************************************************/
+
+TISInputSourceWrapper* TISInputSourceWrapper::sCurrentInputSource = nullptr;
+
+// static
+TISInputSourceWrapper&
+TISInputSourceWrapper::CurrentInputSource()
+{
+  if (!sCurrentInputSource) {
+    sCurrentInputSource = new TISInputSourceWrapper();
+  }
+  if (!sCurrentInputSource->IsInitializedByCurrentInputSource()) {
+    sCurrentInputSource->InitByCurrentInputSource();
+  }
+  return *sCurrentInputSource;
+}
+
+// static
+void
+TISInputSourceWrapper::Shutdown()
+{
+  if (!sCurrentInputSource) {
+    return;
+  }
+  sCurrentInputSource->Clear();
+  delete sCurrentInputSource;
+  sCurrentInputSource = nullptr;
+}
+
+bool
+TISInputSourceWrapper::TranslateToString(UInt32 aKeyCode, UInt32 aModifiers,
+                                         UInt32 aKbType, nsAString &aStr)
+{
+  aStr.Truncate();
+
+  const UCKeyboardLayout* UCKey = GetUCKeyboardLayout();
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::TranslateToString, aKeyCode=0x%X, "
+     "aModifiers=0x%X, aKbType=0x%X UCKey=%p\n    "
+     "Shift: %s, Ctrl: %s, Opt: %s, Cmd: %s, CapsLock: %s, NumLock: %s",
+     this, aKeyCode, aModifiers, aKbType, UCKey,
+     OnOrOff(aModifiers & shiftKey), OnOrOff(aModifiers & controlKey),
+     OnOrOff(aModifiers & optionKey), OnOrOff(aModifiers & cmdKey),
+     OnOrOff(aModifiers & alphaLock),
+     OnOrOff(aModifiers & kEventKeyModifierNumLockMask)));
+
+  NS_ENSURE_TRUE(UCKey, false);
+
+  UInt32 deadKeyState = 0;
+  UniCharCount len;
+  UniChar chars[5];
+  OSStatus err = ::UCKeyTranslate(UCKey, aKeyCode,
+                                  kUCKeyActionDown, aModifiers >> 8,
+                                  aKbType, kUCKeyTranslateNoDeadKeysMask,
+                                  &deadKeyState, 5, &len, chars);
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::TranslateToString, err=0x%X, len=%llu",
+     this, err, len));
+
+  NS_ENSURE_TRUE(err == noErr, false);
+  if (len == 0) {
+    return true;
+  }
+  NS_ENSURE_TRUE(EnsureStringLength(aStr, len), false);
+  NS_ASSERTION(sizeof(char16_t) == sizeof(UniChar),
+               "size of char16_t and size of UniChar are different");
+  memcpy(aStr.BeginWriting(), chars, len * sizeof(char16_t));
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::TranslateToString, aStr=\"%s\"",
+     this, NS_ConvertUTF16toUTF8(aStr).get()));
+
+  return true;
+}
+
+uint32_t
+TISInputSourceWrapper::TranslateToChar(UInt32 aKeyCode, UInt32 aModifiers,
+                                       UInt32 aKbType)
+{
+  nsAutoString str;
+  if (!TranslateToString(aKeyCode, aModifiers, aKbType, str) ||
+      str.Length() != 1) {
+    return 0;
+  }
+  return static_cast<uint32_t>(str.CharAt(0));
+}
+
+void
+TISInputSourceWrapper::InitByInputSourceID(const char* aID)
+{
+  Clear();
+  if (!aID)
+    return;
+
+  CFStringRef idstr = ::CFStringCreateWithCString(kCFAllocatorDefault, aID,
+                                                  kCFStringEncodingASCII);
+  InitByInputSourceID(idstr);
+  ::CFRelease(idstr);
+}
+
+void
+TISInputSourceWrapper::InitByInputSourceID(const nsAFlatString &aID)
+{
+  Clear();
+  if (aID.IsEmpty())
+    return;
+  CFStringRef idstr = ::CFStringCreateWithCharacters(kCFAllocatorDefault,
+                                                     reinterpret_cast<const UniChar*>(aID.get()),
+                                                     aID.Length());
+  InitByInputSourceID(idstr);
+  ::CFRelease(idstr);
+}
+
+void
+TISInputSourceWrapper::InitByInputSourceID(const CFStringRef aID)
+{
+  Clear();
+  if (!aID)
+    return;
+  const void* keys[] = { kTISPropertyInputSourceID };
+  const void* values[] = { aID };
+  CFDictionaryRef filter =
+  ::CFDictionaryCreate(kCFAllocatorDefault, keys, values, 1, NULL, NULL);
+  NS_ASSERTION(filter, "failed to create the filter");
+  mInputSourceList = ::TISCreateInputSourceList(filter, true);
+  ::CFRelease(filter);
+  if (::CFArrayGetCount(mInputSourceList) > 0) {
+    mInputSource = static_cast<TISInputSourceRef>(
+      const_cast<void *>(::CFArrayGetValueAtIndex(mInputSourceList, 0)));
+    if (IsKeyboardLayout()) {
+      mKeyboardLayout = mInputSource;
+    }
+  }
+}
+
+void
+TISInputSourceWrapper::InitByLayoutID(SInt32 aLayoutID,
+                                      bool aOverrideKeyboard)
+{
+  // NOTE: Doument new layout IDs in TextInputHandler.h when you add ones.
+  switch (aLayoutID) {
+    case 0:
+      InitByInputSourceID("com.apple.keylayout.US");
+      break;
+    case 1:
+      InitByInputSourceID("com.apple.keylayout.Greek");
+      break;
+    case 2:
+      InitByInputSourceID("com.apple.keylayout.German");
+      break;
+    case 3:
+      InitByInputSourceID("com.apple.keylayout.Swedish-Pro");
+      break;
+    case 4:
+      InitByInputSourceID("com.apple.keylayout.DVORAK-QWERTYCMD");
+      break;
+    case 5:
+      InitByInputSourceID("com.apple.keylayout.Thai");
+      break;
+    case 6:
+      InitByInputSourceID("com.apple.keylayout.Arabic");
+      break;
+    case 7:
+      InitByInputSourceID("com.apple.keylayout.ArabicPC");
+      break;
+    case 8:
+      InitByInputSourceID("com.apple.keylayout.French");
+      break;
+    case 9:
+      InitByInputSourceID("com.apple.keylayout.Hebrew");
+      break;
+    case 10:
+      InitByInputSourceID("com.apple.keylayout.Lithuanian");
+      break;
+    case 11:
+      InitByInputSourceID("com.apple.keylayout.Norwegian");
+      break;
+    case 12:
+      InitByInputSourceID("com.apple.keylayout.Spanish");
+      break;
+    default:
+      Clear();
+      break;
+  }
+  mOverrideKeyboard = aOverrideKeyboard;
+}
+
+void
+TISInputSourceWrapper::InitByCurrentInputSource()
+{
+  Clear();
+  mInputSource = ::TISCopyCurrentKeyboardInputSource();
+  mKeyboardLayout = ::TISCopyInputMethodKeyboardLayoutOverride();
+  if (!mKeyboardLayout) {
+    mKeyboardLayout = ::TISCopyCurrentKeyboardLayoutInputSource();
+  }
+  // If this causes composition, the current keyboard layout may input non-ASCII
+  // characters such as Japanese Kana characters or Hangul characters.
+  // However, we need to set ASCII characters to DOM key events for consistency
+  // with other platforms.
+  if (IsOpenedIMEMode()) {
+    TISInputSourceWrapper tis(mKeyboardLayout);
+    if (!tis.IsASCIICapable()) {
+      mKeyboardLayout =
+        ::TISCopyCurrentASCIICapableKeyboardLayoutInputSource();
+    }
+  }
+}
+
+void
+TISInputSourceWrapper::InitByCurrentKeyboardLayout()
+{
+  Clear();
+  mInputSource = ::TISCopyCurrentKeyboardLayoutInputSource();
+  mKeyboardLayout = mInputSource;
+}
+
+void
+TISInputSourceWrapper::InitByCurrentASCIICapableInputSource()
+{
+  Clear();
+  mInputSource = ::TISCopyCurrentASCIICapableKeyboardInputSource();
+  mKeyboardLayout = ::TISCopyInputMethodKeyboardLayoutOverride();
+  if (mKeyboardLayout) {
+    TISInputSourceWrapper tis(mKeyboardLayout);
+    if (!tis.IsASCIICapable()) {
+      mKeyboardLayout = nullptr;
+    }
+  }
+  if (!mKeyboardLayout) {
+    mKeyboardLayout =
+      ::TISCopyCurrentASCIICapableKeyboardLayoutInputSource();
+  }
+}
+
+void
+TISInputSourceWrapper::InitByCurrentASCIICapableKeyboardLayout()
+{
+  Clear();
+  mInputSource = ::TISCopyCurrentASCIICapableKeyboardLayoutInputSource();
+  mKeyboardLayout = mInputSource;
+}
+
+void
+TISInputSourceWrapper::InitByCurrentInputMethodKeyboardLayoutOverride()
+{
+  Clear();
+  mInputSource = ::TISCopyInputMethodKeyboardLayoutOverride();
+  mKeyboardLayout = mInputSource;
+}
+
+void
+TISInputSourceWrapper::InitByTISInputSourceRef(TISInputSourceRef aInputSource)
+{
+  Clear();
+  mInputSource = aInputSource;
+  if (IsKeyboardLayout()) {
+    mKeyboardLayout = mInputSource;
+  }
+}
+
+void
+TISInputSourceWrapper::InitByLanguage(CFStringRef aLanguage)
+{
+  Clear();
+  mInputSource = ::TISCopyInputSourceForLanguage(aLanguage);
+  if (IsKeyboardLayout()) {
+    mKeyboardLayout = mInputSource;
+  }
+}
+
+const UCKeyboardLayout*
+TISInputSourceWrapper::GetUCKeyboardLayout()
+{
+  NS_ENSURE_TRUE(mKeyboardLayout, nullptr);
+  if (mUCKeyboardLayout) {
+    return mUCKeyboardLayout;
+  }
+  CFDataRef uchr = static_cast<CFDataRef>(
+    ::TISGetInputSourceProperty(mKeyboardLayout,
+                                kTISPropertyUnicodeKeyLayoutData));
+
+  // We should be always able to get the layout here.
+  NS_ENSURE_TRUE(uchr, nullptr);
+  mUCKeyboardLayout =
+    reinterpret_cast<const UCKeyboardLayout*>(CFDataGetBytePtr(uchr));
+  return mUCKeyboardLayout;
+}
+
+bool
+TISInputSourceWrapper::GetBoolProperty(const CFStringRef aKey)
+{
+  CFBooleanRef ret = static_cast<CFBooleanRef>(
+    ::TISGetInputSourceProperty(mInputSource, aKey));
+  return ::CFBooleanGetValue(ret);
+}
+
+bool
+TISInputSourceWrapper::GetStringProperty(const CFStringRef aKey,
+                                         CFStringRef &aStr)
+{
+  aStr = static_cast<CFStringRef>(
+    ::TISGetInputSourceProperty(mInputSource, aKey));
+  return aStr != nullptr;
+}
+
+bool
+TISInputSourceWrapper::GetStringProperty(const CFStringRef aKey,
+                                         nsAString &aStr)
+{
+  CFStringRef str;
+  GetStringProperty(aKey, str);
+  nsCocoaUtils::GetStringForNSString((const NSString*)str, aStr);
+  return !aStr.IsEmpty();
+}
+
+bool
+TISInputSourceWrapper::IsOpenedIMEMode()
+{
+  NS_ENSURE_TRUE(mInputSource, false);
+  if (!IsIMEMode())
+    return false;
+  return !IsASCIICapable();
+}
+
+bool
+TISInputSourceWrapper::IsIMEMode()
+{
+  NS_ENSURE_TRUE(mInputSource, false);
+  CFStringRef str;
+  GetInputSourceType(str);
+  NS_ENSURE_TRUE(str, false);
+  return ::CFStringCompare(kTISTypeKeyboardInputMode,
+                           str, 0) == kCFCompareEqualTo;
+}
+
+bool
+TISInputSourceWrapper::IsKeyboardLayout()
+{
+  NS_ENSURE_TRUE(mInputSource, false);
+  CFStringRef str;
+  GetInputSourceType(str);
+  NS_ENSURE_TRUE(str, false);
+  return ::CFStringCompare(kTISTypeKeyboardLayout,
+                           str, 0) == kCFCompareEqualTo;
+}
+
+bool
+TISInputSourceWrapper::GetLanguageList(CFArrayRef &aLanguageList)
+{
+  NS_ENSURE_TRUE(mInputSource, false);
+  aLanguageList = static_cast<CFArrayRef>(
+    ::TISGetInputSourceProperty(mInputSource,
+                                kTISPropertyInputSourceLanguages));
+  return aLanguageList != nullptr;
+}
+
+bool
+TISInputSourceWrapper::GetPrimaryLanguage(CFStringRef &aPrimaryLanguage)
+{
+  NS_ENSURE_TRUE(mInputSource, false);
+  CFArrayRef langList;
+  NS_ENSURE_TRUE(GetLanguageList(langList), false);
+  if (::CFArrayGetCount(langList) == 0)
+    return false;
+  aPrimaryLanguage =
+    static_cast<CFStringRef>(::CFArrayGetValueAtIndex(langList, 0));
+  return aPrimaryLanguage != nullptr;
+}
+
+bool
+TISInputSourceWrapper::GetPrimaryLanguage(nsAString &aPrimaryLanguage)
+{
+  NS_ENSURE_TRUE(mInputSource, false);
+  CFStringRef primaryLanguage;
+  NS_ENSURE_TRUE(GetPrimaryLanguage(primaryLanguage), false);
+  nsCocoaUtils::GetStringForNSString((const NSString*)primaryLanguage,
+                                     aPrimaryLanguage);
+  return !aPrimaryLanguage.IsEmpty();
+}
+
+bool
+TISInputSourceWrapper::IsForRTLLanguage()
+{
+  if (mIsRTL < 0) {
+    // Get the input character of the 'A' key of ANSI keyboard layout.
+    nsAutoString str;
+    bool ret = TranslateToString(kVK_ANSI_A, 0, eKbdType_ANSI, str);
+    NS_ENSURE_TRUE(ret, ret);
+    char16_t ch = str.IsEmpty() ? char16_t(0) : str.CharAt(0);
+    mIsRTL = UCS2_CHAR_IS_BIDI(ch);
+  }
+  return mIsRTL != 0;
+}
+
+bool
+TISInputSourceWrapper::IsInitializedByCurrentInputSource()
+{
+  return mInputSource == ::TISCopyCurrentKeyboardInputSource();
+}
+
+void
+TISInputSourceWrapper::Select()
+{
+  if (!mInputSource)
+    return;
+  ::TISSelectInputSource(mInputSource);
+}
+
+void
+TISInputSourceWrapper::Clear()
+{
+  // Clear() is always called when TISInputSourceWrappper is created.
+  EnsureToLogAllKeyboardLayoutsAndIMEs();
+
+  if (mInputSourceList) {
+    ::CFRelease(mInputSourceList);
+  }
+  mInputSourceList = nullptr;
+  mInputSource = nullptr;
+  mKeyboardLayout = nullptr;
+  mIsRTL = -1;
+  mUCKeyboardLayout = nullptr;
+  mOverrideKeyboard = false;
+}
+
+bool
+TISInputSourceWrapper::IsPrintableKeyEvent(NSEvent* aNativeKeyEvent) const
+{
+  UInt32 nativeKeyCode = [aNativeKeyEvent keyCode];
+
+  bool isPrintableKey = !TextInputHandler::IsSpecialGeckoKey(nativeKeyCode);
+  if (isPrintableKey &&
+      [aNativeKeyEvent type] != NSKeyDown &&
+      [aNativeKeyEvent type] != NSKeyUp) {
+    NS_WARNING("Why the printable key doesn't cause NSKeyDown or NSKeyUp?");
+    isPrintableKey = false;
+  }
+  return isPrintableKey;
+}
+
+UInt32
+TISInputSourceWrapper::GetKbdType() const
+{
+  // If a keyboard layout override is set, we also need to force the keyboard
+  // type to something ANSI to avoid test failures on machines with JIS
+  // keyboards (since the pair of keyboard layout and physical keyboard type
+  // form the actual key layout).  This assumes that the test setting the
+  // override was written assuming an ANSI keyboard.
+  return mOverrideKeyboard ? eKbdType_ANSI : ::LMGetKbdType();
+}
+
+void
+TISInputSourceWrapper::ComputeInsertStringForCharCode(
+                         NSEvent* aNativeKeyEvent,
+                         const WidgetKeyboardEvent& aKeyEvent,
+                         const nsAString* aInsertString,
+                         nsAString& aResult)
+{
+  if (aInsertString) {
+    // If the caller expects that the aInsertString will be input, we shouldn't
+    // change it.
+    aResult = *aInsertString;
+  } else if (IsPrintableKeyEvent(aNativeKeyEvent)) {
+    // If IME is open, [aNativeKeyEvent characters] may be a character
+    // which will be appended to the composition string.  However, especially,
+    // while IME is disabled, most users and developers expect the key event
+    // works as IME closed.  So, we should compute the aResult with
+    // the ASCII capable keyboard layout.
+    // NOTE: Such keyboard layouts typically change the layout to its ASCII
+    //       capable layout when Command key is pressed.  And we don't worry
+    //       when Control key is pressed too because it causes inputting
+    //       control characters.
+    // Additionally, if the key event doesn't input any text, the event may be
+    // dead key event.  In this case, the charCode value should be the dead
+    // character.
+    UInt32 nativeKeyCode = [aNativeKeyEvent keyCode];
+    if ((!aKeyEvent.IsMeta() && !aKeyEvent.IsControl() && IsOpenedIMEMode()) ||
+        ![[aNativeKeyEvent characters] length]) {
+      UInt32 state =
+        nsCocoaUtils::ConvertToCarbonModifier([aNativeKeyEvent modifierFlags]);
+      uint32_t ch = TranslateToChar(nativeKeyCode, state, GetKbdType());
+      if (ch) {
+        aResult = ch;
+      }
+    } else {
+      // If the caller isn't sure what string will be input, let's use
+      // characters of NSEvent.
+      nsCocoaUtils::GetStringForNSString([aNativeKeyEvent characters], aResult);
+    }
+
+    // If control key is pressed and the eventChars is a non-printable control
+    // character, we should convert it to ASCII alphabet.
+    if (aKeyEvent.IsControl() &&
+        !aResult.IsEmpty() && aResult[0] <= char16_t(26)) {
+      aResult = (aKeyEvent.IsShift() ^ aKeyEvent.IsCapsLocked()) ?
+        static_cast<char16_t>(aResult[0] + ('A' - 1)) :
+        static_cast<char16_t>(aResult[0] + ('a' - 1));
+    }
+    // If Meta key is pressed, it may cause to switch the keyboard layout like
+    // Arabic, Russian, Hebrew, Greek and Dvorak-QWERTY.
+    else if (aKeyEvent.IsMeta() &&
+             !(aKeyEvent.IsControl() || aKeyEvent.IsAlt())) {
+      UInt32 kbType = GetKbdType();
+      UInt32 numLockState =
+        aKeyEvent.IsNumLocked() ? kEventKeyModifierNumLockMask : 0;
+      UInt32 capsLockState = aKeyEvent.IsCapsLocked() ? alphaLock : 0;
+      UInt32 shiftState = aKeyEvent.IsShift() ? shiftKey : 0;
+      uint32_t uncmdedChar =
+        TranslateToChar(nativeKeyCode, numLockState, kbType);
+      uint32_t cmdedChar =
+        TranslateToChar(nativeKeyCode, cmdKey | numLockState, kbType);
+      // If we can make a good guess at the characters that the user would
+      // expect this key combination to produce (with and without Shift) then
+      // use those characters.  This also corrects for CapsLock.
+      uint32_t ch = 0;
+      if (uncmdedChar == cmdedChar) {
+        // The characters produced with Command seem similar to those without
+        // Command.
+        ch = TranslateToChar(nativeKeyCode,
+                             shiftState | capsLockState | numLockState, kbType);
+      } else {
+        TISInputSourceWrapper USLayout("com.apple.keylayout.US");
+        uint32_t uncmdedUSChar =
+          USLayout.TranslateToChar(nativeKeyCode, numLockState, kbType);
+        // If it looks like characters from US keyboard layout when Command key
+        // is pressed, we should compute a character in the layout.
+        if (uncmdedUSChar == cmdedChar) {
+          ch = USLayout.TranslateToChar(nativeKeyCode,
+                          shiftState | capsLockState | numLockState, kbType);
+        }
+      }
+
+      // If there is a more preferred character for the commanded key event,
+      // we should use it.
+      if (ch) {
+        aResult = ch;
+      }
+    }
+  }
+
+  // Remove control characters which shouldn't be inputted on editor.
+  // XXX Currently, we don't find any cases inserting control characters with
+  //     printable character.  So, just checking first character is enough.
+  if (!aResult.IsEmpty() && IsControlChar(aResult[0])) {
+    aResult.Truncate();
+  }
+}
+
+void
+TISInputSourceWrapper::InitKeyEvent(NSEvent *aNativeKeyEvent,
+                                    WidgetKeyboardEvent& aKeyEvent,
+                                    const nsAString *aInsertString)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::InitKeyEvent, aNativeKeyEvent=%p, "
+     "aKeyEvent.mMessage=%s, aInsertString=%p, IsOpenedIMEMode()=%s",
+     this, aNativeKeyEvent, GetGeckoKeyEventType(aKeyEvent), aInsertString,
+     TrueOrFalse(IsOpenedIMEMode())));
+
+  NS_ENSURE_TRUE(aNativeKeyEvent, );
+
+  nsCocoaUtils::InitInputEvent(aKeyEvent, aNativeKeyEvent);
+
+  // This is used only while dispatching the event (which is a synchronous
+  // call), so there is no need to retain and release this data.
+  aKeyEvent.mNativeKeyEvent = aNativeKeyEvent;
+
+  // Fill in fields used for Cocoa NPAPI plugins
+  if ([aNativeKeyEvent type] == NSKeyDown ||
+      [aNativeKeyEvent type] == NSKeyUp) {
+    aKeyEvent.mNativeKeyCode = [aNativeKeyEvent keyCode];
+    aKeyEvent.mNativeModifierFlags = [aNativeKeyEvent modifierFlags];
+    nsAutoString nativeChars;
+    nsCocoaUtils::GetStringForNSString([aNativeKeyEvent characters], nativeChars);
+    aKeyEvent.mNativeCharacters.Assign(nativeChars);
+    nsAutoString nativeCharsIgnoringModifiers;
+    nsCocoaUtils::GetStringForNSString([aNativeKeyEvent charactersIgnoringModifiers], nativeCharsIgnoringModifiers);
+    aKeyEvent.mNativeCharactersIgnoringModifiers.Assign(nativeCharsIgnoringModifiers);
+  } else if ([aNativeKeyEvent type] == NSFlagsChanged) {
+    aKeyEvent.mNativeKeyCode = [aNativeKeyEvent keyCode];
+    aKeyEvent.mNativeModifierFlags = [aNativeKeyEvent modifierFlags];
+  }
+
+  aKeyEvent.mRefPoint = LayoutDeviceIntPoint(0, 0);
+  aKeyEvent.mIsChar = false; // XXX not used in XP level
+
+  UInt32 kbType = GetKbdType();
+  UInt32 nativeKeyCode = [aNativeKeyEvent keyCode];
+
+  aKeyEvent.mKeyCode =
+    ComputeGeckoKeyCode(nativeKeyCode, kbType, aKeyEvent.IsMeta());
+
+  switch (nativeKeyCode) {
+    case kVK_Command:
+    case kVK_Shift:
+    case kVK_Option:
+    case kVK_Control:
+      aKeyEvent.mLocation = nsIDOMKeyEvent::DOM_KEY_LOCATION_LEFT;
+      break;
+
+    case kVK_RightCommand:
+    case kVK_RightShift:
+    case kVK_RightOption:
+    case kVK_RightControl:
+      aKeyEvent.mLocation = nsIDOMKeyEvent::DOM_KEY_LOCATION_RIGHT;
+      break;
+
+    case kVK_ANSI_Keypad0:
+    case kVK_ANSI_Keypad1:
+    case kVK_ANSI_Keypad2:
+    case kVK_ANSI_Keypad3:
+    case kVK_ANSI_Keypad4:
+    case kVK_ANSI_Keypad5:
+    case kVK_ANSI_Keypad6:
+    case kVK_ANSI_Keypad7:
+    case kVK_ANSI_Keypad8:
+    case kVK_ANSI_Keypad9:
+    case kVK_ANSI_KeypadMultiply:
+    case kVK_ANSI_KeypadPlus:
+    case kVK_ANSI_KeypadMinus:
+    case kVK_ANSI_KeypadDecimal:
+    case kVK_ANSI_KeypadDivide:
+    case kVK_ANSI_KeypadEquals:
+    case kVK_ANSI_KeypadEnter:
+    case kVK_JIS_KeypadComma:
+    case kVK_Powerbook_KeypadEnter:
+      aKeyEvent.mLocation = nsIDOMKeyEvent::DOM_KEY_LOCATION_NUMPAD;
+      break;
+
+    default:
+      aKeyEvent.mLocation = nsIDOMKeyEvent::DOM_KEY_LOCATION_STANDARD;
+      break;
+  }
+
+  aKeyEvent.mIsRepeat =
+    ([aNativeKeyEvent type] == NSKeyDown) ? [aNativeKeyEvent isARepeat] : false;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::InitKeyEvent, "
+     "shift=%s, ctrl=%s, alt=%s, meta=%s",
+     this, OnOrOff(aKeyEvent.IsShift()), OnOrOff(aKeyEvent.IsControl()),
+     OnOrOff(aKeyEvent.IsAlt()), OnOrOff(aKeyEvent.IsMeta())));
+
+  if (IsPrintableKeyEvent(aNativeKeyEvent)) {
+    aKeyEvent.mKeyNameIndex = KEY_NAME_INDEX_USE_STRING;
+    // If insertText calls this method, let's use the string.
+    if (aInsertString && !aInsertString->IsEmpty() &&
+        !IsControlChar((*aInsertString)[0])) {
+      aKeyEvent.mKeyValue = *aInsertString;
+    }
+    // If meta key is pressed, the printable key layout may be switched from
+    // non-ASCII capable layout to ASCII capable, or from Dvorak to QWERTY.
+    // KeyboardEvent.key value should be the switched layout's character.
+    else if (aKeyEvent.IsMeta()) {
+      nsCocoaUtils::GetStringForNSString([aNativeKeyEvent characters],
+                                         aKeyEvent.mKeyValue);
+    }
+    // If control key is pressed, some keys may produce printable character via
+    // [aNativeKeyEvent characters].  Otherwise, translate input character of
+    // the key without control key.
+    else if (aKeyEvent.IsControl()) {
+      nsCocoaUtils::GetStringForNSString([aNativeKeyEvent characters],
+                                         aKeyEvent.mKeyValue);
+      if (aKeyEvent.mKeyValue.IsEmpty() ||
+          IsControlChar(aKeyEvent.mKeyValue[0])) {
+        NSUInteger cocoaState =
+          [aNativeKeyEvent modifierFlags] & ~NSControlKeyMask;
+        UInt32 carbonState = nsCocoaUtils::ConvertToCarbonModifier(cocoaState);
+        aKeyEvent.mKeyValue =
+          TranslateToChar(nativeKeyCode, carbonState, kbType);
+      }
+    }
+    // Otherwise, KeyboardEvent.key expose
+    // [aNativeKeyEvent characters] value.  However, if IME is open and the
+    // keyboard layout isn't ASCII capable, exposing the non-ASCII character
+    // doesn't match with other platform's behavior.  For the compatibility
+    // with other platform's Gecko, we need to set a translated character.
+    else if (IsOpenedIMEMode()) {
+      UInt32 state =
+        nsCocoaUtils::ConvertToCarbonModifier([aNativeKeyEvent modifierFlags]);
+      aKeyEvent.mKeyValue = TranslateToChar(nativeKeyCode, state, kbType);
+    } else {
+      nsCocoaUtils::GetStringForNSString([aNativeKeyEvent characters],
+                                         aKeyEvent.mKeyValue);
+      // If the key value is empty, the event may be a dead key event.
+      // If TranslateToChar() returns non-zero value, that means that
+      // the key may input a character with different dead key state.
+      if (aKeyEvent.mKeyValue.IsEmpty()) {
+        NSUInteger cocoaState = [aNativeKeyEvent modifierFlags];
+        UInt32 carbonState = nsCocoaUtils::ConvertToCarbonModifier(cocoaState);
+        if (TranslateToChar(nativeKeyCode, carbonState, kbType)) {
+          aKeyEvent.mKeyNameIndex = KEY_NAME_INDEX_Dead;
+        }
+      }
+    }
+
+    // Last resort.  If .key value becomes empty string, we should use
+    // charactersIgnoringModifiers, if it's available.
+    if (aKeyEvent.mKeyNameIndex == KEY_NAME_INDEX_USE_STRING &&
+        (aKeyEvent.mKeyValue.IsEmpty() ||
+         IsControlChar(aKeyEvent.mKeyValue[0]))) {
+      nsCocoaUtils::GetStringForNSString(
+        [aNativeKeyEvent charactersIgnoringModifiers], aKeyEvent.mKeyValue);
+      // But don't expose it if it's a control character.
+      if (!aKeyEvent.mKeyValue.IsEmpty() &&
+          IsControlChar(aKeyEvent.mKeyValue[0])) {
+        aKeyEvent.mKeyValue.Truncate();
+      }
+    }
+  } else {
+    // Compute the key for non-printable keys and some special printable keys.
+    aKeyEvent.mKeyNameIndex = ComputeGeckoKeyNameIndex(nativeKeyCode);
+  }
+
+  aKeyEvent.mCodeNameIndex = ComputeGeckoCodeNameIndex(nativeKeyCode);
+  MOZ_ASSERT(aKeyEvent.mCodeNameIndex != CODE_NAME_INDEX_USE_STRING);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK
+}
+
+void
+TISInputSourceWrapper::WillDispatchKeyboardEvent(
+                         NSEvent* aNativeKeyEvent,
+                         const nsAString* aInsertString,
+                         WidgetKeyboardEvent& aKeyEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Nothing to do here if the native key event is neither NSKeyDown nor
+  // NSKeyUp because accessing [aNativeKeyEvent characters] causes throwing
+  // an exception.
+  if ([aNativeKeyEvent type] != NSKeyDown &&
+      [aNativeKeyEvent type] != NSKeyUp) {
+    return;
+  }
+
+  UInt32 kbType = GetKbdType();
+
+  if (MOZ_LOG_TEST(gLog, LogLevel::Info)) {
+    nsAutoString chars;
+    nsCocoaUtils::GetStringForNSString([aNativeKeyEvent characters], chars);
+    NS_ConvertUTF16toUTF8 utf8Chars(chars);
+    char16_t uniChar = static_cast<char16_t>(aKeyEvent.mCharCode);
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TISInputSourceWrapper::WillDispatchKeyboardEvent, "
+       "aNativeKeyEvent=%p, [aNativeKeyEvent characters]=\"%s\", "
+       "aKeyEvent={ mMessage=%s, mCharCode=0x%X(%s) }, kbType=0x%X, "
+       "IsOpenedIMEMode()=%s",
+       this, aNativeKeyEvent, utf8Chars.get(),
+       GetGeckoKeyEventType(aKeyEvent), aKeyEvent.mCharCode,
+       uniChar ? NS_ConvertUTF16toUTF8(&uniChar, 1).get() : "",
+       kbType, TrueOrFalse(IsOpenedIMEMode())));
+  }
+
+  nsAutoString insertStringForCharCode;
+  ComputeInsertStringForCharCode(aNativeKeyEvent, aKeyEvent, aInsertString,
+                                 insertStringForCharCode);
+
+  // The mCharCode was set from mKeyValue. However, for example, when Ctrl key
+  // is pressed, its value should indicate an ASCII character for backward
+  // compatibility rather than inputting character without the modifiers.
+  // Therefore, we need to modify mCharCode value here.
+  uint32_t charCode =
+    insertStringForCharCode.IsEmpty() ? 0 : insertStringForCharCode[0];
+  aKeyEvent.SetCharCode(charCode);
+  // this is not a special key  XXX not used in XP
+  aKeyEvent.mIsChar = (aKeyEvent.mMessage == eKeyPress);
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::WillDispatchKeyboardEvent, "
+     "aKeyEvent.mKeyCode=0x%X, aKeyEvent.mCharCode=0x%X",
+     this, aKeyEvent.mKeyCode, aKeyEvent.mCharCode));
+
+  TISInputSourceWrapper USLayout("com.apple.keylayout.US");
+  bool isRomanKeyboardLayout = IsASCIICapable();
+
+  UInt32 key = [aNativeKeyEvent keyCode];
+
+  // Caps lock and num lock modifier state:
+  UInt32 lockState = 0;
+  if ([aNativeKeyEvent modifierFlags] & NSAlphaShiftKeyMask) {
+    lockState |= alphaLock;
+  }
+  if ([aNativeKeyEvent modifierFlags] & NSNumericPadKeyMask) {
+    lockState |= kEventKeyModifierNumLockMask;
+  }
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::WillDispatchKeyboardEvent, "
+     "isRomanKeyboardLayout=%s, key=0x%X",
+     this, TrueOrFalse(isRomanKeyboardLayout), kbType, key));
+
+  nsString str;
+
+  // normal chars
+  uint32_t unshiftedChar = TranslateToChar(key, lockState, kbType);
+  UInt32 shiftLockMod = shiftKey | lockState;
+  uint32_t shiftedChar = TranslateToChar(key, shiftLockMod, kbType);
+
+  // characters generated with Cmd key
+  // XXX we should remove CapsLock state, which changes characters from
+  //     Latin to Cyrillic with Russian layout on 10.4 only when Cmd key
+  //     is pressed.
+  UInt32 numState = (lockState & ~alphaLock); // only num lock state
+  uint32_t uncmdedChar = TranslateToChar(key, numState, kbType);
+  UInt32 shiftNumMod = numState | shiftKey;
+  uint32_t uncmdedShiftChar = TranslateToChar(key, shiftNumMod, kbType);
+  uint32_t uncmdedUSChar = USLayout.TranslateToChar(key, numState, kbType);
+  UInt32 cmdNumMod = cmdKey | numState;
+  uint32_t cmdedChar = TranslateToChar(key, cmdNumMod, kbType);
+  UInt32 cmdShiftNumMod = shiftKey | cmdNumMod;
+  uint32_t cmdedShiftChar = TranslateToChar(key, cmdShiftNumMod, kbType);
+
+  // Is the keyboard layout changed by Cmd key?
+  // E.g., Arabic, Russian, Hebrew, Greek and Dvorak-QWERTY.
+  bool isCmdSwitchLayout = uncmdedChar != cmdedChar;
+  // Is the keyboard layout for Latin, but Cmd key switches the layout?
+  // I.e., Dvorak-QWERTY
+  bool isDvorakQWERTY = isCmdSwitchLayout && isRomanKeyboardLayout;
+
+  // If the current keyboard is not Dvorak-QWERTY or Cmd is not pressed,
+  // we should append unshiftedChar and shiftedChar for handling the
+  // normal characters.  These are the characters that the user is most
+  // likely to associate with this key.
+  if ((unshiftedChar || shiftedChar) &&
+      (!aKeyEvent.IsMeta() || !isDvorakQWERTY)) {
+    AlternativeCharCode altCharCodes(unshiftedChar, shiftedChar);
+    aKeyEvent.mAlternativeCharCodes.AppendElement(altCharCodes);
+  }
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::WillDispatchKeyboardEvent, "
+     "aKeyEvent.isMeta=%s, isDvorakQWERTY=%s, "
+     "unshiftedChar=U+%X, shiftedChar=U+%X",
+     this, OnOrOff(aKeyEvent.IsMeta()), TrueOrFalse(isDvorakQWERTY),
+     unshiftedChar, shiftedChar));
+
+  // Most keyboard layouts provide the same characters in the NSEvents
+  // with Command+Shift as with Command.  However, with Command+Shift we
+  // want the character on the second level.  e.g. With a US QWERTY
+  // layout, we want "?" when the "/","?" key is pressed with
+  // Command+Shift.
+
+  // On a German layout, the OS gives us '/' with Cmd+Shift+SS(eszett)
+  // even though Cmd+SS is 'SS' and Shift+'SS' is '?'.  This '/' seems
+  // like a hack to make the Cmd+"?" event look the same as the Cmd+"?"
+  // event on a US keyboard.  The user thinks they are typing Cmd+"?", so
+  // we'll prefer the "?" character, replacing mCharCode with shiftedChar
+  // when Shift is pressed.  However, in case there is a layout where the
+  // character unique to Cmd+Shift is the character that the user expects,
+  // we'll send it as an alternative char.
+  bool hasCmdShiftOnlyChar =
+    cmdedChar != cmdedShiftChar && uncmdedShiftChar != cmdedShiftChar;
+  uint32_t originalCmdedShiftChar = cmdedShiftChar;
+
+  // If we can make a good guess at the characters that the user would
+  // expect this key combination to produce (with and without Shift) then
+  // use those characters.  This also corrects for CapsLock, which was
+  // ignored above.
+  if (!isCmdSwitchLayout) {
+    // The characters produced with Command seem similar to those without
+    // Command.
+    if (unshiftedChar) {
+      cmdedChar = unshiftedChar;
+    }
+    if (shiftedChar) {
+      cmdedShiftChar = shiftedChar;
+    }
+  } else if (uncmdedUSChar == cmdedChar) {
+    // It looks like characters from a US layout are provided when Command
+    // is down.
+    uint32_t ch = USLayout.TranslateToChar(key, lockState, kbType);
+    if (ch) {
+      cmdedChar = ch;
+    }
+    ch = USLayout.TranslateToChar(key, shiftLockMod, kbType);
+    if (ch) {
+      cmdedShiftChar = ch;
+    }
+  }
+
+  // If the current keyboard layout is switched by the Cmd key,
+  // we should append cmdedChar and shiftedCmdChar that are
+  // Latin char for the key.
+  // If the keyboard layout is Dvorak-QWERTY, we should append them only when
+  // command key is pressed because when command key isn't pressed, uncmded
+  // chars have been appended already.
+  if ((cmdedChar || cmdedShiftChar) && isCmdSwitchLayout &&
+      (aKeyEvent.IsMeta() || !isDvorakQWERTY)) {
+    AlternativeCharCode altCharCodes(cmdedChar, cmdedShiftChar);
+    aKeyEvent.mAlternativeCharCodes.AppendElement(altCharCodes);
+  }
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::WillDispatchKeyboardEvent, "
+     "hasCmdShiftOnlyChar=%s, isCmdSwitchLayout=%s, isDvorakQWERTY=%s, "
+     "cmdedChar=U+%X, cmdedShiftChar=U+%X",
+     this, TrueOrFalse(hasCmdShiftOnlyChar), TrueOrFalse(isDvorakQWERTY),
+     TrueOrFalse(isDvorakQWERTY), cmdedChar, cmdedShiftChar));
+  // Special case for 'SS' key of German layout. See the comment of
+  // hasCmdShiftOnlyChar definition for the detail.
+  if (hasCmdShiftOnlyChar && originalCmdedShiftChar) {
+    AlternativeCharCode altCharCodes(0, originalCmdedShiftChar);
+    aKeyEvent.mAlternativeCharCodes.AppendElement(altCharCodes);
+  }
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::WillDispatchKeyboardEvent, "
+     "hasCmdShiftOnlyChar=%s, originalCmdedShiftChar=U+%X",
+     this, TrueOrFalse(hasCmdShiftOnlyChar), originalCmdedShiftChar));
+
+  NS_OBJC_END_TRY_ABORT_BLOCK
+}
+
+uint32_t
+TISInputSourceWrapper::ComputeGeckoKeyCode(UInt32 aNativeKeyCode,
+                                           UInt32 aKbType,
+                                           bool aCmdIsPressed)
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TISInputSourceWrapper::ComputeGeckoKeyCode, aNativeKeyCode=0x%X, "
+     "aKbType=0x%X, aCmdIsPressed=%s, IsOpenedIMEMode()=%s, "
+     "IsASCIICapable()=%s",
+     this, aNativeKeyCode, aKbType, TrueOrFalse(aCmdIsPressed),
+     TrueOrFalse(IsOpenedIMEMode()), TrueOrFalse(IsASCIICapable())));
+
+  switch (aNativeKeyCode) {
+    case kVK_Space:             return NS_VK_SPACE;
+    case kVK_Escape:            return NS_VK_ESCAPE;
+
+    // modifiers
+    case kVK_RightCommand:
+    case kVK_Command:           return NS_VK_META;
+    case kVK_RightShift:
+    case kVK_Shift:             return NS_VK_SHIFT;
+    case kVK_CapsLock:          return NS_VK_CAPS_LOCK;
+    case kVK_RightControl:
+    case kVK_Control:           return NS_VK_CONTROL;
+    case kVK_RightOption:
+    case kVK_Option:            return NS_VK_ALT;
+
+    case kVK_ANSI_KeypadClear:  return NS_VK_CLEAR;
+
+    // function keys
+    case kVK_F1:                return NS_VK_F1;
+    case kVK_F2:                return NS_VK_F2;
+    case kVK_F3:                return NS_VK_F3;
+    case kVK_F4:                return NS_VK_F4;
+    case kVK_F5:                return NS_VK_F5;
+    case kVK_F6:                return NS_VK_F6;
+    case kVK_F7:                return NS_VK_F7;
+    case kVK_F8:                return NS_VK_F8;
+    case kVK_F9:                return NS_VK_F9;
+    case kVK_F10:               return NS_VK_F10;
+    case kVK_F11:               return NS_VK_F11;
+    case kVK_F12:               return NS_VK_F12;
+    // case kVK_F13:               return NS_VK_F13;  // clash with the 3 below
+    // case kVK_F14:               return NS_VK_F14;
+    // case kVK_F15:               return NS_VK_F15;
+    case kVK_F16:               return NS_VK_F16;
+    case kVK_F17:               return NS_VK_F17;
+    case kVK_F18:               return NS_VK_F18;
+    case kVK_F19:               return NS_VK_F19;
+
+    case kVK_PC_Pause:          return NS_VK_PAUSE;
+    case kVK_PC_ScrollLock:     return NS_VK_SCROLL_LOCK;
+    case kVK_PC_PrintScreen:    return NS_VK_PRINTSCREEN;
+
+    // keypad
+    case kVK_ANSI_Keypad0:      return NS_VK_NUMPAD0;
+    case kVK_ANSI_Keypad1:      return NS_VK_NUMPAD1;
+    case kVK_ANSI_Keypad2:      return NS_VK_NUMPAD2;
+    case kVK_ANSI_Keypad3:      return NS_VK_NUMPAD3;
+    case kVK_ANSI_Keypad4:      return NS_VK_NUMPAD4;
+    case kVK_ANSI_Keypad5:      return NS_VK_NUMPAD5;
+    case kVK_ANSI_Keypad6:      return NS_VK_NUMPAD6;
+    case kVK_ANSI_Keypad7:      return NS_VK_NUMPAD7;
+    case kVK_ANSI_Keypad8:      return NS_VK_NUMPAD8;
+    case kVK_ANSI_Keypad9:      return NS_VK_NUMPAD9;
+
+    case kVK_ANSI_KeypadMultiply: return NS_VK_MULTIPLY;
+    case kVK_ANSI_KeypadPlus:     return NS_VK_ADD;
+    case kVK_ANSI_KeypadMinus:    return NS_VK_SUBTRACT;
+    case kVK_ANSI_KeypadDecimal:  return NS_VK_DECIMAL;
+    case kVK_ANSI_KeypadDivide:   return NS_VK_DIVIDE;
+
+    case kVK_JIS_KeypadComma:   return NS_VK_SEPARATOR;
+
+    // IME keys
+    case kVK_JIS_Eisu:          return NS_VK_EISU;
+    case kVK_JIS_Kana:          return NS_VK_KANA;
+
+    // these may clash with forward delete and help
+    case kVK_PC_Insert:         return NS_VK_INSERT;
+    case kVK_PC_Delete:         return NS_VK_DELETE;
+
+    case kVK_PC_Backspace:      return NS_VK_BACK;
+    case kVK_Tab:               return NS_VK_TAB;
+
+    case kVK_Home:              return NS_VK_HOME;
+    case kVK_End:               return NS_VK_END;
+
+    case kVK_PageUp:            return NS_VK_PAGE_UP;
+    case kVK_PageDown:          return NS_VK_PAGE_DOWN;
+
+    case kVK_LeftArrow:         return NS_VK_LEFT;
+    case kVK_RightArrow:        return NS_VK_RIGHT;
+    case kVK_UpArrow:           return NS_VK_UP;
+    case kVK_DownArrow:         return NS_VK_DOWN;
+
+    case kVK_PC_ContextMenu:    return NS_VK_CONTEXT_MENU;
+
+    case kVK_ANSI_1:            return NS_VK_1;
+    case kVK_ANSI_2:            return NS_VK_2;
+    case kVK_ANSI_3:            return NS_VK_3;
+    case kVK_ANSI_4:            return NS_VK_4;
+    case kVK_ANSI_5:            return NS_VK_5;
+    case kVK_ANSI_6:            return NS_VK_6;
+    case kVK_ANSI_7:            return NS_VK_7;
+    case kVK_ANSI_8:            return NS_VK_8;
+    case kVK_ANSI_9:            return NS_VK_9;
+    case kVK_ANSI_0:            return NS_VK_0;
+
+    case kVK_ANSI_KeypadEnter:
+    case kVK_Return:
+    case kVK_Powerbook_KeypadEnter: return NS_VK_RETURN;
+  }
+
+  // If Cmd key is pressed, that causes switching keyboard layout temporarily.
+  // E.g., Dvorak-QWERTY.  Therefore, if Cmd key is pressed, we should honor it.
+  UInt32 modifiers = aCmdIsPressed ? cmdKey : 0;
+
+  uint32_t charCode = TranslateToChar(aNativeKeyCode, modifiers, aKbType);
+
+  // Special case for Mac.  Mac inputs Yen sign (U+00A5) directly instead of
+  // Back slash (U+005C).  We should return NS_VK_BACK_SLASH for compatibility
+  // with other platforms.
+  // XXX How about Won sign (U+20A9) which has same problem as Yen sign?
+  if (charCode == 0x00A5) {
+    return NS_VK_BACK_SLASH;
+  }
+
+  uint32_t keyCode = WidgetUtils::ComputeKeyCodeFromChar(charCode);
+  if (keyCode) {
+    return keyCode;
+  }
+
+  // If the unshifed char isn't an ASCII character, use shifted char.
+  charCode = TranslateToChar(aNativeKeyCode, modifiers | shiftKey, aKbType);
+  keyCode = WidgetUtils::ComputeKeyCodeFromChar(charCode);
+  if (keyCode) {
+    return keyCode;
+  }
+
+  // If this is ASCII capable, give up to compute it.
+  if (IsASCIICapable()) {
+    return 0;
+  }
+
+  // Retry with ASCII capable keyboard layout.
+  TISInputSourceWrapper currentKeyboardLayout;
+  currentKeyboardLayout.InitByCurrentASCIICapableKeyboardLayout();
+  NS_ENSURE_TRUE(mInputSource != currentKeyboardLayout.mInputSource, 0);
+  keyCode = currentKeyboardLayout.ComputeGeckoKeyCode(aNativeKeyCode, aKbType,
+                                                      aCmdIsPressed);
+
+  // However, if keyCode isn't for an alphabet keys or a numeric key, we should
+  // ignore it.  For example, comma key of Thai layout is same as close-square-
+  // bracket key of US layout and an unicode character key of Thai layout is
+  // same as comma key of US layout.  If we return NS_VK_COMMA for latter key,
+  // web application developers cannot distinguish with the former key.
+  return ((keyCode >= NS_VK_A && keyCode <= NS_VK_Z) ||
+          (keyCode >= NS_VK_0 && keyCode <= NS_VK_9)) ? keyCode : 0;
+}
+
+// static
+KeyNameIndex
+TISInputSourceWrapper::ComputeGeckoKeyNameIndex(UInt32 aNativeKeyCode)
+{
+  // NOTE:
+  //   When unsupported keys like Convert, Nonconvert of Japanese keyboard is
+  //   pressed:
+  //     on 10.6.x, 'A' key event is fired (and also actually 'a' is inserted).
+  //     on 10.7.x, Nothing happens.
+  //     on 10.8.x, Nothing happens.
+  //     on 10.9.x, FlagsChanged event is fired with keyCode 0xFF.
+  switch (aNativeKeyCode) {
+
+#define NS_NATIVE_KEY_TO_DOM_KEY_NAME_INDEX(aNativeKey, aKeyNameIndex) \
+    case aNativeKey: return aKeyNameIndex;
+
+#include "NativeKeyToDOMKeyName.h"
+
+#undef NS_NATIVE_KEY_TO_DOM_KEY_NAME_INDEX
+
+    default:
+      return KEY_NAME_INDEX_Unidentified;
+  }
+}
+
+// static
+CodeNameIndex
+TISInputSourceWrapper::ComputeGeckoCodeNameIndex(UInt32 aNativeKeyCode)
+{
+  switch (aNativeKeyCode) {
+
+#define NS_NATIVE_KEY_TO_DOM_CODE_NAME_INDEX(aNativeKey, aCodeNameIndex) \
+    case aNativeKey: return aCodeNameIndex;
+
+#include "NativeKeyToDOMCodeName.h"
+
+#undef NS_NATIVE_KEY_TO_DOM_CODE_NAME_INDEX
+
+    default:
+      return CODE_NAME_INDEX_UNKNOWN;
+  }
+}
+
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  TextInputHandler implementation (static methods)
+ *
+ ******************************************************************************/
+
+NSUInteger TextInputHandler::sLastModifierState = 0;
+
+// static
+CFArrayRef
+TextInputHandler::CreateAllKeyboardLayoutList()
+{
+  const void* keys[] = { kTISPropertyInputSourceType };
+  const void* values[] = { kTISTypeKeyboardLayout };
+  CFDictionaryRef filter =
+    ::CFDictionaryCreate(kCFAllocatorDefault, keys, values, 1, NULL, NULL);
+  NS_ASSERTION(filter, "failed to create the filter");
+  CFArrayRef list = ::TISCreateInputSourceList(filter, true);
+  ::CFRelease(filter);
+  return list;
+}
+
+// static
+void
+TextInputHandler::DebugPrintAllKeyboardLayouts()
+{
+  if (MOZ_LOG_TEST(gLog, LogLevel::Info)) {
+    CFArrayRef list = CreateAllKeyboardLayoutList();
+    MOZ_LOG(gLog, LogLevel::Info, ("Keyboard layout configuration:"));
+    CFIndex idx = ::CFArrayGetCount(list);
+    TISInputSourceWrapper tis;
+    for (CFIndex i = 0; i < idx; ++i) {
+      TISInputSourceRef inputSource = static_cast<TISInputSourceRef>(
+        const_cast<void *>(::CFArrayGetValueAtIndex(list, i)));
+      tis.InitByTISInputSourceRef(inputSource);
+      nsAutoString name, isid;
+      tis.GetLocalizedName(name);
+      tis.GetInputSourceID(isid);
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("  %s\t<%s>%s%s\n",
+         NS_ConvertUTF16toUTF8(name).get(),
+         NS_ConvertUTF16toUTF8(isid).get(),
+         tis.IsASCIICapable() ? "" : "\t(Isn't ASCII capable)",
+         tis.IsKeyboardLayout() && tis.GetUCKeyboardLayout() ?
+           "" : "\t(uchr is NOT AVAILABLE)"));
+    }
+    ::CFRelease(list);
+  }
+}
+
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  TextInputHandler implementation
+ *
+ ******************************************************************************/
+
+TextInputHandler::TextInputHandler(nsChildView* aWidget,
+                                   NSView<mozView> *aNativeView) :
+  IMEInputHandler(aWidget, aNativeView)
+{
+  EnsureToLogAllKeyboardLayoutsAndIMEs();
+  [mView installTextInputHandler:this];
+}
+
+TextInputHandler::~TextInputHandler()
+{
+  [mView uninstallTextInputHandler];
+}
+
+bool
+TextInputHandler::HandleKeyDownEvent(NSEvent* aNativeEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyDownEvent, "
+       "widget has been already destroyed", this));
+    return false;
+  }
+
+  // Insert empty line to the log for easier to read.
+  MOZ_LOG(gLog, LogLevel::Info, (""));
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::HandleKeyDownEvent, aNativeEvent=%p, "
+     "type=%s, keyCode=%lld (0x%X), modifierFlags=0x%X, characters=\"%s\", "
+     "charactersIgnoringModifiers=\"%s\"",
+     this, aNativeEvent, GetNativeKeyEventType(aNativeEvent),
+     [aNativeEvent keyCode], [aNativeEvent keyCode],
+     [aNativeEvent modifierFlags], GetCharacters([aNativeEvent characters]),
+     GetCharacters([aNativeEvent charactersIgnoringModifiers])));
+
+  // Except when Command key is pressed, we should hide mouse cursor until
+  // next mousemove.  Handling here means that:
+  // - Don't hide mouse cursor at pressing modifier key
+  // - Hide mouse cursor even if the key event will be handled by IME (i.e.,
+  //   even without dispatching eKeyPress events)
+  // - Hide mouse cursor even when a plugin has focus
+  if (!([aNativeEvent modifierFlags] & NSCommandKeyMask)) {
+    [NSCursor setHiddenUntilMouseMoves:YES];
+  }
+
+  RefPtr<nsChildView> widget(mWidget);
+
+  KeyEventState* currentKeyEvent = PushKeyEvent(aNativeEvent);
+  AutoKeyEventStateCleaner remover(this);
+
+  ComplexTextInputPanel* ctiPanel = ComplexTextInputPanel::GetSharedComplexTextInputPanel();
+  if (ctiPanel && ctiPanel->IsInComposition()) {
+    nsAutoString committed;
+    ctiPanel->InterpretKeyEvent(aNativeEvent, committed);
+    if (!committed.IsEmpty()) {
+      nsresult rv = mDispatcher->BeginNativeInputTransaction();
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        MOZ_LOG(gLog, LogLevel::Error,
+          ("%p IMEInputHandler::HandleKeyDownEvent, "
+           "FAILED, due to BeginNativeInputTransaction() failure "
+           "at dispatching keydown for ComplexTextInputPanel", this));
+        return false;
+      }
+
+      WidgetKeyboardEvent imeEvent(true, eKeyDown, widget);
+      currentKeyEvent->InitKeyEvent(this, imeEvent);
+      imeEvent.mPluginTextEventString.Assign(committed);
+      nsEventStatus status = nsEventStatus_eIgnore;
+      mDispatcher->DispatchKeyboardEvent(eKeyDown, imeEvent, status,
+                                         currentKeyEvent);
+    }
+    return true;
+  }
+
+  NSResponder* firstResponder = [[mView window] firstResponder];
+
+  nsresult rv = mDispatcher->BeginNativeInputTransaction();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+      MOZ_LOG(gLog, LogLevel::Error,
+        ("%p IMEInputHandler::HandleKeyDownEvent, "
+         "FAILED, due to BeginNativeInputTransaction() failure "
+         "at dispatching keydown for ordinal cases", this));
+    return false;
+  }
+
+  WidgetKeyboardEvent keydownEvent(true, eKeyDown, widget);
+  currentKeyEvent->InitKeyEvent(this, keydownEvent);
+
+  nsEventStatus status = nsEventStatus_eIgnore;
+  mDispatcher->DispatchKeyboardEvent(eKeyDown, keydownEvent, status,
+                                     currentKeyEvent);
+  currentKeyEvent->mKeyDownHandled =
+    (status == nsEventStatus_eConsumeNoDefault);
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyDownEvent, "
+       "widget was destroyed by keydown event", this));
+    return currentKeyEvent->IsDefaultPrevented();
+  }
+
+  // The key down event may have shifted the focus, in which
+  // case we should not fire the key press.
+  // XXX This is a special code only on Cocoa widget, why is this needed?
+  if (firstResponder != [[mView window] firstResponder]) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyDownEvent, "
+       "view lost focus by keydown event", this));
+    return currentKeyEvent->IsDefaultPrevented();
+  }
+
+  if (currentKeyEvent->IsDefaultPrevented()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyDownEvent, "
+       "keydown event's default is prevented", this));
+    return true;
+  }
+
+  // Let Cocoa interpret the key events, caching IsIMEComposing first.
+  bool wasComposing = IsIMEComposing();
+  bool interpretKeyEventsCalled = false;
+  // Don't call interpretKeyEvents when a plugin has focus.  If we call it,
+  // for example, a character is inputted twice during a composition in e10s
+  // mode.
+  if (!widget->IsPluginFocused() && (IsIMEEnabled() || IsASCIICapableOnly())) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyDownEvent, calling interpretKeyEvents",
+       this));
+    [mView interpretKeyEvents:[NSArray arrayWithObject:aNativeEvent]];
+    interpretKeyEventsCalled = true;
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyDownEvent, called interpretKeyEvents",
+       this));
+  }
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyDownEvent, widget was destroyed",
+       this));
+    return currentKeyEvent->IsDefaultPrevented();
+  }
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::HandleKeyDownEvent, wasComposing=%s, "
+     "IsIMEComposing()=%s",
+     this, TrueOrFalse(wasComposing), TrueOrFalse(IsIMEComposing())));
+
+  if (currentKeyEvent->CanDispatchKeyPressEvent() &&
+      !wasComposing && !IsIMEComposing()) {
+    rv = mDispatcher->BeginNativeInputTransaction();
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+        MOZ_LOG(gLog, LogLevel::Error,
+          ("%p IMEInputHandler::HandleKeyDownEvent, "
+           "FAILED, due to BeginNativeInputTransaction() failure "
+           "at dispatching keypress", this));
+      return false;
+    }
+
+    WidgetKeyboardEvent keypressEvent(true, eKeyPress, widget);
+    currentKeyEvent->InitKeyEvent(this, keypressEvent);
+
+    // If we called interpretKeyEvents and this isn't normal character input
+    // then IME probably ate the event for some reason. We do not want to
+    // send a key press event in that case.
+    // TODO:
+    // There are some other cases which IME eats the current event.
+    // 1. If key events were nested during calling interpretKeyEvents, it means
+    //    that IME did something.  Then, we should do nothing.
+    // 2. If one or more commands are called like "deleteBackward", we should
+    //    dispatch keypress event at that time.  Note that the command may have
+    //    been a converted or generated action by IME.  Then, we shouldn't do
+    //    our default action for this key.
+    if (!(interpretKeyEventsCalled &&
+          IsNormalCharInputtingEvent(keypressEvent))) {
+      currentKeyEvent->mKeyPressDispatched =
+        mDispatcher->MaybeDispatchKeypressEvents(keypressEvent, status,
+                                                 currentKeyEvent);
+      currentKeyEvent->mKeyPressHandled =
+        (status == nsEventStatus_eConsumeNoDefault);
+      currentKeyEvent->mKeyPressDispatched = true;
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("%p TextInputHandler::HandleKeyDownEvent, keypress event dispatched",
+         this));
+    }
+  }
+
+  // Note: mWidget might have become null here. Don't count on it from here on.
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::HandleKeyDownEvent, "
+     "keydown handled=%s, keypress handled=%s, causedOtherKeyEvents=%s, "
+     "compositionDispatched=%s",
+     this, TrueOrFalse(currentKeyEvent->mKeyDownHandled),
+     TrueOrFalse(currentKeyEvent->mKeyPressHandled),
+     TrueOrFalse(currentKeyEvent->mCausedOtherKeyEvents),
+     TrueOrFalse(currentKeyEvent->mCompositionDispatched)));
+  // Insert empty line to the log for easier to read.
+  MOZ_LOG(gLog, LogLevel::Info, (""));
+  return currentKeyEvent->IsDefaultPrevented();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+void
+TextInputHandler::HandleKeyUpEvent(NSEvent* aNativeEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::HandleKeyUpEvent, aNativeEvent=%p, "
+     "type=%s, keyCode=%lld (0x%X), modifierFlags=0x%X, characters=\"%s\", "
+     "charactersIgnoringModifiers=\"%s\", "
+     "IsIMEComposing()=%s",
+     this, aNativeEvent, GetNativeKeyEventType(aNativeEvent),
+     [aNativeEvent keyCode], [aNativeEvent keyCode],
+     [aNativeEvent modifierFlags], GetCharacters([aNativeEvent characters]),
+     GetCharacters([aNativeEvent charactersIgnoringModifiers]),
+     TrueOrFalse(IsIMEComposing())));
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleKeyUpEvent, "
+       "widget has been already destroyed", this));
+    return;
+  }
+
+  nsresult rv = mDispatcher->BeginNativeInputTransaction();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+      MOZ_LOG(gLog, LogLevel::Error,
+        ("%p IMEInputHandler::HandleKeyUpEvent, "
+         "FAILED, due to BeginNativeInputTransaction() failure", this));
+    return;
+  }
+
+  WidgetKeyboardEvent keyupEvent(true, eKeyUp, mWidget);
+  InitKeyEvent(aNativeEvent, keyupEvent);
+
+  KeyEventState currentKeyEvent(aNativeEvent);
+  nsEventStatus status = nsEventStatus_eIgnore;
+  mDispatcher->DispatchKeyboardEvent(eKeyUp, keyupEvent, status,
+                                     &currentKeyEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+TextInputHandler::HandleFlagsChanged(NSEvent* aNativeEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::HandleFlagsChanged, "
+       "widget has been already destroyed", this));
+    return;
+  }
+
+  RefPtr<nsChildView> kungFuDeathGrip(mWidget);
+  mozilla::Unused << kungFuDeathGrip; // Not referenced within this function
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::HandleFlagsChanged, aNativeEvent=%p, "
+     "type=%s, keyCode=%s (0x%X), modifierFlags=0x%08X, "
+     "sLastModifierState=0x%08X, IsIMEComposing()=%s",
+     this, aNativeEvent, GetNativeKeyEventType(aNativeEvent),
+     GetKeyNameForNativeKeyCode([aNativeEvent keyCode]), [aNativeEvent keyCode],
+     [aNativeEvent modifierFlags], sLastModifierState,
+     TrueOrFalse(IsIMEComposing())));
+
+  MOZ_ASSERT([aNativeEvent type] == NSFlagsChanged);
+
+  NSUInteger diff = [aNativeEvent modifierFlags] ^ sLastModifierState;
+  // Device dependent flags for left-control key, both shift keys, both command
+  // keys and both option keys have been defined in Next's SDK.  But we
+  // shouldn't use it directly as far as possible since Cocoa SDK doesn't
+  // define them.  Fortunately, we need them only when we dispatch keyup
+  // events.  So, we can usually know the actual relation between keyCode and
+  // device dependent flags.  However, we need to remove following flags first
+  // since the differences don't indicate modifier key state.
+  // NX_STYLUSPROXIMITYMASK: Probably used for pen like device.
+  // kCGEventFlagMaskNonCoalesced (= NX_NONCOALSESCEDMASK): See the document for
+  // Quartz Event Services.
+  diff &= ~(NX_STYLUSPROXIMITYMASK | kCGEventFlagMaskNonCoalesced);
+
+  switch ([aNativeEvent keyCode]) {
+    // CapsLock state and other modifier states are different:
+    // CapsLock state does not revert when the CapsLock key goes up, as the
+    // modifier state does for other modifier keys on key up.
+    case kVK_CapsLock: {
+      // Fire key down event for caps lock.
+      DispatchKeyEventForFlagsChanged(aNativeEvent, true);
+      // XXX should we fire keyup event too? The keyup event for CapsLock key
+      // is never dispatched on Gecko.
+      // XXX WebKit dispatches keydown event when CapsLock is locked, otherwise,
+      // keyup event.  If we do so, we cannot keep the consistency with other
+      // platform's behavior...
+      break;
+    }
+
+    // If the event is caused by pressing or releasing a modifier key, just
+    // dispatch the key's event.
+    case kVK_Shift:
+    case kVK_RightShift:
+    case kVK_Command:
+    case kVK_RightCommand:
+    case kVK_Control:
+    case kVK_RightControl:
+    case kVK_Option:
+    case kVK_RightOption:
+    case kVK_Help: {
+      // We assume that at most one modifier is changed per event if the event
+      // is caused by pressing or releasing a modifier key.
+      bool isKeyDown = ([aNativeEvent modifierFlags] & diff) != 0;
+      DispatchKeyEventForFlagsChanged(aNativeEvent, isKeyDown);
+      // XXX Some applications might send the event with incorrect device-
+      //     dependent flags.
+      if (isKeyDown && ((diff & ~NSDeviceIndependentModifierFlagsMask) != 0)) {
+        unsigned short keyCode = [aNativeEvent keyCode];
+        const ModifierKey* modifierKey =
+          GetModifierKeyForDeviceDependentFlags(diff);
+        if (modifierKey && modifierKey->keyCode != keyCode) {
+          // Although, we're not sure the actual cause of this case, the stored
+          // modifier information and the latest key event information may be
+          // mismatched. Then, let's reset the stored information.
+          // NOTE: If this happens, it may fail to handle NSFlagsChanged event
+          // in the default case (below). However, it's the rare case handler
+          // and this case occurs rarely. So, we can ignore the edge case bug.
+          NS_WARNING("Resetting stored modifier key information");
+          mModifierKeys.Clear();
+          modifierKey = nullptr;
+        }
+        if (!modifierKey) {
+          mModifierKeys.AppendElement(ModifierKey(diff, keyCode));
+        }
+      }
+      break;
+    }
+
+    // Currently we don't support Fn key since other browsers don't dispatch
+    // events for it and we don't have keyCode for this key.
+    // It should be supported when we implement .key and .char.
+    case kVK_Function:
+      break;
+
+    // If the event is caused by something else than pressing or releasing a
+    // single modifier key (for example by the app having been deactivated
+    // using command-tab), use the modifiers themselves to determine which
+    // key's event to dispatch, and whether it's a keyup or keydown event.
+    // In all cases we assume one or more modifiers are being deactivated
+    // (never activated) -- otherwise we'd have received one or more events
+    // corresponding to a single modifier key being pressed.
+    default: {
+      NSUInteger modifiers = sLastModifierState;
+      for (int32_t bit = 0; bit < 32; ++bit) {
+        NSUInteger flag = 1 << bit;
+        if (!(diff & flag)) {
+          continue;
+        }
+
+        // Given correct information from the application, a flag change here
+        // will normally be a deactivation (except for some lockable modifiers
+        // such as CapsLock).  But some applications (like VNC) can send an
+        // activating event with a zero keyCode.  So we need to check for that
+        // here.
+        bool dispatchKeyDown = ((flag & [aNativeEvent modifierFlags]) != 0);
+
+        unsigned short keyCode = 0;
+        if (flag & NSDeviceIndependentModifierFlagsMask) {
+          switch (flag) {
+            case NSAlphaShiftKeyMask:
+              keyCode = kVK_CapsLock;
+              dispatchKeyDown = true;
+              break;
+
+            case NSNumericPadKeyMask:
+              // NSNumericPadKeyMask is fired by VNC a lot. But not all of
+              // these events can really be Clear key events, so we just ignore
+              // them.
+              continue;
+
+            case NSHelpKeyMask:
+              keyCode = kVK_Help;
+              break;
+
+            case NSFunctionKeyMask:
+              // An NSFunctionKeyMask change here will normally be a
+              // deactivation.  But sometimes it will be an activation send (by
+              // VNC for example) with a zero keyCode.
+              continue;
+
+            // These cases (NSShiftKeyMask, NSControlKeyMask, NSAlternateKeyMask
+            // and NSCommandKeyMask) should be handled by the other branch of
+            // the if statement, below (which handles device dependent flags).
+            // However, some applications (like VNC) can send key events without
+            // any device dependent flags, so we handle them here instead.
+            case NSShiftKeyMask:
+              keyCode = (modifiers & 0x0004) ? kVK_RightShift : kVK_Shift;
+              break;
+            case NSControlKeyMask:
+              keyCode = (modifiers & 0x2000) ? kVK_RightControl : kVK_Control;
+              break;
+            case NSAlternateKeyMask:
+              keyCode = (modifiers & 0x0040) ? kVK_RightOption : kVK_Option;
+              break;
+            case NSCommandKeyMask:
+              keyCode = (modifiers & 0x0010) ? kVK_RightCommand : kVK_Command;
+              break;
+
+            default:
+              continue;
+          }
+        } else {
+          const ModifierKey* modifierKey =
+            GetModifierKeyForDeviceDependentFlags(flag);
+          if (!modifierKey) {
+            // See the note above (in the other branch of the if statement)
+            // about the NSShiftKeyMask, NSControlKeyMask, NSAlternateKeyMask
+            // and NSCommandKeyMask cases.
+            continue;
+          }
+          keyCode = modifierKey->keyCode;
+        }
+
+        // Remove flags
+        modifiers &= ~flag;
+        switch (keyCode) {
+          case kVK_Shift: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_RightShift);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSShiftKeyMask;
+            }
+            break;
+          }
+          case kVK_RightShift: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_Shift);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSShiftKeyMask;
+            }
+            break;
+          }
+          case kVK_Command: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_RightCommand);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSCommandKeyMask;
+            }
+            break;
+          }
+          case kVK_RightCommand: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_Command);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSCommandKeyMask;
+            }
+            break;
+          }
+          case kVK_Control: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_RightControl);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSControlKeyMask;
+            }
+            break;
+          }
+          case kVK_RightControl: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_Control);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSControlKeyMask;
+            }
+            break;
+          }
+          case kVK_Option: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_RightOption);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSAlternateKeyMask;
+            }
+            break;
+          }
+          case kVK_RightOption: {
+            const ModifierKey* modifierKey =
+              GetModifierKeyForNativeKeyCode(kVK_Option);
+            if (!modifierKey ||
+                !(modifiers & modifierKey->GetDeviceDependentFlags())) {
+              modifiers &= ~NSAlternateKeyMask;
+            }
+            break;
+          }
+          case kVK_Help:
+            modifiers &= ~NSHelpKeyMask;
+            break;
+          default:
+            break;
+        }
+
+        NSEvent* event =
+          [NSEvent keyEventWithType:NSFlagsChanged
+                           location:[aNativeEvent locationInWindow]
+                      modifierFlags:modifiers
+                          timestamp:[aNativeEvent timestamp]
+                       windowNumber:[aNativeEvent windowNumber]
+                            context:[aNativeEvent context]
+                         characters:@""
+        charactersIgnoringModifiers:@""
+                          isARepeat:NO
+                            keyCode:keyCode];
+        DispatchKeyEventForFlagsChanged(event, dispatchKeyDown);
+        if (Destroyed()) {
+          break;
+        }
+
+        // Stop if focus has changed.
+        // Check to see if mView is still the first responder.
+        if (![mView isFirstResponder]) {
+          break;
+        }
+
+      }
+      break;
+    }
+  }
+
+  // Be aware, the widget may have been destroyed.
+  sLastModifierState = [aNativeEvent modifierFlags];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+const TextInputHandler::ModifierKey*
+TextInputHandler::GetModifierKeyForNativeKeyCode(unsigned short aKeyCode) const
+{
+  for (ModifierKeyArray::index_type i = 0; i < mModifierKeys.Length(); ++i) {
+    if (mModifierKeys[i].keyCode == aKeyCode) {
+      return &((ModifierKey&)mModifierKeys[i]);
+    }
+  }
+  return nullptr;
+}
+
+const TextInputHandler::ModifierKey*
+TextInputHandler::GetModifierKeyForDeviceDependentFlags(NSUInteger aFlags) const
+{
+  for (ModifierKeyArray::index_type i = 0; i < mModifierKeys.Length(); ++i) {
+    if (mModifierKeys[i].GetDeviceDependentFlags() ==
+          (aFlags & ~NSDeviceIndependentModifierFlagsMask)) {
+      return &((ModifierKey&)mModifierKeys[i]);
+    }
+  }
+  return nullptr;
+}
+
+void
+TextInputHandler::DispatchKeyEventForFlagsChanged(NSEvent* aNativeEvent,
+                                                  bool aDispatchKeyDown)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (Destroyed()) {
+    return;
+  }
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::DispatchKeyEventForFlagsChanged, aNativeEvent=%p, "
+     "type=%s, keyCode=%s (0x%X), aDispatchKeyDown=%s, IsIMEComposing()=%s",
+     this, aNativeEvent, GetNativeKeyEventType(aNativeEvent),
+     GetKeyNameForNativeKeyCode([aNativeEvent keyCode]), [aNativeEvent keyCode],
+     TrueOrFalse(aDispatchKeyDown), TrueOrFalse(IsIMEComposing())));
+
+  if ([aNativeEvent type] != NSFlagsChanged || IsIMEComposing()) {
+    return;
+  }
+
+  nsresult rv = mDispatcher->BeginNativeInputTransaction();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+      MOZ_LOG(gLog, LogLevel::Error,
+        ("%p IMEInputHandler::DispatchKeyEventForFlagsChanged, "
+         "FAILED, due to BeginNativeInputTransaction() failure", this));
+    return;
+  }
+
+  EventMessage message = aDispatchKeyDown ? eKeyDown : eKeyUp;
+
+  // Fire a key event.
+  WidgetKeyboardEvent keyEvent(true, message, mWidget);
+  InitKeyEvent(aNativeEvent, keyEvent);
+
+  // Attach a plugin event, in case keyEvent gets dispatched to a plugin.  Only
+  // one field is needed -- the type.  The other fields can be constructed as
+  // the need arises.  But Gecko doesn't have anything equivalent to the
+  // NPCocoaEventFlagsChanged type, and this needs to be passed accurately to
+  // any plugin to which this event is sent.
+  NPCocoaEvent cocoaEvent;
+  nsCocoaUtils::InitNPCocoaEvent(&cocoaEvent);
+  cocoaEvent.type = NPCocoaEventFlagsChanged;
+  keyEvent.mPluginEvent.Copy(cocoaEvent);
+
+  KeyEventState currentKeyEvent(aNativeEvent);
+  nsEventStatus status = nsEventStatus_eIgnore;
+  mDispatcher->DispatchKeyboardEvent(message, keyEvent, status,
+                                     &currentKeyEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+TextInputHandler::InsertText(NSAttributedString* aAttrString,
+                             NSRange* aReplacementRange)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (Destroyed()) {
+    return;
+  }
+
+  KeyEventState* currentKeyEvent = GetCurrentKeyEvent();
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::InsertText, aAttrString=\"%s\", "
+     "aReplacementRange=%p { location=%llu, length=%llu }, "
+     "IsIMEComposing()=%s, IgnoreIMEComposition()=%s, "
+     "keyevent=%p, keydownHandled=%s, keypressDispatched=%s, "
+     "causedOtherKeyEvents=%s, compositionDispatched=%s",
+     this, GetCharacters([aAttrString string]), aReplacementRange,
+     aReplacementRange ? aReplacementRange->location : 0,
+     aReplacementRange ? aReplacementRange->length : 0,
+     TrueOrFalse(IsIMEComposing()), TrueOrFalse(IgnoreIMEComposition()),
+     currentKeyEvent ? currentKeyEvent->mKeyEvent : nullptr,
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mKeyDownHandled) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mKeyPressDispatched) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mCausedOtherKeyEvents) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mCompositionDispatched) : "N/A"));
+
+  if (IgnoreIMEComposition()) {
+    return;
+  }
+
+  InputContext context = mWidget->GetInputContext();
+  bool isEditable = (context.mIMEState.mEnabled == IMEState::ENABLED ||
+                     context.mIMEState.mEnabled == IMEState::PASSWORD);
+  NSRange selectedRange = SelectedRange();
+
+  nsAutoString str;
+  nsCocoaUtils::GetStringForNSString([aAttrString string], str);
+
+  AutoInsertStringClearer clearer(currentKeyEvent);
+  if (currentKeyEvent) {
+    currentKeyEvent->mInsertString = &str;
+  }
+
+  if (!IsIMEComposing() && str.IsEmpty()) {
+    // nothing to do if there is no content which can be removed.
+    if (!isEditable) {
+      return;
+    }
+    // If replacement range is specified, we need to remove the range.
+    // Otherwise, we need to remove the selected range if it's not collapsed.
+    if (aReplacementRange && aReplacementRange->location != NSNotFound) {
+      // nothing to do since the range is collapsed.
+      if (aReplacementRange->length == 0) {
+        return;
+      }
+      // If the replacement range is different from current selected range,
+      // select the range.
+      if (!NSEqualRanges(selectedRange, *aReplacementRange)) {
+        NS_ENSURE_TRUE_VOID(SetSelection(*aReplacementRange));
+      }
+      selectedRange = SelectedRange();
+    }
+    NS_ENSURE_TRUE_VOID(selectedRange.location != NSNotFound);
+    if (selectedRange.length == 0) {
+      return; // nothing to do
+    }
+    // If this is caused by a key input, the keypress event which will be
+    // dispatched later should cause the delete.  Therefore, nothing to do here.
+    // Although, we're not sure if such case is actually possible.
+    if (!currentKeyEvent) {
+      return;
+    }
+    // Delete the selected range.
+    RefPtr<TextInputHandler> kungFuDeathGrip(this);
+    WidgetContentCommandEvent deleteCommandEvent(true, eContentCommandDelete,
+                                                 mWidget);
+    DispatchEvent(deleteCommandEvent);
+    NS_ENSURE_TRUE_VOID(deleteCommandEvent.mSucceeded);
+    // Be aware! The widget might be destroyed here.
+    return;
+  }
+
+  bool isReplacingSpecifiedRange =
+    isEditable && aReplacementRange &&
+    aReplacementRange->location != NSNotFound &&
+    !NSEqualRanges(selectedRange, *aReplacementRange);
+
+  // If this is not caused by pressing a key, there is a composition or
+  // replacing a range which is different from current selection, let's
+  // insert the text as committing a composition.
+  // If InsertText() is called two or more times, we should insert all
+  // text with composition events.
+  // XXX When InsertText() is called multiple times, Chromium dispatches
+  //     only one composition event.  So, we need to store InsertText()
+  //     calls and flush later.
+  if (!currentKeyEvent || currentKeyEvent->mCompositionDispatched ||
+      IsIMEComposing() || isReplacingSpecifiedRange) {
+    InsertTextAsCommittingComposition(aAttrString, aReplacementRange);
+    if (currentKeyEvent) {
+      currentKeyEvent->mCompositionDispatched = true;
+    }
+    return;
+  }
+
+  // Don't let the same event be fired twice when hitting
+  // enter/return for Bug 420502.  However, Korean IME (or some other
+  // simple IME) may work without marked text.  For example, composing
+  // character may be inserted as committed text and it's modified with
+  // aReplacementRange.  When a keydown starts new composition with
+  // committing previous character, InsertText() may be called twice,
+  // one is for committing previous character and then, inserting new
+  // composing character as committed character.  In the latter case,
+  // |CanDispatchKeyPressEvent()| returns true but we need to dispatch
+  // keypress event for the new character.  So, when IME tries to insert
+  // printable characters, we should ignore current key event state even
+  // after the keydown has already caused dispatching composition event.
+  // XXX Anyway, we should sort out around this at fixing bug 1338460.
+  if (currentKeyEvent && !currentKeyEvent->CanDispatchKeyPressEvent() &&
+      (str.IsEmpty() || (str.Length() == 1 && !IsPrintableChar(str[0])))) {
+    return;
+  }
+
+  // XXX Shouldn't we hold mDispatcher instead of mWidget?
+  RefPtr<nsChildView> widget(mWidget);
+  nsresult rv = mDispatcher->BeginNativeInputTransaction();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+      MOZ_LOG(gLog, LogLevel::Error,
+        ("%p IMEInputHandler::HandleKeyUpEvent, "
+         "FAILED, due to BeginNativeInputTransaction() failure", this));
+    return;
+  }
+
+  // Dispatch keypress event with char instead of compositionchange event
+  WidgetKeyboardEvent keypressEvent(true, eKeyPress, widget);
+  // XXX Why do we need to dispatch keypress event for not inputting any
+  //     string?  If it wants to delete the specified range, should we
+  //     dispatch an eContentCommandDelete event instead?  Because this
+  //     must not be caused by a key operation, a part of IME's processing.
+  keypressEvent.mIsChar = IsPrintableChar(str.CharAt(0));
+
+  // Don't set other modifiers from the current event, because here in
+  // -insertText: they've already been taken into account in creating
+  // the input string.
+
+  if (currentKeyEvent) {
+    currentKeyEvent->InitKeyEvent(this, keypressEvent);
+  } else {
+    nsCocoaUtils::InitInputEvent(keypressEvent, static_cast<NSEvent*>(nullptr));
+    keypressEvent.mKeyNameIndex = KEY_NAME_INDEX_USE_STRING;
+    keypressEvent.mKeyValue = str;
+    // FYI: TextEventDispatcher will set mKeyCode to 0 for printable key's
+    //      keypress events even if they don't cause inputting non-empty string.
+  }
+
+  // Remove basic modifiers from keypress event because if they are included,
+  // nsPlaintextEditor ignores the event.
+  keypressEvent.mModifiers &= ~(MODIFIER_CONTROL |
+                                MODIFIER_ALT |
+                                MODIFIER_META);
+
+  // TODO:
+  // If mCurrentKeyEvent.mKeyEvent is null, the text should be inputted as
+  // composition events.
+  nsEventStatus status = nsEventStatus_eIgnore;
+  bool keyPressDispatched =
+    mDispatcher->MaybeDispatchKeypressEvents(keypressEvent, status,
+                                             currentKeyEvent);
+  bool keyPressHandled = (status == nsEventStatus_eConsumeNoDefault);
+
+  // Note: mWidget might have become null here. Don't count on it from here on.
+
+  if (currentKeyEvent) {
+    currentKeyEvent->mKeyPressHandled = keyPressHandled;
+    currentKeyEvent->mKeyPressDispatched = keyPressDispatched;
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+bool
+TextInputHandler::DoCommandBySelector(const char* aSelector)
+{
+  RefPtr<nsChildView> widget(mWidget);
+
+  KeyEventState* currentKeyEvent = GetCurrentKeyEvent();
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandler::DoCommandBySelector, aSelector=\"%s\", "
+     "Destroyed()=%s, keydownHandled=%s, keypressHandled=%s, "
+     "causedOtherKeyEvents=%s",
+     this, aSelector ? aSelector : "", TrueOrFalse(Destroyed()),
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mKeyDownHandled) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mKeyPressHandled) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mCausedOtherKeyEvents) : "N/A"));
+
+  if (currentKeyEvent && currentKeyEvent->CanDispatchKeyPressEvent()) {
+    nsresult rv = mDispatcher->BeginNativeInputTransaction();
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+        MOZ_LOG(gLog, LogLevel::Error,
+          ("%p IMEInputHandler::DoCommandBySelector, "
+           "FAILED, due to BeginNativeInputTransaction() failure "
+           "at dispatching keypress", this));
+      return false;
+    }
+
+    WidgetKeyboardEvent keypressEvent(true, eKeyPress, widget);
+    currentKeyEvent->InitKeyEvent(this, keypressEvent);
+
+    nsEventStatus status = nsEventStatus_eIgnore;
+    currentKeyEvent->mKeyPressDispatched =
+      mDispatcher->MaybeDispatchKeypressEvents(keypressEvent, status,
+                                               currentKeyEvent);
+    currentKeyEvent->mKeyPressHandled =
+      (status == nsEventStatus_eConsumeNoDefault);
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p TextInputHandler::DoCommandBySelector, keypress event "
+       "dispatched, Destroyed()=%s, keypressHandled=%s",
+       this, TrueOrFalse(Destroyed()),
+       TrueOrFalse(currentKeyEvent->mKeyPressHandled)));
+  }
+
+  return (!Destroyed() && currentKeyEvent &&
+          currentKeyEvent->IsDefaultPrevented());
+}
+
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  IMEInputHandler implementation (static methods)
+ *
+ ******************************************************************************/
+
+bool IMEInputHandler::sStaticMembersInitialized = false;
+bool IMEInputHandler::sCachedIsForRTLLangage = false;
+CFStringRef IMEInputHandler::sLatestIMEOpenedModeInputSourceID = nullptr;
+IMEInputHandler* IMEInputHandler::sFocusedIMEHandler = nullptr;
+
+// static
+void
+IMEInputHandler::InitStaticMembers()
+{
+  if (sStaticMembersInitialized)
+    return;
+  sStaticMembersInitialized = true;
+  // We need to check the keyboard layout changes on all applications.
+  CFNotificationCenterRef center = ::CFNotificationCenterGetDistributedCenter();
+  // XXX Don't we need to remove the observer at shut down?
+  // Mac Dev Center's document doesn't say how to remove the observer if
+  // the second parameter is NULL.
+  ::CFNotificationCenterAddObserver(center, NULL,
+      OnCurrentTextInputSourceChange,
+      kTISNotifySelectedKeyboardInputSourceChanged, NULL,
+      CFNotificationSuspensionBehaviorDeliverImmediately);
+  // Initiailize with the current keyboard layout
+  OnCurrentTextInputSourceChange(NULL, NULL,
+                                 kTISNotifySelectedKeyboardInputSourceChanged,
+                                 NULL, NULL);
+}
+
+// static
+void
+IMEInputHandler::OnCurrentTextInputSourceChange(CFNotificationCenterRef aCenter,
+                                                void* aObserver,
+                                                CFStringRef aName,
+                                                const void* aObject,
+                                                CFDictionaryRef aUserInfo)
+{
+  // Cache the latest IME opened mode to sLatestIMEOpenedModeInputSourceID.
+  TISInputSourceWrapper tis;
+  tis.InitByCurrentInputSource();
+  if (tis.IsOpenedIMEMode()) {
+    tis.GetInputSourceID(sLatestIMEOpenedModeInputSourceID);
+  }
+
+  if (MOZ_LOG_TEST(gLog, LogLevel::Info)) {
+    static CFStringRef sLastTIS = nullptr;
+    CFStringRef newTIS;
+    tis.GetInputSourceID(newTIS);
+    if (!sLastTIS ||
+        ::CFStringCompare(sLastTIS, newTIS, 0) != kCFCompareEqualTo) {
+      TISInputSourceWrapper tis1, tis2, tis3, tis4, tis5;
+      tis1.InitByCurrentKeyboardLayout();
+      tis2.InitByCurrentASCIICapableInputSource();
+      tis3.InitByCurrentASCIICapableKeyboardLayout();
+      tis4.InitByCurrentInputMethodKeyboardLayoutOverride();
+      tis5.InitByTISInputSourceRef(tis.GetKeyboardLayoutInputSource());
+      CFStringRef is0 = nullptr, is1 = nullptr, is2 = nullptr, is3 = nullptr,
+                  is4 = nullptr, is5 = nullptr, type0 = nullptr,
+                  lang0 = nullptr, bundleID0 = nullptr;
+      tis.GetInputSourceID(is0);
+      tis1.GetInputSourceID(is1);
+      tis2.GetInputSourceID(is2);
+      tis3.GetInputSourceID(is3);
+      tis4.GetInputSourceID(is4);
+      tis5.GetInputSourceID(is5);
+      tis.GetInputSourceType(type0);
+      tis.GetPrimaryLanguage(lang0);
+      tis.GetBundleID(bundleID0);
+
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("IMEInputHandler::OnCurrentTextInputSourceChange,\n"
+         "  Current Input Source is changed to:\n"
+         "    currentInputContext=%p\n"
+         "    %s\n"
+         "      type=%s %s\n"
+         "      overridden keyboard layout=%s\n"
+         "      used keyboard layout for translation=%s\n"
+         "    primary language=%s\n"
+         "    bundle ID=%s\n"
+         "    current ASCII capable Input Source=%s\n"
+         "    current Keyboard Layout=%s\n"
+         "    current ASCII capable Keyboard Layout=%s",
+         [NSTextInputContext currentInputContext], GetCharacters(is0),
+         GetCharacters(type0), tis.IsASCIICapable() ? "- ASCII capable " : "",
+         GetCharacters(is4), GetCharacters(is5),
+         GetCharacters(lang0), GetCharacters(bundleID0),
+         GetCharacters(is2), GetCharacters(is1), GetCharacters(is3)));
+    }
+    sLastTIS = newTIS;
+  }
+
+  /**
+   * When the direction is changed, all the children are notified.
+   * No need to treat the initial case separately because it is covered
+   * by the general case (sCachedIsForRTLLangage is initially false)
+   */
+  if (sCachedIsForRTLLangage != tis.IsForRTLLanguage()) {
+    WidgetUtils::SendBidiKeyboardInfoToContent();
+    sCachedIsForRTLLangage = tis.IsForRTLLanguage();
+  }
+}
+
+// static
+void
+IMEInputHandler::FlushPendingMethods(nsITimer* aTimer, void* aClosure)
+{
+  NS_ASSERTION(aClosure, "aClosure is null");
+  static_cast<IMEInputHandler*>(aClosure)->ExecutePendingMethods();
+}
+
+// static
+CFArrayRef
+IMEInputHandler::CreateAllIMEModeList()
+{
+  const void* keys[] = { kTISPropertyInputSourceType };
+  const void* values[] = { kTISTypeKeyboardInputMode };
+  CFDictionaryRef filter =
+    ::CFDictionaryCreate(kCFAllocatorDefault, keys, values, 1, NULL, NULL);
+  NS_ASSERTION(filter, "failed to create the filter");
+  CFArrayRef list = ::TISCreateInputSourceList(filter, true);
+  ::CFRelease(filter);
+  return list;
+}
+
+// static
+void
+IMEInputHandler::DebugPrintAllIMEModes()
+{
+  if (MOZ_LOG_TEST(gLog, LogLevel::Info)) {
+    CFArrayRef list = CreateAllIMEModeList();
+    MOZ_LOG(gLog, LogLevel::Info, ("IME mode configuration:"));
+    CFIndex idx = ::CFArrayGetCount(list);
+    TISInputSourceWrapper tis;
+    for (CFIndex i = 0; i < idx; ++i) {
+      TISInputSourceRef inputSource = static_cast<TISInputSourceRef>(
+        const_cast<void *>(::CFArrayGetValueAtIndex(list, i)));
+      tis.InitByTISInputSourceRef(inputSource);
+      nsAutoString name, isid;
+      tis.GetLocalizedName(name);
+      tis.GetInputSourceID(isid);
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("  %s\t<%s>%s%s\n",
+         NS_ConvertUTF16toUTF8(name).get(),
+         NS_ConvertUTF16toUTF8(isid).get(),
+         tis.IsASCIICapable() ? "" : "\t(Isn't ASCII capable)",
+         tis.IsEnabled() ? "" : "\t(Isn't Enabled)"));
+    }
+    ::CFRelease(list);
+  }
+}
+
+//static
+TSMDocumentID
+IMEInputHandler::GetCurrentTSMDocumentID()
+{
+  // At least on Mac OS X 10.6.x and 10.7.x, ::TSMGetActiveDocument() has a bug.
+  // The result of ::TSMGetActiveDocument() isn't modified for new active text
+  // input context until [NSTextInputContext currentInputContext] is called.
+  // Therefore, we need to call it here.
+  [NSTextInputContext currentInputContext];
+  return ::TSMGetActiveDocument();
+}
+
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  IMEInputHandler implementation #1
+ *    The methods are releated to the pending methods.  Some jobs should be
+ *    run after the stack is finished, e.g, some methods cannot run the jobs
+ *    during processing the focus event.  And also some other jobs should be
+ *    run at the next focus event is processed.
+ *    The pending methods are recorded in mPendingMethods.  They are executed
+ *    by ExecutePendingMethods via FlushPendingMethods.
+ *
+ ******************************************************************************/
+
+NS_IMETHODIMP
+IMEInputHandler::NotifyIME(TextEventDispatcher* aTextEventDispatcher,
+                           const IMENotification& aNotification)
+{
+  switch (aNotification.mMessage) {
+    case REQUEST_TO_COMMIT_COMPOSITION:
+      CommitIMEComposition();
+      return NS_OK;
+    case REQUEST_TO_CANCEL_COMPOSITION:
+      CancelIMEComposition();
+      return NS_OK;
+    case NOTIFY_IME_OF_FOCUS:
+      if (IsFocused()) {
+        nsIWidget* widget = aTextEventDispatcher->GetWidget();
+        if (widget && widget->GetInputContext().IsPasswordEditor()) {
+          EnableSecureEventInput();
+        } else {
+          EnsureSecureEventInputDisabled();
+        }
+      }
+      OnFocusChangeInGecko(true);
+      return NS_OK;
+    case NOTIFY_IME_OF_BLUR:
+      OnFocusChangeInGecko(false);
+      return NS_OK;
+    case NOTIFY_IME_OF_SELECTION_CHANGE:
+      OnSelectionChange(aNotification);
+      return NS_OK;
+    default:
+      return NS_ERROR_NOT_IMPLEMENTED;
+  }
+}
+
+NS_IMETHODIMP_(void)
+IMEInputHandler::OnRemovedFrom(TextEventDispatcher* aTextEventDispatcher)
+{
+  // XXX When input transaction is being stolen by add-on, what should we do?
+}
+
+NS_IMETHODIMP_(void)
+IMEInputHandler::WillDispatchKeyboardEvent(
+                   TextEventDispatcher* aTextEventDispatcher,
+                   WidgetKeyboardEvent& aKeyboardEvent,
+                   uint32_t aIndexOfKeypress,
+                   void* aData)
+{
+  // If the keyboard event is not caused by a native key event, we can do
+  // nothing here.
+  if (!aData) {
+    return;
+  }
+
+  KeyEventState* currentKeyEvent = static_cast<KeyEventState*>(aData);
+  NSEvent* nativeEvent = currentKeyEvent->mKeyEvent;
+  nsAString* insertString = currentKeyEvent->mInsertString;
+  if (KeyboardLayoutOverrideRef().mOverrideEnabled) {
+    TISInputSourceWrapper tis;
+    tis.InitByLayoutID(KeyboardLayoutOverrideRef().mKeyboardLayout, true);
+    tis.WillDispatchKeyboardEvent(nativeEvent, insertString, aKeyboardEvent);
+    return;
+  }
+  TISInputSourceWrapper::CurrentInputSource().
+    WillDispatchKeyboardEvent(nativeEvent, insertString, aKeyboardEvent);
+}
+
+void
+IMEInputHandler::NotifyIMEOfFocusChangeInGecko()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::NotifyIMEOfFocusChangeInGecko, "
+     "Destroyed()=%s, IsFocused()=%s, inputContext=%p",
+     this, TrueOrFalse(Destroyed()), TrueOrFalse(IsFocused()),
+     mView ? [mView inputContext] : nullptr));
+
+  if (Destroyed()) {
+    return;
+  }
+
+  if (!IsFocused()) {
+    // retry at next focus event
+    mPendingMethods |= kNotifyIMEOfFocusChangeInGecko;
+    return;
+  }
+
+  MOZ_ASSERT(mView);
+  NSTextInputContext* inputContext = [mView inputContext];
+  NS_ENSURE_TRUE_VOID(inputContext);
+
+  // When an <input> element on a XUL <panel> element gets focus from an <input>
+  // element on the opener window of the <panel> element, the owner window
+  // still has native focus.  Therefore, IMEs may store the opener window's
+  // level at this time because they don't know the actual focus is moved to
+  // different window.  If IMEs try to get the newest window level after the
+  // focus change, we return the window level of the XUL <panel>'s widget.
+  // Therefore, let's emulate the native focus change.  Then, IMEs can refresh
+  // the stored window level.
+  [inputContext deactivate];
+  [inputContext activate];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+IMEInputHandler::DiscardIMEComposition()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::DiscardIMEComposition, "
+     "Destroyed()=%s, IsFocused()=%s, mView=%p, inputContext=%p",
+     this, TrueOrFalse(Destroyed()), TrueOrFalse(IsFocused()),
+     mView, mView ? [mView inputContext] : nullptr));
+
+  if (Destroyed()) {
+    return;
+  }
+
+  if (!IsFocused()) {
+    // retry at next focus event
+    mPendingMethods |= kDiscardIMEComposition;
+    return;
+  }
+
+  NS_ENSURE_TRUE_VOID(mView);
+  NSTextInputContext* inputContext = [mView inputContext];
+  NS_ENSURE_TRUE_VOID(inputContext);
+  mIgnoreIMECommit = true;
+  [inputContext discardMarkedText];
+  mIgnoreIMECommit = false;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK
+}
+
+void
+IMEInputHandler::SyncASCIICapableOnly()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::SyncASCIICapableOnly, "
+     "Destroyed()=%s, IsFocused()=%s, mIsASCIICapableOnly=%s, "
+     "GetCurrentTSMDocumentID()=%p",
+     this, TrueOrFalse(Destroyed()), TrueOrFalse(IsFocused()),
+     TrueOrFalse(mIsASCIICapableOnly), GetCurrentTSMDocumentID()));
+
+  if (Destroyed()) {
+    return;
+  }
+
+  if (!IsFocused()) {
+    // retry at next focus event
+    mPendingMethods |= kSyncASCIICapableOnly;
+    return;
+  }
+
+  TSMDocumentID doc = GetCurrentTSMDocumentID();
+  if (!doc) {
+    // retry
+    mPendingMethods |= kSyncASCIICapableOnly;
+    NS_WARNING("Application is active but there is no active document");
+    ResetTimer();
+    return;
+  }
+
+  if (mIsASCIICapableOnly) {
+    CFArrayRef ASCIICapableTISList = ::TISCreateASCIICapableInputSourceList();
+    ::TSMSetDocumentProperty(doc,
+                             kTSMDocumentEnabledInputSourcesPropertyTag,
+                             sizeof(CFArrayRef),
+                             &ASCIICapableTISList);
+    ::CFRelease(ASCIICapableTISList);
+  } else {
+    ::TSMRemoveDocumentProperty(doc,
+                                kTSMDocumentEnabledInputSourcesPropertyTag);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+IMEInputHandler::ResetTimer()
+{
+  NS_ASSERTION(mPendingMethods != 0,
+               "There are not pending methods, why this is called?");
+  if (mTimer) {
+    mTimer->Cancel();
+  } else {
+    mTimer = do_CreateInstance(NS_TIMER_CONTRACTID);
+    NS_ENSURE_TRUE(mTimer, );
+  }
+  mTimer->InitWithFuncCallback(FlushPendingMethods, this, 0,
+                               nsITimer::TYPE_ONE_SHOT);
+}
+
+void
+IMEInputHandler::ExecutePendingMethods()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mTimer) {
+    mTimer->Cancel();
+    mTimer = nullptr;
+  }
+
+  if (![[NSApplication sharedApplication] isActive]) {
+    mIsInFocusProcessing = false;
+    // If we're not active, we should retry at focus event
+    return;
+  }
+
+  uint32_t pendingMethods = mPendingMethods;
+  // First, reset the pending method flags because if each methods cannot
+  // run now, they can reentry to the pending flags by theirselves.
+  mPendingMethods = 0;
+
+  if (pendingMethods & kDiscardIMEComposition)
+    DiscardIMEComposition();
+  if (pendingMethods & kSyncASCIICapableOnly)
+    SyncASCIICapableOnly();
+  if (pendingMethods & kNotifyIMEOfFocusChangeInGecko) {
+    NotifyIMEOfFocusChangeInGecko();
+  }
+
+  mIsInFocusProcessing = false;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ * IMEInputHandler implementation (native event handlers)
+ *
+ ******************************************************************************/
+
+TextRangeType
+IMEInputHandler::ConvertToTextRangeType(uint32_t aUnderlineStyle,
+                                        NSRange& aSelectedRange)
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::ConvertToTextRangeType, "
+     "aUnderlineStyle=%llu, aSelectedRange.length=%llu,",
+     this, aUnderlineStyle, aSelectedRange.length));
+
+  // We assume that aUnderlineStyle is NSUnderlineStyleSingle or
+  // NSUnderlineStyleThick.  NSUnderlineStyleThick should indicate a selected
+  // clause.  Otherwise, should indicate non-selected clause.
+
+  if (aSelectedRange.length == 0) {
+    switch (aUnderlineStyle) {
+      case NSUnderlineStyleSingle:
+        return TextRangeType::eRawClause;
+      case NSUnderlineStyleThick:
+        return TextRangeType::eSelectedRawClause;
+      default:
+        NS_WARNING("Unexpected line style");
+        return TextRangeType::eSelectedRawClause;
+    }
+  }
+
+  switch (aUnderlineStyle) {
+    case NSUnderlineStyleSingle:
+      return TextRangeType::eConvertedClause;
+    case NSUnderlineStyleThick:
+      return TextRangeType::eSelectedClause;
+    default:
+      NS_WARNING("Unexpected line style");
+      return TextRangeType::eSelectedClause;
+  }
+}
+
+uint32_t
+IMEInputHandler::GetRangeCount(NSAttributedString *aAttrString)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  // Iterate through aAttrString for the NSUnderlineStyleAttributeName and
+  // count the different segments adjusting limitRange as we go.
+  uint32_t count = 0;
+  NSRange effectiveRange;
+  NSRange limitRange = NSMakeRange(0, [aAttrString length]);
+  while (limitRange.length > 0) {
+    [aAttrString  attribute:NSUnderlineStyleAttributeName 
+                    atIndex:limitRange.location 
+      longestEffectiveRange:&effectiveRange
+                    inRange:limitRange];
+    limitRange =
+      NSMakeRange(NSMaxRange(effectiveRange), 
+                  NSMaxRange(limitRange) - NSMaxRange(effectiveRange));
+    count++;
+  }
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::GetRangeCount, aAttrString=\"%s\", count=%llu",
+     this, GetCharacters([aAttrString string]), count));
+
+  return count;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0);
+}
+
+already_AddRefed<mozilla::TextRangeArray>
+IMEInputHandler::CreateTextRangeArray(NSAttributedString *aAttrString,
+                                      NSRange& aSelectedRange)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  RefPtr<mozilla::TextRangeArray> textRangeArray =
+                                      new mozilla::TextRangeArray();
+
+  // Note that we shouldn't append ranges when composition string
+  // is empty because it may cause TextComposition confused.
+  if (![aAttrString length]) {
+    return textRangeArray.forget();
+  }
+
+  // Convert the Cocoa range into the TextRange Array used in Gecko.
+  // Iterate through the attributed string and map the underline attribute to
+  // Gecko IME textrange attributes.  We may need to change the code here if
+  // we change the implementation of validAttributesForMarkedText.
+  NSRange limitRange = NSMakeRange(0, [aAttrString length]);
+  uint32_t rangeCount = GetRangeCount(aAttrString);
+  for (uint32_t i = 0; i < rangeCount && limitRange.length > 0; i++) {
+    NSRange effectiveRange;
+    id attributeValue = [aAttrString attribute:NSUnderlineStyleAttributeName
+                                       atIndex:limitRange.location
+                         longestEffectiveRange:&effectiveRange
+                                       inRange:limitRange];
+
+    TextRange range;
+    range.mStartOffset = effectiveRange.location;
+    range.mEndOffset = NSMaxRange(effectiveRange);
+    range.mRangeType =
+      ConvertToTextRangeType([attributeValue intValue], aSelectedRange);
+    textRangeArray->AppendElement(range);
+
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::CreateTextRangeArray, "
+       "range={ mStartOffset=%llu, mEndOffset=%llu, mRangeType=%s }",
+       this, range.mStartOffset, range.mEndOffset,
+       ToChar(range.mRangeType)));
+
+    limitRange =
+      NSMakeRange(NSMaxRange(effectiveRange), 
+                  NSMaxRange(limitRange) - NSMaxRange(effectiveRange));
+  }
+
+  // Get current caret position.
+  TextRange range;
+  range.mStartOffset = aSelectedRange.location + aSelectedRange.length;
+  range.mEndOffset = range.mStartOffset;
+  range.mRangeType = TextRangeType::eCaret;
+  textRangeArray->AppendElement(range);
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::CreateTextRangeArray, "
+     "range={ mStartOffset=%llu, mEndOffset=%llu, mRangeType=%s }",
+     this, range.mStartOffset, range.mEndOffset,
+     ToChar(range.mRangeType)));
+
+  return textRangeArray.forget();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSNULL;
+}
+
+bool
+IMEInputHandler::DispatchCompositionStartEvent()
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::DispatchCompositionStartEvent, "
+     "mSelectedRange={ location=%llu, length=%llu }, Destroyed()=%s, "
+     "mView=%p, mWidget=%p, inputContext=%p, mIsIMEComposing=%s",
+     this,  SelectedRange().location, mSelectedRange.length,
+     TrueOrFalse(Destroyed()), mView, mWidget,
+     mView ? [mView inputContext] : nullptr, TrueOrFalse(mIsIMEComposing)));
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  nsresult rv = mDispatcher->BeginNativeInputTransaction();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    MOZ_LOG(gLog, LogLevel::Error,
+      ("%p IMEInputHandler::DispatchCompositionStartEvent, "
+       "FAILED, due to BeginNativeInputTransaction() failure", this));
+    return false;
+  }
+
+  NS_ASSERTION(!mIsIMEComposing, "There is a composition already");
+  mIsIMEComposing = true;
+
+  nsEventStatus status;
+  rv = mDispatcher->StartComposition(status);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    MOZ_LOG(gLog, LogLevel::Error,
+      ("%p IMEInputHandler::DispatchCompositionStartEvent, "
+       "FAILED, due to StartComposition() failure", this));
+    return false;
+  }
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::DispatchCompositionStartEvent, "
+       "destroyed by compositionstart event", this));
+    return false;
+  }
+
+  // FYI: compositionstart may cause committing composition by the webapp.
+  if (!mIsIMEComposing) {
+    return false;
+  }
+
+  // FYI: The selection range might have been modified by a compositionstart
+  //      event handler.
+  mIMECompositionStart = SelectedRange().location;
+  return true;
+}
+
+bool
+IMEInputHandler::DispatchCompositionChangeEvent(const nsString& aText,
+                                                NSAttributedString* aAttrString,
+                                                NSRange& aSelectedRange)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::DispatchCompositionChangeEvent, "
+     "aText=\"%s\", aAttrString=\"%s\", "
+     "aSelectedRange={ location=%llu, length=%llu }, Destroyed()=%s, mView=%p, "
+     "mWidget=%p, inputContext=%p, mIsIMEComposing=%s",
+     this, NS_ConvertUTF16toUTF8(aText).get(),
+     GetCharacters([aAttrString string]),
+     aSelectedRange.location, aSelectedRange.length,
+     TrueOrFalse(Destroyed()), mView, mWidget,
+     mView ? [mView inputContext] : nullptr, TrueOrFalse(mIsIMEComposing)));
+
+  NS_ENSURE_TRUE(!Destroyed(), false);
+
+  NS_ASSERTION(mIsIMEComposing, "We're not in composition");
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  nsresult rv = mDispatcher->BeginNativeInputTransaction();
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    MOZ_LOG(gLog, LogLevel::Error,
+      ("%p IMEInputHandler::DispatchCompositionChangeEvent, "
+       "FAILED, due to BeginNativeInputTransaction() failure", this));
+    return false;
+  }
+
+  RefPtr<TextRangeArray> rangeArray =
+    CreateTextRangeArray(aAttrString, aSelectedRange);
+
+  rv = mDispatcher->SetPendingComposition(aText, rangeArray);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    MOZ_LOG(gLog, LogLevel::Error,
+      ("%p IMEInputHandler::DispatchCompositionChangeEvent, "
+       "FAILED, due to SetPendingComposition() failure", this));
+    return false;
+  }
+
+  mSelectedRange.location = mIMECompositionStart + aSelectedRange.location;
+  mSelectedRange.length = aSelectedRange.length;
+
+  if (mIMECompositionString) {
+    [mIMECompositionString release];
+  }
+  mIMECompositionString = [[aAttrString string] retain];
+
+  nsEventStatus status;
+  rv = mDispatcher->FlushPendingComposition(status);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    MOZ_LOG(gLog, LogLevel::Error,
+      ("%p IMEInputHandler::DispatchCompositionChangeEvent, "
+       "FAILED, due to FlushPendingComposition() failure", this));
+    return false;
+  }
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::DispatchCompositionChangeEvent, "
+       "destroyed by compositionchange event", this));
+    return false;
+  }
+
+  // FYI: compositionstart may cause committing composition by the webapp.
+  return mIsIMEComposing;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+bool
+IMEInputHandler::DispatchCompositionCommitEvent(const nsAString* aCommitString)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::DispatchCompositionCommitEvent, "
+     "aCommitString=0x%p (\"%s\"), Destroyed()=%s, mView=%p, mWidget=%p, "
+     "inputContext=%p, mIsIMEComposing=%s",
+     this, aCommitString,
+     aCommitString ? NS_ConvertUTF16toUTF8(*aCommitString).get() : "",
+     TrueOrFalse(Destroyed()), mView, mWidget,
+     mView ? [mView inputContext] : nullptr, TrueOrFalse(mIsIMEComposing)));
+
+  NS_ASSERTION(mIsIMEComposing, "We're not in composition");
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  if (!Destroyed()) {
+    // IME may query selection immediately after this, however, in e10s mode,
+    // OnSelectionChange() will be called asynchronously.  Until then, we
+    // should emulate expected selection range if the webapp does nothing.
+    mSelectedRange.location = mIMECompositionStart;
+    if (aCommitString) {
+      mSelectedRange.location += aCommitString->Length();
+    } else if (mIMECompositionString) {
+      nsAutoString commitString;
+      nsCocoaUtils::GetStringForNSString(mIMECompositionString, commitString);
+      mSelectedRange.location += commitString.Length();
+    }
+    mSelectedRange.length = 0;
+
+    nsresult rv = mDispatcher->BeginNativeInputTransaction();
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      MOZ_LOG(gLog, LogLevel::Error,
+        ("%p IMEInputHandler::DispatchCompositionCommitEvent, "
+         "FAILED, due to BeginNativeInputTransaction() failure", this));
+    } else {
+      nsEventStatus status;
+      rv = mDispatcher->CommitComposition(status, aCommitString);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        MOZ_LOG(gLog, LogLevel::Error,
+          ("%p IMEInputHandler::DispatchCompositionCommitEvent, "
+           "FAILED, due to BeginNativeInputTransaction() failure", this));
+      }
+    }
+  }
+
+  mIsIMEComposing = false;
+  mIMECompositionStart = UINT32_MAX;
+  if (mIMECompositionString) {
+    [mIMECompositionString release];
+    mIMECompositionString = nullptr;
+  }
+
+  if (Destroyed()) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::DispatchCompositionCommitEvent, "
+       "destroyed by compositioncommit event", this));
+    return false;
+  }
+
+  return true;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+void
+IMEInputHandler::InsertTextAsCommittingComposition(
+                   NSAttributedString* aAttrString,
+                   NSRange* aReplacementRange)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::InsertTextAsCommittingComposition, "
+     "aAttrString=\"%s\", aReplacementRange=%p { location=%llu, length=%llu }, "
+     "Destroyed()=%s, IsIMEComposing()=%s, "
+     "mMarkedRange={ location=%llu, length=%llu }",
+     this, GetCharacters([aAttrString string]), aReplacementRange,
+     aReplacementRange ? aReplacementRange->location : 0,
+     aReplacementRange ? aReplacementRange->length : 0,
+     TrueOrFalse(Destroyed()), TrueOrFalse(IsIMEComposing()),
+     mMarkedRange.location, mMarkedRange.length));
+
+  if (IgnoreIMECommit()) {
+    MOZ_CRASH("IMEInputHandler::InsertTextAsCommittingComposition() must not"
+              "be called while canceling the composition");
+  }
+
+  if (Destroyed()) {
+    return;
+  }
+
+  // First, commit current composition with the latest composition string if the
+  // replacement range is different from marked range.
+  if (IsIMEComposing() && aReplacementRange &&
+      aReplacementRange->location != NSNotFound &&
+      !NSEqualRanges(MarkedRange(), *aReplacementRange)) {
+    if (!DispatchCompositionCommitEvent()) {
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("%p IMEInputHandler::InsertTextAsCommittingComposition, "
+         "destroyed by commiting composition for setting replacement range",
+         this));
+      return;
+    }
+  }
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  nsString str;
+  nsCocoaUtils::GetStringForNSString([aAttrString string], str);
+
+  if (!IsIMEComposing()) {
+    // If there is no selection and replacement range is specified, set the
+    // range as selection.
+    if (aReplacementRange && aReplacementRange->location != NSNotFound &&
+        !NSEqualRanges(SelectedRange(), *aReplacementRange)) {
+      NS_ENSURE_TRUE_VOID(SetSelection(*aReplacementRange));
+    }
+
+    if (!DispatchCompositionStartEvent()) {
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("%p IMEInputHandler::InsertTextAsCommittingComposition, "
+         "cannot continue handling composition after compositionstart", this));
+      return;
+    }
+  }
+
+  if (!DispatchCompositionCommitEvent(&str)) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::InsertTextAsCommittingComposition, "
+       "destroyed by compositioncommit event", this));
+    return;
+  }
+
+  mMarkedRange = NSMakeRange(NSNotFound, 0);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+IMEInputHandler::SetMarkedText(NSAttributedString* aAttrString,
+                               NSRange& aSelectedRange,
+                               NSRange* aReplacementRange)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  KeyEventState* currentKeyEvent = GetCurrentKeyEvent();
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::SetMarkedText, "
+     "aAttrString=\"%s\", aSelectedRange={ location=%llu, length=%llu }, "
+     "aReplacementRange=%p { location=%llu, length=%llu }, "
+     "Destroyed()=%s, IgnoreIMEComposition()=%s, IsIMEComposing()=%s, "
+     "mMarkedRange={ location=%llu, length=%llu }, keyevent=%p, "
+     "keydownHandled=%s, keypressDispatched=%s, causedOtherKeyEvents=%s, "
+     "compositionDispatched=%s",
+     this, GetCharacters([aAttrString string]),
+     aSelectedRange.location, aSelectedRange.length, aReplacementRange,
+     aReplacementRange ? aReplacementRange->location : 0,
+     aReplacementRange ? aReplacementRange->length : 0,
+     TrueOrFalse(Destroyed()), TrueOrFalse(IgnoreIMEComposition()),
+     TrueOrFalse(IsIMEComposing()),
+     mMarkedRange.location, mMarkedRange.length,
+     currentKeyEvent ? currentKeyEvent->mKeyEvent : nullptr,
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mKeyDownHandled) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mKeyPressDispatched) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mCausedOtherKeyEvents) : "N/A",
+     currentKeyEvent ?
+       TrueOrFalse(currentKeyEvent->mCompositionDispatched) : "N/A"));
+
+  // If SetMarkedText() is called during handling a key press, that means that
+  // the key event caused this composition.  So, keypress event shouldn't
+  // be dispatched later, let's mark the key event causing composition event.
+  if (currentKeyEvent) {
+    currentKeyEvent->mCompositionDispatched = true;
+  }
+
+  if (Destroyed() || IgnoreIMEComposition()) {
+    return;
+  }
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  // First, commit current composition with the latest composition string if the
+  // replacement range is different from marked range.
+  if (IsIMEComposing() && aReplacementRange &&
+      aReplacementRange->location != NSNotFound &&
+      !NSEqualRanges(MarkedRange(), *aReplacementRange)) {
+    AutoRestore<bool> ignoreIMECommit(mIgnoreIMECommit);
+    mIgnoreIMECommit = false;
+    if (!DispatchCompositionCommitEvent()) {
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("%p IMEInputHandler::SetMarkedText, "
+         "destroyed by commiting composition for setting replacement range",
+         this));
+      return;
+    }
+  }
+
+  nsString str;
+  nsCocoaUtils::GetStringForNSString([aAttrString string], str);
+
+  mMarkedRange.length = str.Length();
+
+  if (!IsIMEComposing() && !str.IsEmpty()) {
+    // If there is no selection and replacement range is specified, set the
+    // range as selection.
+    if (aReplacementRange && aReplacementRange->location != NSNotFound &&
+        !NSEqualRanges(SelectedRange(), *aReplacementRange)) {
+      NS_ENSURE_TRUE_VOID(SetSelection(*aReplacementRange));
+    }
+
+    mMarkedRange.location = SelectedRange().location;
+
+    if (!DispatchCompositionStartEvent()) {
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("%p IMEInputHandler::SetMarkedText, cannot continue handling "
+         "composition after dispatching compositionstart", this));
+      return;
+    }
+  }
+
+  if (!str.IsEmpty()) {
+    if (!DispatchCompositionChangeEvent(str, aAttrString, aSelectedRange)) {
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("%p IMEInputHandler::SetMarkedText, cannot continue handling "
+         "composition after dispatching compositionchange", this));
+    }
+    return;
+  }
+
+  // If the composition string becomes empty string, we should commit
+  // current composition.
+  if (!DispatchCompositionCommitEvent(&EmptyString())) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::SetMarkedText, "
+       "destroyed by compositioncommit event", this));
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NSAttributedString*
+IMEInputHandler::GetAttributedSubstringFromRange(NSRange& aRange,
+                                                 NSRange* aActualRange)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::GetAttributedSubstringFromRange, "
+     "aRange={ location=%llu, length=%llu }, aActualRange=%p, Destroyed()=%s",
+     this, aRange.location, aRange.length, aActualRange,
+     TrueOrFalse(Destroyed())));
+
+  if (aActualRange) {
+    *aActualRange = NSMakeRange(NSNotFound, 0);
+  }
+
+  if (Destroyed() || aRange.location == NSNotFound || aRange.length == 0) {
+    return nil;
+  }
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  // If we're in composing, the queried range may be in the composition string.
+  // In such case, we should use mIMECompositionString since if the composition
+  // string is handled by a remote process, the content cache may be out of
+  // date.
+  // XXX Should we set composition string attributes?  Although, Blink claims
+  //     that some attributes of marked text are supported, but they return
+  //     just marked string without any style.  So, let's keep current behavior
+  //     at least for now.
+  NSUInteger compositionLength =
+    mIMECompositionString ? [mIMECompositionString length] : 0;
+  if (mIMECompositionStart != UINT32_MAX &&
+      mIMECompositionStart >= aRange.location &&
+      mIMECompositionStart + compositionLength <=
+        aRange.location + aRange.length) {
+    NSRange range =
+      NSMakeRange(aRange.location - mIMECompositionStart, aRange.length);
+    NSString* nsstr = [mIMECompositionString substringWithRange:range];
+    NSMutableAttributedString* result =
+      [[[NSMutableAttributedString alloc] initWithString:nsstr
+                                              attributes:nil] autorelease];
+    // XXX We cannot return font information in this case.  However, this
+    //     case must occur only when IME tries to confirm if composing string
+    //     is handled as expected.
+    if (aActualRange) {
+      *aActualRange = aRange;
+    }
+
+    if (MOZ_LOG_TEST(gLog, LogLevel::Info)) {
+      nsAutoString str;
+      nsCocoaUtils::GetStringForNSString(nsstr, str);
+      MOZ_LOG(gLog, LogLevel::Info,
+        ("%p IMEInputHandler::GetAttributedSubstringFromRange, "
+         "computed with mIMECompositionString (result string=\"%s\")",
+         this, NS_ConvertUTF16toUTF8(str).get()));
+    }
+    return result;
+  }
+
+  nsAutoString str;
+  WidgetQueryContentEvent textContent(true, eQueryTextContent, mWidget);
+  WidgetQueryContentEvent::Options options;
+  int64_t startOffset = aRange.location;
+  if (IsIMEComposing()) {
+    // The composition may be at different offset from the selection start
+    // offset at dispatching compositionstart because start of composition
+    // is fixed when composition string becomes non-empty in the editor.
+    // Therefore, we need to use query event which is relative to insertion
+    // point.
+    options.mRelativeToInsertionPoint = true;
+    startOffset -= mIMECompositionStart;
+  }
+  textContent.InitForQueryTextContent(startOffset, aRange.length, options);
+  textContent.RequestFontRanges();
+  DispatchEvent(textContent);
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::GetAttributedSubstringFromRange, "
+     "textContent={ mSucceeded=%s, mReply={ mString=\"%s\", mOffset=%u } }",
+     this, TrueOrFalse(textContent.mSucceeded),
+     NS_ConvertUTF16toUTF8(textContent.mReply.mString).get(),
+     textContent.mReply.mOffset));
+
+  if (!textContent.mSucceeded) {
+    return nil;
+  }
+
+  // We don't set vertical information at this point.  If required,
+  // OS will calls drawsVerticallyForCharacterAtIndex.
+  NSMutableAttributedString* result =
+    nsCocoaUtils::GetNSMutableAttributedString(textContent.mReply.mString,
+                                               textContent.mReply.mFontRanges,
+                                               false,
+                                               mWidget->BackingScaleFactor());
+  if (aActualRange) {
+    aActualRange->location = textContent.mReply.mOffset;
+    aActualRange->length = textContent.mReply.mString.Length();
+  }
+  return result;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+bool
+IMEInputHandler::HasMarkedText()
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::HasMarkedText, "
+     "mMarkedRange={ location=%llu, length=%llu }",
+     this, mMarkedRange.location, mMarkedRange.length));
+
+  return (mMarkedRange.location != NSNotFound) && (mMarkedRange.length != 0);
+}
+
+NSRange
+IMEInputHandler::MarkedRange()
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::MarkedRange, "
+     "mMarkedRange={ location=%llu, length=%llu }",
+     this, mMarkedRange.location, mMarkedRange.length));
+
+  if (!HasMarkedText()) {
+    return NSMakeRange(NSNotFound, 0);
+  }
+  return mMarkedRange;
+}
+
+NSRange
+IMEInputHandler::SelectedRange()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::SelectedRange, Destroyed()=%s, mSelectedRange={ "
+     "location=%llu, length=%llu }",
+     this, TrueOrFalse(Destroyed()), mSelectedRange.location,
+     mSelectedRange.length));
+
+  if (Destroyed()) {
+    return mSelectedRange;
+  }
+
+  if (mSelectedRange.location != NSNotFound) {
+    MOZ_ASSERT(mIMEHasFocus);
+    return mSelectedRange;
+  }
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  WidgetQueryContentEvent selection(true, eQuerySelectedText, mWidget);
+  DispatchEvent(selection);
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::SelectedRange, selection={ mSucceeded=%s, "
+     "mReply={ mOffset=%u, mString.Length()=%u } }",
+     this, TrueOrFalse(selection.mSucceeded), selection.mReply.mOffset,
+     selection.mReply.mString.Length()));
+
+  if (!selection.mSucceeded) {
+    return mSelectedRange;
+  }
+
+  mWritingMode = selection.GetWritingMode();
+  mRangeForWritingMode = NSMakeRange(selection.mReply.mOffset,
+                                     selection.mReply.mString.Length());
+
+  if (mIMEHasFocus) {
+    mSelectedRange = mRangeForWritingMode;
+  }
+
+  return mRangeForWritingMode;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(mSelectedRange);
+}
+
+bool
+IMEInputHandler::DrawsVerticallyForCharacterAtIndex(uint32_t aCharIndex)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (Destroyed()) {
+    return false;
+  }
+
+  if (mRangeForWritingMode.location == NSNotFound) {
+    // Update cached writing-mode value for the current selection.
+    SelectedRange();
+  }
+
+  if (aCharIndex < mRangeForWritingMode.location ||
+      aCharIndex > mRangeForWritingMode.location + mRangeForWritingMode.length) {
+    // It's not clear to me whether this ever happens in practice, but if an
+    // IME ever wants to query writing mode at an offset outside the current
+    // selection, the writing-mode value may not be correct for the index.
+    // In that case, use FirstRectForCharacterRange to get a fresh value.
+    // This does more work than strictly necessary (we don't need the rect here),
+    // but should be a rare case.
+    NS_WARNING("DrawsVerticallyForCharacterAtIndex not using cached writing mode");
+    NSRange range = NSMakeRange(aCharIndex, 1);
+    NSRange actualRange;
+    FirstRectForCharacterRange(range, &actualRange);
+  }
+
+  return mWritingMode.IsVertical();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+NSRect
+IMEInputHandler::FirstRectForCharacterRange(NSRange& aRange,
+                                            NSRange* aActualRange)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::FirstRectForCharacterRange, Destroyed()=%s, "
+     "aRange={ location=%llu, length=%llu }, aActualRange=%p }",
+     this, TrueOrFalse(Destroyed()), aRange.location, aRange.length,
+     aActualRange));
+
+  // XXX this returns first character rect or caret rect, it is limitation of
+  // now. We need more work for returns first line rect. But current
+  // implementation is enough for IMEs.
+
+  NSRect rect = NSMakeRect(0.0, 0.0, 0.0, 0.0);
+  NSRange actualRange = NSMakeRange(NSNotFound, 0);
+  if (aActualRange) {
+    *aActualRange = actualRange;
+  }
+  if (Destroyed() || aRange.location == NSNotFound) {
+    return rect;
+  }
+
+  RefPtr<IMEInputHandler> kungFuDeathGrip(this);
+
+  LayoutDeviceIntRect r;
+  bool useCaretRect = (aRange.length == 0);
+  if (!useCaretRect) {
+    WidgetQueryContentEvent charRect(true, eQueryTextRect, mWidget);
+    WidgetQueryContentEvent::Options options;
+    int64_t startOffset = aRange.location;
+    if (IsIMEComposing()) {
+      // The composition may be at different offset from the selection start
+      // offset at dispatching compositionstart because start of composition
+      // is fixed when composition string becomes non-empty in the editor.
+      // Therefore, we need to use query event which is relative to insertion
+      // point.
+      options.mRelativeToInsertionPoint = true;
+      startOffset -= mIMECompositionStart;
+    }
+    charRect.InitForQueryTextRect(startOffset, 1, options);
+    DispatchEvent(charRect);
+    if (charRect.mSucceeded) {
+      r = charRect.mReply.mRect;
+      actualRange.location = charRect.mReply.mOffset;
+      actualRange.length = charRect.mReply.mString.Length();
+      mWritingMode = charRect.GetWritingMode();
+      mRangeForWritingMode = actualRange;
+    } else {
+      useCaretRect = true;
+    }
+  }
+
+  if (useCaretRect) {
+    WidgetQueryContentEvent caretRect(true, eQueryCaretRect, mWidget);
+    WidgetQueryContentEvent::Options options;
+    int64_t startOffset = aRange.location;
+    if (IsIMEComposing()) {
+      // The composition may be at different offset from the selection start
+      // offset at dispatching compositionstart because start of composition
+      // is fixed when composition string becomes non-empty in the editor.
+      // Therefore, we need to use query event which is relative to insertion
+      // point.
+      options.mRelativeToInsertionPoint = true;
+      startOffset -= mIMECompositionStart;
+    }
+    caretRect.InitForQueryCaretRect(startOffset, options);
+    DispatchEvent(caretRect);
+    if (!caretRect.mSucceeded) {
+      return rect;
+    }
+    r = caretRect.mReply.mRect;
+    r.width = 0;
+    actualRange.location = caretRect.mReply.mOffset;
+    actualRange.length = 0;
+  }
+
+  nsIWidget* rootWidget = mWidget->GetTopLevelWidget();
+  NSWindow* rootWindow =
+    static_cast<NSWindow*>(rootWidget->GetNativeData(NS_NATIVE_WINDOW));
+  NSView* rootView =
+    static_cast<NSView*>(rootWidget->GetNativeData(NS_NATIVE_WIDGET));
+  if (!rootWindow || !rootView) {
+    return rect;
+  }
+  rect = nsCocoaUtils::DevPixelsToCocoaPoints(r, mWidget->BackingScaleFactor());
+  rect = [rootView convertRect:rect toView:nil];
+  rect.origin = nsCocoaUtils::ConvertPointToScreen(rootWindow, rect.origin);
+
+  if (aActualRange) {
+    *aActualRange = actualRange;
+  }
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::FirstRectForCharacterRange, "
+     "useCaretRect=%s rect={ x=%f, y=%f, width=%f, height=%f }, "
+     "actualRange={ location=%llu, length=%llu }",
+     this, TrueOrFalse(useCaretRect), rect.origin.x, rect.origin.y,
+     rect.size.width, rect.size.height, actualRange.location,
+     actualRange.length));
+
+  return rect;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSMakeRect(0.0, 0.0, 0.0, 0.0));
+}
+
+NSUInteger
+IMEInputHandler::CharacterIndexForPoint(NSPoint& aPoint)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::CharacterIndexForPoint, aPoint={ x=%f, y=%f }",
+     this, aPoint.x, aPoint.y));
+
+  NSWindow* mainWindow = [NSApp mainWindow];
+  if (!mWidget || !mainWindow) {
+    return NSNotFound;
+  }
+
+  WidgetQueryContentEvent charAt(true, eQueryCharacterAtPoint, mWidget);
+  NSPoint ptInWindow = nsCocoaUtils::ConvertPointFromScreen(mainWindow, aPoint);
+  NSPoint ptInView = [mView convertPoint:ptInWindow fromView:nil];
+  charAt.mRefPoint.x =
+    static_cast<int32_t>(ptInView.x) * mWidget->BackingScaleFactor();
+  charAt.mRefPoint.y =
+    static_cast<int32_t>(ptInView.y) * mWidget->BackingScaleFactor();
+  mWidget->DispatchWindowEvent(charAt);
+  if (!charAt.mSucceeded ||
+      charAt.mReply.mOffset == WidgetQueryContentEvent::NOT_FOUND ||
+      charAt.mReply.mOffset >= static_cast<uint32_t>(NSNotFound)) {
+    return NSNotFound;
+  }
+
+  return charAt.mReply.mOffset;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSNotFound);
+}
+
+extern "C" {
+extern NSString *NSTextInputReplacementRangeAttributeName;
+}
+
+NSArray*
+IMEInputHandler::GetValidAttributesForMarkedText()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::GetValidAttributesForMarkedText", this));
+
+  // Return same attributes as Chromium (see render_widget_host_view_mac.mm)
+  // because most IMEs must be tested with Safari (OS default) and Chrome
+  // (having most market share).  Therefore, we need to follow their behavior.
+  // XXX It might be better to reuse an array instance for this result because
+  //     this may be called a lot.  Note that Chromium does so.
+  return [NSArray arrayWithObjects:NSUnderlineStyleAttributeName,
+                                   NSUnderlineColorAttributeName,
+                                   NSMarkedClauseSegmentAttributeName,
+                                   NSTextInputReplacementRangeAttributeName,
+                                   nil];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  IMEInputHandler implementation #2
+ *
+ ******************************************************************************/
+
+IMEInputHandler::IMEInputHandler(nsChildView* aWidget,
+                                 NSView<mozView> *aNativeView)
+  : TextInputHandlerBase(aWidget, aNativeView)
+  , mPendingMethods(0)
+  , mIMECompositionString(nullptr)
+  , mIMECompositionStart(UINT32_MAX)
+  , mIsIMEComposing(false)
+  , mIsIMEEnabled(true)
+  , mIsASCIICapableOnly(false)
+  , mIgnoreIMECommit(false)
+  , mIsInFocusProcessing(false)
+  , mIMEHasFocus(false)
+{
+  InitStaticMembers();
+
+  mMarkedRange.location = NSNotFound;
+  mMarkedRange.length = 0;
+  mSelectedRange.location = NSNotFound;
+  mSelectedRange.length = 0;
+}
+
+IMEInputHandler::~IMEInputHandler()
+{
+  if (mTimer) {
+    mTimer->Cancel();
+    mTimer = nullptr;
+  }
+  if (sFocusedIMEHandler == this) {
+    sFocusedIMEHandler = nullptr;
+  }
+  if (mIMECompositionString) {
+    [mIMECompositionString release];
+    mIMECompositionString = nullptr;
+  }
+}
+
+void
+IMEInputHandler::OnFocusChangeInGecko(bool aFocus)
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::OnFocusChangeInGecko, aFocus=%s, Destroyed()=%s, "
+     "sFocusedIMEHandler=%p",
+     this, TrueOrFalse(aFocus), TrueOrFalse(Destroyed()), sFocusedIMEHandler));
+
+  mSelectedRange.location = NSNotFound; // Marking dirty
+  mIMEHasFocus = aFocus;
+
+  // This is called when the native focus is changed and when the native focus
+  // isn't changed but the focus is changed in Gecko.
+  if (!aFocus) {
+    if (sFocusedIMEHandler == this)
+      sFocusedIMEHandler = nullptr;
+    return;
+  }
+
+  sFocusedIMEHandler = this;
+  mIsInFocusProcessing = true;
+
+  // We need to notify IME of focus change in Gecko as native focus change
+  // because the window level of the focused element in Gecko may be changed.
+  mPendingMethods |= kNotifyIMEOfFocusChangeInGecko;
+  ResetTimer();
+}
+
+bool
+IMEInputHandler::OnDestroyWidget(nsChildView* aDestroyingWidget)
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::OnDestroyWidget, aDestroyingWidget=%p, "
+     "sFocusedIMEHandler=%p, IsIMEComposing()=%s",
+     this, aDestroyingWidget, sFocusedIMEHandler,
+     TrueOrFalse(IsIMEComposing())));
+
+  // If we're not focused, the focused IMEInputHandler may have been
+  // created by another widget/nsChildView.
+  if (sFocusedIMEHandler && sFocusedIMEHandler != this) {
+    sFocusedIMEHandler->OnDestroyWidget(aDestroyingWidget);
+  }
+
+  if (!TextInputHandlerBase::OnDestroyWidget(aDestroyingWidget)) {
+    return false;
+  }
+
+  if (IsIMEComposing()) {
+    // If our view is in the composition, we should clean up it.
+    CancelIMEComposition();
+  }
+
+  mSelectedRange.location = NSNotFound; // Marking dirty
+  mIMEHasFocus = false;
+
+  return true;
+}
+
+void
+IMEInputHandler::SendCommittedText(NSString *aString)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::SendCommittedText, mView=%p, mWidget=%p, "
+     "inputContext=%p, mIsIMEComposing=%s",
+     this, mView, mWidget, mView ? [mView inputContext] : nullptr,
+     TrueOrFalse(mIsIMEComposing), mWidget));
+
+  NS_ENSURE_TRUE(mWidget, );
+  // XXX We should send the string without mView.
+  if (!mView) {
+    return;
+  }
+
+  NSAttributedString* attrStr =
+    [[NSAttributedString alloc] initWithString:aString];
+  if ([mView conformsToProtocol:@protocol(NSTextInputClient)]) {
+    NSObject<NSTextInputClient>* textInputClient =
+      static_cast<NSObject<NSTextInputClient>*>(mView);
+    [textInputClient insertText:attrStr
+               replacementRange:NSMakeRange(NSNotFound, 0)];
+  }
+
+  // Last resort.  If we cannot retrieve NSTextInputProtocol from mView
+  // or blocking to call our InsertText(), we should call InsertText()
+  // directly to commit composition forcibly.
+  if (mIsIMEComposing) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::SendCommittedText, trying to insert text directly "
+       "due to IME not calling our InsertText()", this));
+    static_cast<TextInputHandler*>(this)->InsertText(attrStr);
+    MOZ_ASSERT(!mIsIMEComposing);
+  }
+
+  [attrStr release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+IMEInputHandler::KillIMEComposition()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::KillIMEComposition, mView=%p, mWidget=%p, "
+     "inputContext=%p, mIsIMEComposing=%s, "
+     "Destroyed()=%s, IsFocused()=%s",
+     this, mView, mWidget, mView ? [mView inputContext] : nullptr,
+     TrueOrFalse(mIsIMEComposing), TrueOrFalse(Destroyed()),
+     TrueOrFalse(IsFocused())));
+
+  if (Destroyed()) {
+    return;
+  }
+
+  if (IsFocused()) {
+    NS_ENSURE_TRUE_VOID(mView);
+    NSTextInputContext* inputContext = [mView inputContext];
+    NS_ENSURE_TRUE_VOID(inputContext);
+    [inputContext discardMarkedText];
+    return;
+  }
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::KillIMEComposition, Pending...", this));
+
+  // Commit the composition internally.
+  SendCommittedText(mIMECompositionString);
+  NS_ASSERTION(!mIsIMEComposing, "We're still in a composition");
+  // The pending method will be fired by the next focus event.
+  mPendingMethods |= kDiscardIMEComposition;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+IMEInputHandler::CommitIMEComposition()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!IsIMEComposing())
+    return;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::CommitIMEComposition, mIMECompositionString=%s",
+     this, GetCharacters(mIMECompositionString)));
+
+  KillIMEComposition();
+
+  if (!IsIMEComposing())
+    return;
+
+  // If the composition is still there, KillIMEComposition only kills the
+  // composition in TSM.  We also need to finish the our composition too.
+  SendCommittedText(mIMECompositionString);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+IMEInputHandler::CancelIMEComposition()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!IsIMEComposing())
+    return;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::CancelIMEComposition, mIMECompositionString=%s",
+     this, GetCharacters(mIMECompositionString)));
+
+  // For canceling the current composing, we need to ignore the param of
+  // insertText.  But this code is ugly...
+  mIgnoreIMECommit = true;
+  KillIMEComposition();
+  mIgnoreIMECommit = false;
+
+  if (!IsIMEComposing())
+    return;
+
+  // If the composition is still there, KillIMEComposition only kills the
+  // composition in TSM.  We also need to kill the our composition too.
+  SendCommittedText(@"");
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+bool
+IMEInputHandler::IsFocused()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_ENSURE_TRUE(!Destroyed(), false);
+  NSWindow* window = [mView window];
+  NS_ENSURE_TRUE(window, false);
+  return [window firstResponder] == mView &&
+         [window isKeyWindow] &&
+         [[NSApplication sharedApplication] isActive];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+bool
+IMEInputHandler::IsIMEOpened()
+{
+  TISInputSourceWrapper tis;
+  tis.InitByCurrentInputSource();
+  return tis.IsOpenedIMEMode();
+}
+
+void
+IMEInputHandler::SetASCIICapableOnly(bool aASCIICapableOnly)
+{
+  if (aASCIICapableOnly == mIsASCIICapableOnly)
+    return;
+
+  CommitIMEComposition();
+  mIsASCIICapableOnly = aASCIICapableOnly;
+  SyncASCIICapableOnly();
+}
+
+void
+IMEInputHandler::EnableIME(bool aEnableIME)
+{
+  if (aEnableIME == mIsIMEEnabled)
+    return;
+
+  CommitIMEComposition();
+  mIsIMEEnabled = aEnableIME;
+}
+
+void
+IMEInputHandler::SetIMEOpenState(bool aOpenIME)
+{
+  if (!IsFocused() || IsIMEOpened() == aOpenIME)
+    return;
+
+  if (!aOpenIME) {
+    TISInputSourceWrapper tis;
+    tis.InitByCurrentASCIICapableInputSource();
+    tis.Select();
+    return;
+  }
+
+  // If we know the latest IME opened mode, we should select it.
+  if (sLatestIMEOpenedModeInputSourceID) {
+    TISInputSourceWrapper tis;
+    tis.InitByInputSourceID(sLatestIMEOpenedModeInputSourceID);
+    tis.Select();
+    return;
+  }
+
+  // XXX If the current input source is a mode of IME, we should turn on it,
+  // but we haven't found such way...
+
+  // Finally, we should refer the system locale but this is a little expensive,
+  // we shouldn't retry this (if it was succeeded, we already set
+  // sLatestIMEOpenedModeInputSourceID at that time).
+  static bool sIsPrefferredIMESearched = false;
+  if (sIsPrefferredIMESearched)
+    return;
+  sIsPrefferredIMESearched = true;
+  OpenSystemPreferredLanguageIME();
+}
+
+void
+IMEInputHandler::OpenSystemPreferredLanguageIME()
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::OpenSystemPreferredLanguageIME", this));
+
+  CFArrayRef langList = ::CFLocaleCopyPreferredLanguages();
+  if (!langList) {
+    MOZ_LOG(gLog, LogLevel::Info,
+      ("%p IMEInputHandler::OpenSystemPreferredLanguageIME, langList is NULL",
+       this));
+    return;
+  }
+  CFIndex count = ::CFArrayGetCount(langList);
+  for (CFIndex i = 0; i < count; i++) {
+    CFLocaleRef locale =
+      ::CFLocaleCreate(kCFAllocatorDefault,
+          static_cast<CFStringRef>(::CFArrayGetValueAtIndex(langList, i)));
+    if (!locale) {
+      continue;
+    }
+
+    bool changed = false;
+    CFStringRef lang = static_cast<CFStringRef>(
+      ::CFLocaleGetValue(locale, kCFLocaleLanguageCode));
+    NS_ASSERTION(lang, "lang is null");
+    if (lang) {
+      TISInputSourceWrapper tis;
+      tis.InitByLanguage(lang);
+      if (tis.IsOpenedIMEMode()) {
+        if (MOZ_LOG_TEST(gLog, LogLevel::Info)) {
+          CFStringRef foundTIS;
+          tis.GetInputSourceID(foundTIS);
+          MOZ_LOG(gLog, LogLevel::Info,
+            ("%p IMEInputHandler::OpenSystemPreferredLanguageIME, "
+             "foundTIS=%s, lang=%s",
+             this, GetCharacters(foundTIS), GetCharacters(lang)));
+        }
+        tis.Select();
+        changed = true;
+      }
+    }
+    ::CFRelease(locale);
+    if (changed) {
+      break;
+    }
+  }
+  ::CFRelease(langList);
+}
+
+void
+IMEInputHandler::OnSelectionChange(const IMENotification& aIMENotification)
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p IMEInputHandler::OnSelectionChange", this));
+
+  if (aIMENotification.mSelectionChangeData.mOffset == UINT32_MAX) {
+    mSelectedRange.location = NSNotFound;
+    mSelectedRange.length = 0;
+    mRangeForWritingMode.location = NSNotFound;
+    mRangeForWritingMode.length = 0;
+    return;
+  }
+
+  mWritingMode = aIMENotification.mSelectionChangeData.GetWritingMode();
+  mRangeForWritingMode =
+    NSMakeRange(aIMENotification.mSelectionChangeData.mOffset,
+                aIMENotification.mSelectionChangeData.Length());
+  if (mIMEHasFocus) {
+    mSelectedRange = mRangeForWritingMode;
+  }
+}
+
+bool
+IMEInputHandler::OnHandleEvent(NSEvent* aEvent)
+{
+  if (!IsFocused()) {
+    return false;
+  }
+  NSTextInputContext* inputContext = [mView inputContext];
+  return [inputContext handleEvent:aEvent];
+}
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  TextInputHandlerBase implementation
+ *
+ ******************************************************************************/
+
+int32_t TextInputHandlerBase::sSecureEventInputCount = 0;
+
+NS_IMPL_ISUPPORTS(TextInputHandlerBase,
+                  TextEventDispatcherListener,
+                  nsISupportsWeakReference)
+
+TextInputHandlerBase::TextInputHandlerBase(nsChildView* aWidget,
+                                           NSView<mozView> *aNativeView)
+  : mWidget(aWidget)
+  , mDispatcher(aWidget->GetTextEventDispatcher())
+{
+  gHandlerInstanceCount++;
+  mView = [aNativeView retain];
+}
+
+TextInputHandlerBase::~TextInputHandlerBase()
+{
+  [mView release];
+  if (--gHandlerInstanceCount == 0) {
+    TISInputSourceWrapper::Shutdown();
+  }
+}
+
+bool
+TextInputHandlerBase::OnDestroyWidget(nsChildView* aDestroyingWidget)
+{
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandlerBase::OnDestroyWidget, "
+     "aDestroyingWidget=%p, mWidget=%p",
+     this, aDestroyingWidget, mWidget));
+
+  if (aDestroyingWidget != mWidget) {
+    return false;
+  }
+
+  mWidget = nullptr;
+  mDispatcher = nullptr;
+  return true;
+}
+
+bool
+TextInputHandlerBase::DispatchEvent(WidgetGUIEvent& aEvent)
+{
+  return mWidget->DispatchWindowEvent(aEvent);
+}
+
+void
+TextInputHandlerBase::InitKeyEvent(NSEvent *aNativeKeyEvent,
+                                   WidgetKeyboardEvent& aKeyEvent,
+                                   const nsAString* aInsertString)
+{
+  NS_ASSERTION(aNativeKeyEvent, "aNativeKeyEvent must not be NULL");
+
+  if (mKeyboardOverride.mOverrideEnabled) {
+    TISInputSourceWrapper tis;
+    tis.InitByLayoutID(mKeyboardOverride.mKeyboardLayout, true);
+    tis.InitKeyEvent(aNativeKeyEvent, aKeyEvent, aInsertString);
+    return;
+  }
+  TISInputSourceWrapper::CurrentInputSource().
+    InitKeyEvent(aNativeKeyEvent, aKeyEvent, aInsertString);
+}
+
+nsresult
+TextInputHandlerBase::SynthesizeNativeKeyEvent(
+                        int32_t aNativeKeyboardLayout,
+                        int32_t aNativeKeyCode,
+                        uint32_t aModifierFlags,
+                        const nsAString& aCharacters,
+                        const nsAString& aUnmodifiedCharacters)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  static const uint32_t sModifierFlagMap[][2] = {
+    { nsIWidget::CAPS_LOCK,       NSAlphaShiftKeyMask },
+    { nsIWidget::SHIFT_L,         NSShiftKeyMask      | 0x0002 },
+    { nsIWidget::SHIFT_R,         NSShiftKeyMask      | 0x0004 },
+    { nsIWidget::CTRL_L,          NSControlKeyMask    | 0x0001 },
+    { nsIWidget::CTRL_R,          NSControlKeyMask    | 0x2000 },
+    { nsIWidget::ALT_L,           NSAlternateKeyMask  | 0x0020 },
+    { nsIWidget::ALT_R,           NSAlternateKeyMask  | 0x0040 },
+    { nsIWidget::COMMAND_L,       NSCommandKeyMask    | 0x0008 },
+    { nsIWidget::COMMAND_R,       NSCommandKeyMask    | 0x0010 },
+    { nsIWidget::NUMERIC_KEY_PAD, NSNumericPadKeyMask },
+    { nsIWidget::HELP,            NSHelpKeyMask },
+    { nsIWidget::FUNCTION,        NSFunctionKeyMask }
+  };
+
+  uint32_t modifierFlags = 0;
+  for (uint32_t i = 0; i < ArrayLength(sModifierFlagMap); ++i) {
+    if (aModifierFlags & sModifierFlagMap[i][0]) {
+      modifierFlags |= sModifierFlagMap[i][1];
+    }
+  }
+
+  NSInteger windowNumber = [[mView window] windowNumber];
+  bool sendFlagsChangedEvent = IsModifierKey(aNativeKeyCode);
+  NSEventType eventType = sendFlagsChangedEvent ? NSFlagsChanged : NSKeyDown;
+  NSEvent* downEvent =
+    [NSEvent     keyEventWithType:eventType
+                         location:NSMakePoint(0,0)
+                    modifierFlags:modifierFlags
+                        timestamp:0
+                     windowNumber:windowNumber
+                          context:[NSGraphicsContext currentContext]
+                       characters:nsCocoaUtils::ToNSString(aCharacters)
+      charactersIgnoringModifiers:nsCocoaUtils::ToNSString(aUnmodifiedCharacters)
+                        isARepeat:NO
+                          keyCode:aNativeKeyCode];
+
+  NSEvent* upEvent = sendFlagsChangedEvent ?
+    nil : nsCocoaUtils::MakeNewCocoaEventWithType(NSKeyUp, downEvent);
+
+  if (downEvent && (sendFlagsChangedEvent || upEvent)) {
+    KeyboardLayoutOverride currentLayout = mKeyboardOverride;
+    mKeyboardOverride.mKeyboardLayout = aNativeKeyboardLayout;
+    mKeyboardOverride.mOverrideEnabled = true;
+    [NSApp sendEvent:downEvent];
+    if (upEvent) {
+      [NSApp sendEvent:upEvent];
+    }
+    // processKeyDownEvent and keyUp block exceptions so we're sure to
+    // reach here to restore mKeyboardOverride
+    mKeyboardOverride = currentLayout;
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NSInteger
+TextInputHandlerBase::GetWindowLevel()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandlerBase::GetWindowLevel, Destryoed()=%s",
+     this, TrueOrFalse(Destroyed())));
+
+  if (Destroyed()) {
+    return NSNormalWindowLevel;
+  }
+
+  // When an <input> element on a XUL <panel> is focused, the actual focused view
+  // is the panel's parent view (mView). But the editor is displayed on the
+  // popped-up widget's view (editorView).  We want the latter's window level.
+  NSView<mozView>* editorView = mWidget->GetEditorView();
+  NS_ENSURE_TRUE(editorView, NSNormalWindowLevel);
+  NSInteger windowLevel = [[editorView window] level];
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandlerBase::GetWindowLevel, windowLevel=%s (%X)",
+     this, GetWindowLevelName(windowLevel), windowLevel));
+
+  return windowLevel;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSNormalWindowLevel);
+}
+
+NS_IMETHODIMP
+TextInputHandlerBase::AttachNativeKeyEvent(WidgetKeyboardEvent& aKeyEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // Don't try to replace a native event if one already exists.
+  // OS X doesn't have an OS modifier, can't make a native event.
+  if (aKeyEvent.mNativeKeyEvent || aKeyEvent.mModifiers & MODIFIER_OS) {
+    return NS_OK;
+  }
+
+  MOZ_LOG(gLog, LogLevel::Info,
+    ("%p TextInputHandlerBase::AttachNativeKeyEvent, key=0x%X, char=0x%X, "
+     "mod=0x%X", this, aKeyEvent.mKeyCode, aKeyEvent.mCharCode,
+     aKeyEvent.mModifiers));
+
+  NSEventType eventType;
+  if (aKeyEvent.mMessage == eKeyUp) {
+    eventType = NSKeyUp;
+  } else {
+    eventType = NSKeyDown;
+  }
+
+  static const uint32_t sModifierFlagMap[][2] = {
+    { MODIFIER_SHIFT,    NSShiftKeyMask },
+    { MODIFIER_CONTROL,  NSControlKeyMask },
+    { MODIFIER_ALT,      NSAlternateKeyMask },
+    { MODIFIER_ALTGRAPH, NSAlternateKeyMask },
+    { MODIFIER_META,     NSCommandKeyMask },
+    { MODIFIER_CAPSLOCK, NSAlphaShiftKeyMask },
+    { MODIFIER_NUMLOCK,  NSNumericPadKeyMask }
+  };
+
+  NSUInteger modifierFlags = 0;
+  for (uint32_t i = 0; i < ArrayLength(sModifierFlagMap); ++i) {
+    if (aKeyEvent.mModifiers & sModifierFlagMap[i][0]) {
+      modifierFlags |= sModifierFlagMap[i][1];
+    }
+  }
+
+  NSInteger windowNumber = [[mView window] windowNumber];
+
+  NSString* characters;
+  if (aKeyEvent.mCharCode) {
+    characters = [NSString stringWithCharacters:
+      reinterpret_cast<const unichar*>(&(aKeyEvent.mCharCode)) length:1];
+  } else {
+    uint32_t cocoaCharCode =
+      nsCocoaUtils::ConvertGeckoKeyCodeToMacCharCode(aKeyEvent.mKeyCode);
+    characters = [NSString stringWithCharacters:
+      reinterpret_cast<const unichar*>(&cocoaCharCode) length:1];
+  }
+
+  aKeyEvent.mNativeKeyEvent =
+    [NSEvent     keyEventWithType:eventType
+                         location:NSMakePoint(0,0)
+                    modifierFlags:modifierFlags
+                        timestamp:0
+                     windowNumber:windowNumber
+                          context:[NSGraphicsContext currentContext]
+                       characters:characters
+      charactersIgnoringModifiers:characters
+                        isARepeat:NO
+                          keyCode:0]; // Native key code not currently needed
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+bool
+TextInputHandlerBase::SetSelection(NSRange& aRange)
+{
+  MOZ_ASSERT(!Destroyed());
+
+  RefPtr<TextInputHandlerBase> kungFuDeathGrip(this);
+  WidgetSelectionEvent selectionEvent(true, eSetSelection, mWidget);
+  selectionEvent.mOffset = aRange.location;
+  selectionEvent.mLength = aRange.length;
+  selectionEvent.mReversed = false;
+  selectionEvent.mExpandToClusterBoundary = false;
+  DispatchEvent(selectionEvent);
+  NS_ENSURE_TRUE(selectionEvent.mSucceeded, false);
+  return !Destroyed();
+}
+
+/* static */ bool
+TextInputHandlerBase::IsPrintableChar(char16_t aChar)
+{
+  return (aChar >= 0x20 && aChar <= 0x7E) || aChar >= 0xA0;
+}
+
+
+/* static */ bool
+TextInputHandlerBase::IsSpecialGeckoKey(UInt32 aNativeKeyCode)
+{
+  // this table is used to determine which keys are special and should not
+  // generate a charCode
+  switch (aNativeKeyCode) {
+    // modifiers - we don't get separate events for these yet
+    case kVK_Escape:
+    case kVK_Shift:
+    case kVK_RightShift:
+    case kVK_Command:
+    case kVK_RightCommand:
+    case kVK_CapsLock:
+    case kVK_Control:
+    case kVK_RightControl:
+    case kVK_Option:
+    case kVK_RightOption:
+    case kVK_ANSI_KeypadClear:
+    case kVK_Function:
+
+    // function keys
+    case kVK_F1:
+    case kVK_F2:
+    case kVK_F3:
+    case kVK_F4:
+    case kVK_F5:
+    case kVK_F6:
+    case kVK_F7:
+    case kVK_F8:
+    case kVK_F9:
+    case kVK_F10:
+    case kVK_F11:
+    case kVK_F12:
+    case kVK_PC_Pause:
+    case kVK_PC_ScrollLock:
+    case kVK_PC_PrintScreen:
+    case kVK_F16:
+    case kVK_F17:
+    case kVK_F18:
+    case kVK_F19:
+
+    case kVK_PC_Insert:
+    case kVK_PC_Delete:
+    case kVK_Tab:
+    case kVK_PC_Backspace:
+    case kVK_PC_ContextMenu:
+
+    case kVK_JIS_Eisu:
+    case kVK_JIS_Kana:
+
+    case kVK_Home:
+    case kVK_End:
+    case kVK_PageUp:
+    case kVK_PageDown:
+    case kVK_LeftArrow:
+    case kVK_RightArrow:
+    case kVK_UpArrow:
+    case kVK_DownArrow:
+    case kVK_Return:
+    case kVK_ANSI_KeypadEnter:
+    case kVK_Powerbook_KeypadEnter:
+      return true;
+  }
+  return false;
+}
+
+/* static */ bool
+TextInputHandlerBase::IsNormalCharInputtingEvent(
+                        const WidgetKeyboardEvent& aKeyEvent)
+{
+  // this is not character inputting event, simply.
+  if (aKeyEvent.mNativeCharacters.IsEmpty() ||
+      aKeyEvent.IsMeta()) {
+    return false;
+  }
+  return !IsControlChar(aKeyEvent.mNativeCharacters[0]);
+}
+
+/* static */ bool
+TextInputHandlerBase::IsModifierKey(UInt32 aNativeKeyCode)
+{
+  switch (aNativeKeyCode) {
+    case kVK_CapsLock:
+    case kVK_RightCommand:
+    case kVK_Command:
+    case kVK_Shift:
+    case kVK_Option:
+    case kVK_Control:
+    case kVK_RightShift:
+    case kVK_RightOption:
+    case kVK_RightControl:
+    case kVK_Function:
+      return true;
+  }
+  return false;
+}
+
+/* static */ void
+TextInputHandlerBase::EnableSecureEventInput()
+{
+  sSecureEventInputCount++;
+  ::EnableSecureEventInput();
+}
+
+/* static */ void
+TextInputHandlerBase::DisableSecureEventInput()
+{
+  if (!sSecureEventInputCount) {
+    return;
+  }
+  sSecureEventInputCount--;
+  ::DisableSecureEventInput();
+}
+
+/* static */ bool
+TextInputHandlerBase::IsSecureEventInputEnabled()
+{
+  NS_ASSERTION(!!sSecureEventInputCount == !!::IsSecureEventInputEnabled(),
+               "Some other process has enabled secure event input");
+  return !!sSecureEventInputCount;
+}
+
+/* static */ void
+TextInputHandlerBase::EnsureSecureEventInputDisabled()
+{
+  while (sSecureEventInputCount) {
+    TextInputHandlerBase::DisableSecureEventInput();
+  }
+}
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  TextInputHandlerBase::KeyEventState implementation
+ *
+ ******************************************************************************/
+
+void
+TextInputHandlerBase::KeyEventState::InitKeyEvent(
+                                       TextInputHandlerBase* aHandler,
+                                       WidgetKeyboardEvent& aKeyEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_ASSERT(aHandler);
+  MOZ_RELEASE_ASSERT(mKeyEvent);
+
+  NSEvent* nativeEvent = mKeyEvent;
+  if (!mInsertedString.IsEmpty()) {
+    nsAutoString unhandledString;
+    GetUnhandledString(unhandledString);
+    NSString* unhandledNSString =
+      nsCocoaUtils::ToNSString(unhandledString);
+    // If the key event's some characters were already handled by
+    // InsertString() calls, we need to create a dummy event which doesn't
+    // include the handled characters.
+    nativeEvent =
+      [NSEvent keyEventWithType:[mKeyEvent type]
+                       location:[mKeyEvent locationInWindow]
+                  modifierFlags:[mKeyEvent modifierFlags]
+                      timestamp:[mKeyEvent timestamp]
+                   windowNumber:[mKeyEvent windowNumber]
+                        context:[mKeyEvent context]
+                     characters:unhandledNSString
+    charactersIgnoringModifiers:[mKeyEvent charactersIgnoringModifiers]
+                      isARepeat:[mKeyEvent isARepeat]
+                        keyCode:[mKeyEvent keyCode]];
+  }
+
+  aHandler->InitKeyEvent(nativeEvent, aKeyEvent, mInsertString);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+TextInputHandlerBase::KeyEventState::GetUnhandledString(
+                                       nsAString& aUnhandledString) const
+{
+  aUnhandledString.Truncate();
+  if (NS_WARN_IF(!mKeyEvent)) {
+    return;
+  }
+  nsAutoString characters;
+  nsCocoaUtils::GetStringForNSString([mKeyEvent characters],
+                                     characters);
+  if (characters.IsEmpty()) {
+    return;
+  }
+  if (mInsertedString.IsEmpty()) {
+    aUnhandledString = characters;
+    return;
+  }
+
+  // The insertes string must match with the start of characters.
+  MOZ_ASSERT(StringBeginsWith(characters, mInsertedString));
+
+  aUnhandledString = nsDependentSubstring(characters, mInsertedString.Length());
+}
+
+#pragma mark -
+
+
+/******************************************************************************
+ *
+ *  TextInputHandlerBase::AutoInsertStringClearer implementation
+ *
+ ******************************************************************************/
+
+TextInputHandlerBase::AutoInsertStringClearer::~AutoInsertStringClearer()
+{
+  if (mState && mState->mInsertString) {
+    // If inserting string is a part of characters of the event,
+    // we should record it as inserted string.
+    nsAutoString characters;
+    nsCocoaUtils::GetStringForNSString([mState->mKeyEvent characters],
+                                       characters);
+    nsAutoString insertedString(mState->mInsertedString);
+    insertedString += *mState->mInsertString;
+    if (StringBeginsWith(characters, insertedString)) {
+      mState->mInsertedString = insertedString;
+    }
+  }
+  if (mState) {
+    mState->mInsertString = nullptr;
+  }
+}
diff --git a/widget/cocoa/VibrancyManager.h b/widget/cocoa/VibrancyManager.h
new file mode 100644
index 0000000000..04b1ad1cda
--- /dev/null
+++ b/widget/cocoa/VibrancyManager.h
@@ -0,0 +1,120 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef VibrancyManager_h
+#define VibrancyManager_h
+
+#include "mozilla/Assertions.h"
+#include "nsClassHashtable.h"
+#include "nsRegion.h"
+#include "nsTArray.h"
+#include "ViewRegion.h"
+
+#import <Foundation/NSGeometry.h>
+
+@class NSColor;
+@class NSView;
+class nsChildView;
+
+namespace mozilla {
+
+enum class VibrancyType {
+  LIGHT,
+  DARK,
+  TOOLTIP,
+  MENU,
+  HIGHLIGHTED_MENUITEM,
+  SHEET,
+  SOURCE_LIST,
+  SOURCE_LIST_SELECTION,
+  ACTIVE_SOURCE_LIST_SELECTION
+};
+
+/**
+ * VibrancyManager takes care of updating the vibrant regions of a window.
+ * Vibrancy is a visual look that was introduced on OS X starting with 10.10.
+ * An app declares vibrant window regions to the window server, and the window
+ * server will display a blurred rendering of the screen contents from behind
+ * the window in these areas, behind the actual window contents. Consequently,
+ * the effect is only visible in areas where the window contents are not
+ * completely opaque. Usually this is achieved by clearing the background of
+ * the window prior to drawing in the vibrant areas. This is possible even if
+ * the window is declared as opaque.
+ */
+class VibrancyManager {
+public:
+  /**
+   * Create a new VibrancyManager instance and provide it with an NSView
+   * to attach NSVisualEffectViews to.
+   *
+   * @param aCoordinateConverter  The nsChildView to use for converting
+   *   nsIntRect device pixel coordinates into Cocoa NSRect coordinates. Must
+   *   outlive this VibrancyManager instance.
+   * @param aContainerView  The view that's going to be the superview of the
+   *   NSVisualEffectViews which will be created for vibrant regions.
+   */
+  VibrancyManager(const nsChildView& aCoordinateConverter,
+                  NSView* aContainerView)
+    : mCoordinateConverter(aCoordinateConverter)
+    , mContainerView(aContainerView)
+  {
+    MOZ_ASSERT(SystemSupportsVibrancy(),
+               "Don't instantiate this if !SystemSupportsVibrancy()");
+  }
+
+  /**
+   * Update the placement of the NSVisualEffectViews inside the container
+   * NSView so that they cover aRegion, and create new NSVisualEffectViews
+   * or remove existing ones as needed.
+   * @param aType   The vibrancy type to use in the region.
+   * @param aRegion The vibrant area, in device pixels.
+   */
+  void UpdateVibrantRegion(VibrancyType aType,
+                           const LayoutDeviceIntRegion& aRegion);
+
+  bool HasVibrantRegions() { return !mVibrantRegions.IsEmpty(); }
+
+  /**
+   * Return the fill color that should be drawn on top of the cleared window
+   * parts. Usually this would be drawn by -[NSVisualEffectView drawRect:].
+   * The returned color is opaque if the system-wide "Reduce transparency"
+   * preference is set.
+   */
+  NSColor* VibrancyFillColorForType(VibrancyType aType);
+
+  /**
+   * Return the font smoothing background color that should be used for text
+   * drawn on top of the vibrant window parts.
+   */
+  NSColor* VibrancyFontSmoothingBackgroundColorForType(VibrancyType aType);
+
+  /**
+   * Check whether the operating system supports vibrancy at all.
+   * You may only create a VibrancyManager instance if this returns true.
+   * @return Whether VibrancyManager can be used on this OS.
+   */
+  static bool SystemSupportsVibrancy();
+
+  /**
+   * Create an NSVisualEffectView for the specified vibrancy type. The return
+   * value is not autoreleased. We return an object of type NSView* because we
+   * compile with an SDK that does not contain a definition for
+   * NSVisualEffectView.
+   * @param aIsContainer Whether this NSView will have child views. This value
+   *                     affects hit testing: Container views will pass through
+   *                     hit testing requests to their children, and leaf views
+   *                     will be transparent to hit testing.
+   */
+  static NSView* CreateEffectView(VibrancyType aType, BOOL aIsContainer = NO);
+
+protected:
+  const nsChildView& mCoordinateConverter;
+  NSView* mContainerView;
+  nsClassHashtable<nsUint32HashKey, ViewRegion> mVibrantRegions;
+};
+
+} // namespace mozilla
+
+#endif // VibrancyManager_h
diff --git a/widget/cocoa/VibrancyManager.mm b/widget/cocoa/VibrancyManager.mm
new file mode 100644
index 0000000000..d02338eb6b
--- /dev/null
+++ b/widget/cocoa/VibrancyManager.mm
@@ -0,0 +1,244 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "VibrancyManager.h"
+#include "nsChildView.h"
+#import <objc/message.h>
+
+using namespace mozilla;
+
+void
+VibrancyManager::UpdateVibrantRegion(VibrancyType aType,
+                                     const LayoutDeviceIntRegion& aRegion)
+{
+  if (aRegion.IsEmpty()) {
+    mVibrantRegions.Remove(uint32_t(aType));
+    return;
+  }
+  auto& vr = *mVibrantRegions.LookupOrAdd(uint32_t(aType));
+  vr.UpdateRegion(aRegion, mCoordinateConverter, mContainerView, ^() {
+    return this->CreateEffectView(aType);
+  });
+}
+
+@interface NSView(CurrentFillColor)
+- (NSColor*)_currentFillColor;
+@end
+
+static NSColor*
+AdjustedColor(NSColor* aFillColor, VibrancyType aType)
+{
+  if (aType == VibrancyType::MENU && [aFillColor alphaComponent] == 1.0) {
+    // The opaque fill color that's used for the menu background when "Reduce
+    // vibrancy" is checked in the system accessibility prefs is too dark.
+    // This is probably because we're not using the right material for menus,
+    // see VibrancyManager::CreateEffectView.
+    return [NSColor colorWithDeviceWhite:0.96 alpha:1.0];
+  }
+  return aFillColor;
+}
+
+NSColor*
+VibrancyManager::VibrancyFillColorForType(VibrancyType aType)
+{
+  NSView* view = mVibrantRegions.LookupOrAdd(uint32_t(aType))->GetAnyView();
+
+  if (view && [view respondsToSelector:@selector(_currentFillColor)]) {
+    // -[NSVisualEffectView _currentFillColor] is the color that the view
+    // draws in its drawRect implementation.
+    return AdjustedColor([view _currentFillColor], aType);
+  }
+  return [NSColor whiteColor];
+}
+
+@interface NSView(FontSmoothingBackgroundColor)
+- (NSColor*)fontSmoothingBackgroundColor;
+@end
+
+NSColor*
+VibrancyManager::VibrancyFontSmoothingBackgroundColorForType(VibrancyType aType)
+{
+  NSView* view = mVibrantRegions.LookupOrAdd(uint32_t(aType))->GetAnyView();
+
+  if (view && [view respondsToSelector:@selector(fontSmoothingBackgroundColor)]) {
+    return [view fontSmoothingBackgroundColor];
+  }
+  return [NSColor clearColor];
+}
+
+static NSView*
+HitTestNil(id self, SEL _cmd, NSPoint aPoint)
+{
+  // This view must be transparent to mouse events.
+  return nil;
+}
+
+static BOOL
+AllowsVibrancyYes(id self, SEL _cmd)
+{
+  // Means that the foreground is blended using a vibrant blend mode.
+  return YES;
+}
+
+static Class
+CreateEffectViewClass(BOOL aForegroundVibrancy, BOOL aIsContainer)
+{
+  // Create a class that inherits from NSVisualEffectView and overrides the
+  // methods -[NSView hitTest:] and  -[NSVisualEffectView allowsVibrancy].
+  Class NSVisualEffectViewClass = NSClassFromString(@"NSVisualEffectView");
+  const char* className = aForegroundVibrancy
+    ? "EffectViewWithForegroundVibrancy" : "EffectViewWithoutForegroundVibrancy";
+  Class EffectViewClass = objc_allocateClassPair(NSVisualEffectViewClass, className, 0);
+  if (!aIsContainer) {
+    class_addMethod(EffectViewClass, @selector(hitTest:), (IMP)HitTestNil,
+                    "@@:{CGPoint=dd}");
+  }
+  if (aForegroundVibrancy) {
+    // Override the -[NSView allowsVibrancy] method to return YES.
+    class_addMethod(EffectViewClass, @selector(allowsVibrancy), (IMP)AllowsVibrancyYes, "I@:");
+  }
+  return EffectViewClass;
+}
+
+static id
+AppearanceForVibrancyType(VibrancyType aType)
+{
+  Class NSAppearanceClass = NSClassFromString(@"NSAppearance");
+  switch (aType) {
+    case VibrancyType::LIGHT:
+    case VibrancyType::TOOLTIP:
+    case VibrancyType::MENU:
+    case VibrancyType::HIGHLIGHTED_MENUITEM:
+    case VibrancyType::SHEET:
+    case VibrancyType::SOURCE_LIST:
+    case VibrancyType::SOURCE_LIST_SELECTION:
+    case VibrancyType::ACTIVE_SOURCE_LIST_SELECTION:
+      return [NSAppearanceClass performSelector:@selector(appearanceNamed:)
+                                     withObject:@"NSAppearanceNameVibrantLight"];
+    case VibrancyType::DARK:
+      return [NSAppearanceClass performSelector:@selector(appearanceNamed:)
+                                     withObject:@"NSAppearanceNameVibrantDark"];
+  }
+}
+
+#if !defined(MAC_OS_X_VERSION_10_10) || MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_10
+enum {
+  NSVisualEffectStateFollowsWindowActiveState,
+  NSVisualEffectStateActive,
+  NSVisualEffectStateInactive
+};
+
+enum {
+  NSVisualEffectMaterialTitlebar = 3
+};
+#endif
+
+#if !defined(MAC_OS_X_VERSION_10_11) || MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_11
+enum {
+  NSVisualEffectMaterialMenu = 5,
+  NSVisualEffectMaterialSidebar = 7
+};
+#endif
+
+static NSUInteger
+VisualEffectStateForVibrancyType(VibrancyType aType)
+{
+  switch (aType) {
+    case VibrancyType::TOOLTIP:
+    case VibrancyType::MENU:
+    case VibrancyType::HIGHLIGHTED_MENUITEM:
+    case VibrancyType::SHEET:
+      // Tooltip and menu windows are never "key" and sheets always looks
+      // active, so we need to tell the vibrancy effect to look active
+      // regardless of window state.
+      return NSVisualEffectStateActive;
+    default:
+      return NSVisualEffectStateFollowsWindowActiveState;
+  }
+}
+
+static BOOL
+HasVibrantForeground(VibrancyType aType)
+{
+  switch (aType) {
+    case VibrancyType::MENU:
+      return YES;
+    default:
+      return NO;
+  }
+}
+
+#if !defined(MAC_OS_X_VERSION_10_12) || MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_12
+enum {
+  NSVisualEffectMaterialSelection = 4
+};
+#endif
+
+@interface NSView(NSVisualEffectViewMethods)
+- (void)setState:(NSUInteger)state;
+- (void)setMaterial:(NSUInteger)material;
+- (void)setEmphasized:(BOOL)emphasized;
+@end
+
+NSView*
+VibrancyManager::CreateEffectView(VibrancyType aType, BOOL aIsContainer)
+{
+  static Class EffectViewWithoutForegroundVibrancy = CreateEffectViewClass(NO, NO);
+  static Class EffectViewWithForegroundVibrancy = CreateEffectViewClass(YES, NO);
+  static Class EffectViewContainer = CreateEffectViewClass(NO, YES);
+
+  // Pick the right NSVisualEffectView subclass for the desired vibrancy mode.
+  // For "container" views, never use foreground vibrancy, because returning
+  // YES from allowsVibrancy forces on foreground vibrancy for all descendant
+  // views which can have unintended effects.
+  Class EffectViewClass = aIsContainer
+                              ? EffectViewContainer
+                              : (HasVibrantForeground(aType) ? EffectViewWithForegroundVibrancy
+                                                             : EffectViewWithoutForegroundVibrancy);
+  NSView* effectView = [[EffectViewClass alloc] initWithFrame:NSZeroRect];
+  [effectView performSelector:@selector(setAppearance:)
+                   withObject:AppearanceForVibrancyType(aType)];
+  [effectView setState:VisualEffectStateForVibrancyType(aType)];
+
+  BOOL canUseElCapitanMaterials = nsCocoaFeatures::OnElCapitanOrLater();
+  if (aType == VibrancyType::MENU) {
+    // Before 10.11 there is no material that perfectly matches the menu
+    // look. Of all available material types, NSVisualEffectMaterialTitlebar
+    // is the one that comes closest.
+    [effectView setMaterial:canUseElCapitanMaterials ? NSVisualEffectMaterialMenu
+                                                     : NSVisualEffectMaterialTitlebar];
+  } else if (aType == VibrancyType::SOURCE_LIST && canUseElCapitanMaterials) {
+    [effectView setMaterial:NSVisualEffectMaterialSidebar];
+  } else if (aType == VibrancyType::HIGHLIGHTED_MENUITEM ||
+             aType == VibrancyType::SOURCE_LIST_SELECTION ||
+             aType == VibrancyType::ACTIVE_SOURCE_LIST_SELECTION) {
+    [effectView setMaterial:NSVisualEffectMaterialSelection];
+    if ([effectView respondsToSelector:@selector(setEmphasized:)] &&
+        aType != VibrancyType::SOURCE_LIST_SELECTION) {
+      [effectView setEmphasized:YES];
+    }
+  }
+
+  return effectView;
+}
+
+static bool
+ComputeSystemSupportsVibrancy()
+{
+#ifdef __x86_64__
+  return NSClassFromString(@"NSAppearance") &&
+      NSClassFromString(@"NSVisualEffectView");
+#else
+  // objc_allocateClassPair doesn't work in 32 bit mode, so turn off vibrancy.
+  return false;
+#endif
+}
+
+/* static */ bool
+VibrancyManager::SystemSupportsVibrancy()
+{
+  static bool supportsVibrancy = ComputeSystemSupportsVibrancy();
+  return supportsVibrancy;
+}
diff --git a/widget/cocoa/ViewRegion.h b/widget/cocoa/ViewRegion.h
new file mode 100644
index 0000000000..9ff7e6d091
--- /dev/null
+++ b/widget/cocoa/ViewRegion.h
@@ -0,0 +1,52 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef ViewRegion_h
+#define ViewRegion_h
+
+#include "Units.h"
+#include "nsTArray.h"
+
+@class NSView;
+
+namespace mozilla {
+
+/**
+ * Manages a set of NSViews to cover a LayoutDeviceIntRegion.
+ */
+class ViewRegion {
+public:
+  ~ViewRegion();
+
+  mozilla::LayoutDeviceIntRegion Region() { return mRegion; }
+
+  /**
+   * Update the region.
+   * @param aRegion  The new region.
+   * @param aCoordinateConverter  The nsChildView to use for converting
+   *   LayoutDeviceIntRect device pixel coordinates into Cocoa NSRect coordinates.
+   * @param aContainerView  The view that's going to be the superview of the
+   *   NSViews which will be created for this region.
+   * @param aViewCreationCallback  A block that instantiates new NSViews.
+   * @return  Whether or not the region changed.
+   */
+  bool UpdateRegion(const mozilla::LayoutDeviceIntRegion& aRegion,
+                    const nsChildView& aCoordinateConverter,
+                    NSView* aContainerView,
+                    NSView* (^aViewCreationCallback)());
+
+  /**
+   * Return an NSView from the region, if there is any.
+   */
+  NSView* GetAnyView() { return mViews.Length() > 0 ? mViews[0] : nil; }
+
+private:
+  mozilla::LayoutDeviceIntRegion mRegion;
+  nsTArray<NSView*> mViews;
+};
+
+} // namespace mozilla
+
+#endif // ViewRegion_h
diff --git a/widget/cocoa/ViewRegion.mm b/widget/cocoa/ViewRegion.mm
new file mode 100644
index 0000000000..455d54fdad
--- /dev/null
+++ b/widget/cocoa/ViewRegion.mm
@@ -0,0 +1,70 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ViewRegion.h"
+#import <Cocoa/Cocoa.h>
+
+using namespace mozilla;
+
+ViewRegion::~ViewRegion()
+{
+  for (size_t i = 0; i < mViews.Length(); i++) {
+    [mViews[i] removeFromSuperview];
+  }
+}
+
+bool
+ViewRegion::UpdateRegion(const LayoutDeviceIntRegion& aRegion,
+                         const nsChildView& aCoordinateConverter,
+                         NSView* aContainerView,
+                         NSView* (^aViewCreationCallback)())
+{
+  if (mRegion == aRegion) {
+    return false;
+  }
+
+  // We need to construct the required region using as many EffectViews
+  // as necessary. We try to update the geometry of existing views if
+  // possible, or create new ones or remove old ones if the number of
+  // rects in the region has changed.
+
+  nsTArray<NSView*> viewsToRecycle;
+  mViews.SwapElements(viewsToRecycle);
+  // The mViews array is now empty.
+
+  size_t i = 0;
+  for (auto iter = aRegion.RectIter();
+       !iter.Done() || i < viewsToRecycle.Length();
+       i++) {
+    if (!iter.Done()) {
+      NSView* view = nil;
+      NSRect rect = aCoordinateConverter.DevPixelsToCocoaPoints(iter.Get());
+      if (i < viewsToRecycle.Length()) {
+        view = viewsToRecycle[i];
+      } else {
+        view = aViewCreationCallback();
+        [aContainerView addSubview:view];
+
+        // Now that the view is in the view hierarchy, it'll be kept alive by
+        // its superview, so we can drop our reference.
+        [view release];
+      }
+      if (!NSEqualRects(rect, [view frame])) {
+        [view setFrame:rect];
+      }
+      [view setNeedsDisplay:YES];
+      mViews.AppendElement(view);
+      iter.Next();
+    } else {
+      // Our new region is made of fewer rects than the old region, so we can
+      // remove this view. We only have a weak reference to it, so removing it
+      // from the view hierarchy will release it.
+      [viewsToRecycle[i] removeFromSuperview];
+    }
+  }
+
+  mRegion = aRegion;
+  return true;
+}
diff --git a/widget/cocoa/WidgetTraceEvent.mm b/widget/cocoa/WidgetTraceEvent.mm
new file mode 100644
index 0000000000..7023a17ba0
--- /dev/null
+++ b/widget/cocoa/WidgetTraceEvent.mm
@@ -0,0 +1,85 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <Cocoa/Cocoa.h>
+#include "CustomCocoaEvents.h"
+#include <Foundation/NSAutoreleasePool.h>
+#include <mozilla/CondVar.h>
+#include <mozilla/Mutex.h>
+#include "mozilla/WidgetTraceEvent.h"
+
+using mozilla::CondVar;
+using mozilla::Mutex;
+using mozilla::MutexAutoLock;
+
+namespace {
+
+Mutex* sMutex = NULL;
+CondVar* sCondVar = NULL;
+bool sTracerProcessed = false;
+
+} // namespace
+
+namespace mozilla {
+
+bool InitWidgetTracing()
+{
+  sMutex = new Mutex("Event tracer thread mutex");
+  sCondVar = new CondVar(*sMutex, "Event tracer thread condvar");
+  return sMutex && sCondVar;
+}
+
+void CleanUpWidgetTracing()
+{
+  delete sMutex;
+  delete sCondVar;
+  sMutex = NULL;
+  sCondVar = NULL;
+}
+
+// This function is called from the main (UI) thread.
+void SignalTracerThread()
+{
+  if (!sMutex || !sCondVar)
+    return;
+  MutexAutoLock lock(*sMutex);
+  if (!sTracerProcessed) {
+    sTracerProcessed = true;
+    sCondVar->Notify();
+  }
+}
+
+// This function is called from the background tracer thread.
+bool FireAndWaitForTracerEvent()
+{
+  MOZ_ASSERT(sMutex && sCondVar, "Tracing not initialized!");
+  NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
+  MutexAutoLock lock(*sMutex);
+  if (sTracerProcessed) {
+    // Things are out of sync. This is likely because we're in
+    // the middle of shutting down. Just return false and hope the
+    // tracer thread is quitting anyway.
+    return false;
+  }
+
+  // Post an application-defined event to the main thread's event queue
+  // and wait for it to get processed.
+  [NSApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined
+                                      location:NSMakePoint(0,0)
+                                 modifierFlags:0
+                                     timestamp:0
+                                  windowNumber:0
+                                       context:NULL
+                                       subtype:kEventSubtypeTrace
+                                         data1:0
+                                         data2:0]
+             atStart:NO];
+  while (!sTracerProcessed)
+    sCondVar->Wait();
+  sTracerProcessed = false;
+  [pool release];
+  return true;
+}
+
+}  // namespace mozilla
diff --git a/widget/cocoa/crashtests/373122-1-inner.html b/widget/cocoa/crashtests/373122-1-inner.html
new file mode 100644
index 0000000000..5c14166b75
--- /dev/null
+++ b/widget/cocoa/crashtests/373122-1-inner.html
@@ -0,0 +1,39 @@
+<html>
+<head>
+
+<script>
+function boom()
+{
+  document.body.style.position = "fixed"
+  
+  setTimeout(boom2, 1);
+}
+
+function boom2()
+{
+  lappy = document.getElementById("lappy");
+  lappy.style.display = "none"
+
+  setTimeout(boom3, 200);
+}
+
+function boom3()
+{
+  dump("Reloading\n");
+  location.reload();
+}
+
+</script>
+
+
+</head>
+
+
+<body bgcolor="black" onload="boom()">
+
+  <span style="overflow: scroll; display: -moz-box;"></span>
+
+  <embed id="lappy" src="" width=550 height=400 TYPE="application/x-shockwave-flash" ></embed>
+ 
+</body>
+</html>
diff --git a/widget/cocoa/crashtests/373122-1.html b/widget/cocoa/crashtests/373122-1.html
new file mode 100644
index 0000000000..a57e5f4249
--- /dev/null
+++ b/widget/cocoa/crashtests/373122-1.html
@@ -0,0 +1,9 @@
+<html class="reftest-wait">
+<head>
+<script>
+setTimeout('document.documentElement.className = ""', 1000);
+</script>
+<body>
+<iframe src="373122-1-inner.html"></iframe>
+</body>
+</html>
diff --git a/widget/cocoa/crashtests/397209-1.html b/widget/cocoa/crashtests/397209-1.html
new file mode 100644
index 0000000000..554b2dac72
--- /dev/null
+++ b/widget/cocoa/crashtests/397209-1.html
@@ -0,0 +1,7 @@
+<html>
+<head>
+</head>
+<body>
+<button style="width: 8205em;"></button>
+</body>
+</html>
diff --git a/widget/cocoa/crashtests/403296-1.xhtml b/widget/cocoa/crashtests/403296-1.xhtml
new file mode 100644
index 0000000000..800eaa3558
--- /dev/null
+++ b/widget/cocoa/crashtests/403296-1.xhtml
@@ -0,0 +1,10 @@
+<html xmlns="http://www.w3.org/1999/xhtml" 
+      class="reftest-wait"  
+      style="margin: 12em; padding: 20px 10em; opacity: 0.2; font-size: 11.2px; -moz-appearance: toolbar; white-space: nowrap;"><body 
+      style="position: absolute;" 
+      onload="setTimeout(function() { document.body.removeChild(document.getElementById('tr')); document.documentElement.removeAttribute('class'); }, 30);">
+
+xxx
+yyy
+
+<tr id="tr">300</tr></body></html>
diff --git a/widget/cocoa/crashtests/419737-1.html b/widget/cocoa/crashtests/419737-1.html
new file mode 100644
index 0000000000..fe6e4532b4
--- /dev/null
+++ b/widget/cocoa/crashtests/419737-1.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html>
+<html>
+<head>
+</head>
+<body>
+<div><span style="-moz-appearance: radio; padding: 15000px;"></span></div>
+</body>
+</html>
diff --git a/widget/cocoa/crashtests/435223-1.html b/widget/cocoa/crashtests/435223-1.html
new file mode 100644
index 0000000000..1bbc27ba01
--- /dev/null
+++ b/widget/cocoa/crashtests/435223-1.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html>
+<html>
+<head>
+</head>
+<body>
+<div style="min-width: -moz-max-content;"><div style="-moz-appearance: button;"><div style="margin: 0 100%;"></div></div></div>
+</body>
+</html>
diff --git a/widget/cocoa/crashtests/444260-1.xul b/widget/cocoa/crashtests/444260-1.xul
new file mode 100644
index 0000000000..f1a84023df
--- /dev/null
+++ b/widget/cocoa/crashtests/444260-1.xul
@@ -0,0 +1,3 @@
+<window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+<hbox><button width="7788025414616">S</button></hbox>
+</window>
diff --git a/widget/cocoa/crashtests/444864-1.html b/widget/cocoa/crashtests/444864-1.html
new file mode 100644
index 0000000000..f8bac76e6a
--- /dev/null
+++ b/widget/cocoa/crashtests/444864-1.html
@@ -0,0 +1,6 @@
+<!DOCTYPE html>
+<html>
+<body>
+<div style="padding: 10px;"><input type="button" value="Go" style="letter-spacing: 331989pt;"></div>
+</body>
+</html>
diff --git a/widget/cocoa/crashtests/449111-1.html b/widget/cocoa/crashtests/449111-1.html
new file mode 100644
index 0000000000..4494591803
--- /dev/null
+++ b/widget/cocoa/crashtests/449111-1.html
@@ -0,0 +1,4 @@
+<html>
+<head></head>
+<body><div style="display: -moz-box; word-spacing: 549755813889px;"><button>T </button></div></body>
+</html>
diff --git a/widget/cocoa/crashtests/460349-1.xhtml b/widget/cocoa/crashtests/460349-1.xhtml
new file mode 100644
index 0000000000..cc9b9700c7
--- /dev/null
+++ b/widget/cocoa/crashtests/460349-1.xhtml
@@ -0,0 +1,4 @@
+<html xmlns="http://www.w3.org/1999/xhtml">
+<head></head>
+<body><div><mstyle xmlns="http://www.w3.org/1998/Math/MathML" style="-moz-appearance: button;"/></div></body>
+</html>
diff --git a/widget/cocoa/crashtests/460387-1.html b/widget/cocoa/crashtests/460387-1.html
new file mode 100644
index 0000000000..cab7e7eb32
--- /dev/null
+++ b/widget/cocoa/crashtests/460387-1.html
@@ -0,0 +1,2 @@
+<!DOCTYPE html>
+<html><head></head><body><div style="display: table; padding: 625203mm; -moz-appearance: menulist;"></div></body></html>
diff --git a/widget/cocoa/crashtests/464589-1.html b/widget/cocoa/crashtests/464589-1.html
new file mode 100644
index 0000000000..d25d92315d
--- /dev/null
+++ b/widget/cocoa/crashtests/464589-1.html
@@ -0,0 +1,20 @@
+<html>
+<head>
+<script type="text/javascript">
+
+function boom()
+{
+  var o2 = document.createElement("option");
+  document.getElementById("o1").appendChild(o2);
+  o2.style.padding = "131072cm";
+}
+
+</script>
+</head>
+
+<body onload="boom();">
+
+<select><option id="o1" style="height: 0cm;"></option></select>
+
+</body>
+</html>
diff --git a/widget/cocoa/crashtests/crashtests.list b/widget/cocoa/crashtests/crashtests.list
new file mode 100644
index 0000000000..b65fe01394
--- /dev/null
+++ b/widget/cocoa/crashtests/crashtests.list
@@ -0,0 +1,11 @@
+skip-if(!cocoaWidget) load 373122-1.html # bug 1300017
+load 397209-1.html
+load 403296-1.xhtml
+load 419737-1.html
+load 435223-1.html
+load 444260-1.xul
+load 444864-1.html
+load 449111-1.html
+load 460349-1.xhtml
+load 460387-1.html
+load 464589-1.html
diff --git a/widget/cocoa/cursors/arrowN.png b/widget/cocoa/cursors/arrowN.png
new file mode 100644
index 0000000000..5ca8ec5ac6
--- /dev/null
+++ b/widget/cocoa/cursors/arrowN.png
diff --git a/widget/cocoa/cursors/arrowN@2x.png b/widget/cocoa/cursors/arrowN@2x.png
new file mode 100644
index 0000000000..d00e87636c
--- /dev/null
+++ b/widget/cocoa/cursors/arrowN@2x.png
diff --git a/widget/cocoa/cursors/arrowS.png b/widget/cocoa/cursors/arrowS.png
new file mode 100644
index 0000000000..9b2d19e0fd
--- /dev/null
+++ b/widget/cocoa/cursors/arrowS.png
diff --git a/widget/cocoa/cursors/arrowS@2x.png b/widget/cocoa/cursors/arrowS@2x.png
new file mode 100644
index 0000000000..5d011c1fd1
--- /dev/null
+++ b/widget/cocoa/cursors/arrowS@2x.png
diff --git a/widget/cocoa/cursors/cell.png b/widget/cocoa/cursors/cell.png
new file mode 100644
index 0000000000..5284eaec57
--- /dev/null
+++ b/widget/cocoa/cursors/cell.png
diff --git a/widget/cocoa/cursors/cell@2x.png b/widget/cocoa/cursors/cell@2x.png
new file mode 100644
index 0000000000..5e6738cff7
--- /dev/null
+++ b/widget/cocoa/cursors/cell@2x.png
diff --git a/widget/cocoa/cursors/colResize.png b/widget/cocoa/cursors/colResize.png
new file mode 100644
index 0000000000..4e3e19e223
--- /dev/null
+++ b/widget/cocoa/cursors/colResize.png
diff --git a/widget/cocoa/cursors/colResize@2x.png b/widget/cocoa/cursors/colResize@2x.png
new file mode 100644
index 0000000000..6a92cf6806
--- /dev/null
+++ b/widget/cocoa/cursors/colResize@2x.png
diff --git a/widget/cocoa/cursors/help.png b/widget/cocoa/cursors/help.png
new file mode 100644
index 0000000000..5e5416b4e3
--- /dev/null
+++ b/widget/cocoa/cursors/help.png
diff --git a/widget/cocoa/cursors/help@2x.png b/widget/cocoa/cursors/help@2x.png
new file mode 100644
index 0000000000..0ac53a9733
--- /dev/null
+++ b/widget/cocoa/cursors/help@2x.png
diff --git a/widget/cocoa/cursors/move.png b/widget/cocoa/cursors/move.png
new file mode 100644
index 0000000000..1360f82277
--- /dev/null
+++ b/widget/cocoa/cursors/move.png
diff --git a/widget/cocoa/cursors/move@2x.png b/widget/cocoa/cursors/move@2x.png
new file mode 100644
index 0000000000..ad146e4863
--- /dev/null
+++ b/widget/cocoa/cursors/move@2x.png
diff --git a/widget/cocoa/cursors/rowResize.png b/widget/cocoa/cursors/rowResize.png
new file mode 100644
index 0000000000..4c16bb8bd6
--- /dev/null
+++ b/widget/cocoa/cursors/rowResize.png
diff --git a/widget/cocoa/cursors/rowResize@2x.png b/widget/cocoa/cursors/rowResize@2x.png
new file mode 100644
index 0000000000..b48f03ae0d
--- /dev/null
+++ b/widget/cocoa/cursors/rowResize@2x.png
diff --git a/widget/cocoa/cursors/sizeNE.png b/widget/cocoa/cursors/sizeNE.png
new file mode 100644
index 0000000000..f62c046575
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNE.png
diff --git a/widget/cocoa/cursors/sizeNE@2x.png b/widget/cocoa/cursors/sizeNE@2x.png
new file mode 100644
index 0000000000..98d19e9efa
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNE@2x.png
diff --git a/widget/cocoa/cursors/sizeNESW.png b/widget/cocoa/cursors/sizeNESW.png
new file mode 100644
index 0000000000..0a077fa674
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNESW.png
diff --git a/widget/cocoa/cursors/sizeNESW@2x.png b/widget/cocoa/cursors/sizeNESW@2x.png
new file mode 100644
index 0000000000..31bca3c901
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNESW@2x.png
diff --git a/widget/cocoa/cursors/sizeNS.png b/widget/cocoa/cursors/sizeNS.png
new file mode 100644
index 0000000000..0419be0af7
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNS.png
diff --git a/widget/cocoa/cursors/sizeNS@2x.png b/widget/cocoa/cursors/sizeNS@2x.png
new file mode 100644
index 0000000000..e48fd0cb3a
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNS@2x.png
diff --git a/widget/cocoa/cursors/sizeNW.png b/widget/cocoa/cursors/sizeNW.png
new file mode 100644
index 0000000000..8f5faee5f7
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNW.png
diff --git a/widget/cocoa/cursors/sizeNW@2x.png b/widget/cocoa/cursors/sizeNW@2x.png
new file mode 100644
index 0000000000..3a80e7ce91
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNW@2x.png
diff --git a/widget/cocoa/cursors/sizeNWSE.png b/widget/cocoa/cursors/sizeNWSE.png
new file mode 100644
index 0000000000..0574a584c1
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNWSE.png
diff --git a/widget/cocoa/cursors/sizeNWSE@2x.png b/widget/cocoa/cursors/sizeNWSE@2x.png
new file mode 100644
index 0000000000..9a0a276c34
--- /dev/null
+++ b/widget/cocoa/cursors/sizeNWSE@2x.png
diff --git a/widget/cocoa/cursors/sizeSE.png b/widget/cocoa/cursors/sizeSE.png
new file mode 100644
index 0000000000..6a1948f521
--- /dev/null
+++ b/widget/cocoa/cursors/sizeSE.png
diff --git a/widget/cocoa/cursors/sizeSE@2x.png b/widget/cocoa/cursors/sizeSE@2x.png
new file mode 100644
index 0000000000..7d637f4be6
--- /dev/null
+++ b/widget/cocoa/cursors/sizeSE@2x.png
diff --git a/widget/cocoa/cursors/sizeSW.png b/widget/cocoa/cursors/sizeSW.png
new file mode 100644
index 0000000000..5dd054dd46
--- /dev/null
+++ b/widget/cocoa/cursors/sizeSW.png
diff --git a/widget/cocoa/cursors/sizeSW@2x.png b/widget/cocoa/cursors/sizeSW@2x.png
new file mode 100644
index 0000000000..5ac63c25c6
--- /dev/null
+++ b/widget/cocoa/cursors/sizeSW@2x.png
diff --git a/widget/cocoa/cursors/vtIBeam.png b/widget/cocoa/cursors/vtIBeam.png
new file mode 100644
index 0000000000..ee7528c595
--- /dev/null
+++ b/widget/cocoa/cursors/vtIBeam.png
diff --git a/widget/cocoa/cursors/vtIBeam@2x.png b/widget/cocoa/cursors/vtIBeam@2x.png
new file mode 100644
index 0000000000..41c47af116
--- /dev/null
+++ b/widget/cocoa/cursors/vtIBeam@2x.png
diff --git a/widget/cocoa/cursors/zoomIn.png b/widget/cocoa/cursors/zoomIn.png
new file mode 100644
index 0000000000..275bf1c69d
--- /dev/null
+++ b/widget/cocoa/cursors/zoomIn.png
diff --git a/widget/cocoa/cursors/zoomIn@2x.png b/widget/cocoa/cursors/zoomIn@2x.png
new file mode 100644
index 0000000000..fdd3f8e71d
--- /dev/null
+++ b/widget/cocoa/cursors/zoomIn@2x.png
diff --git a/widget/cocoa/cursors/zoomOut.png b/widget/cocoa/cursors/zoomOut.png
new file mode 100644
index 0000000000..19d2d89125
--- /dev/null
+++ b/widget/cocoa/cursors/zoomOut.png
diff --git a/widget/cocoa/cursors/zoomOut@2x.png b/widget/cocoa/cursors/zoomOut@2x.png
new file mode 100644
index 0000000000..0ed46ce75e
--- /dev/null
+++ b/widget/cocoa/cursors/zoomOut@2x.png
diff --git a/widget/cocoa/moz.build b/widget/cocoa/moz.build
new file mode 100644
index 0000000000..c4f887297d
--- /dev/null
+++ b/widget/cocoa/moz.build
@@ -0,0 +1,140 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+XPIDL_SOURCES += [
+    'nsPIWidgetCocoa.idl',
+]
+
+XPIDL_MODULE = 'widget_cocoa'
+
+EXPORTS += [
+    'mozView.h',
+    'nsBidiKeyboard.h',
+    'nsChangeObserver.h',
+    'nsCocoaDebugUtils.h',
+    'nsCocoaFeatures.h',
+    'nsCocoaUtils.h',
+]
+
+UNIFIED_SOURCES += [
+    'ComplexTextInputPanel.mm',
+    'GfxInfo.mm',
+    'NativeKeyBindings.mm',
+    'nsAppShell.mm',
+    'nsBidiKeyboard.mm',
+    'nsCocoaFeatures.mm',
+    'nsCocoaUtils.mm',
+    'nsCocoaWindow.mm',
+    'nsColorPicker.mm',
+    'nsCursorManager.mm',
+    'nsDeviceContextSpecX.mm',
+    'nsFilePicker.mm',
+    'nsIdleServiceX.mm',
+    'nsLookAndFeel.mm',
+    'nsMacCursor.mm',
+    'nsMacDockSupport.mm',
+    'nsMacWebAppUtils.mm',
+    'nsMenuBarX.mm',
+    'nsMenuGroupOwnerX.mm',
+    'nsMenuItemIconX.mm',
+    'nsMenuItemX.mm',
+    'nsMenuUtilsX.mm',
+    'nsMenuX.mm',
+    'nsPrintDialogX.mm',
+    'nsPrintOptionsX.mm',
+    'nsPrintSettingsX.mm',
+    'nsScreenCocoa.mm',
+    'nsScreenManagerCocoa.mm',
+    'nsSound.mm',
+    'nsStandaloneNativeMenu.mm',
+    'nsSystemStatusBarCocoa.mm',
+    'nsToolkit.mm',
+    'nsWidgetFactory.mm',
+    'nsWindowMap.mm',
+    'OSXNotificationCenter.mm',
+    'RectTextureImage.mm',
+    'SwipeTracker.mm',
+    'TextInputHandler.mm',
+    'VibrancyManager.mm',
+    'ViewRegion.mm',
+    'WidgetTraceEvent.mm',
+]
+
+# These files cannot be built in unified mode because they cause symbol conflicts
+SOURCES += [
+    'nsChildView.mm',
+    'nsClipboard.mm',
+    'nsCocoaDebugUtils.mm',
+    'nsDragService.mm',
+    'nsNativeThemeCocoa.mm',
+]
+
+if not CONFIG['RELEASE_OR_BETA'] or CONFIG['MOZ_DEBUG']:
+    SOURCES += [
+        'nsSandboxViolationSink.mm',
+    ]
+
+include('/ipc/chromium/chromium-config.mozbuild')
+
+# XXX: We should fix these warnings.
+ALLOW_COMPILER_WARNINGS = True
+
+FINAL_LIBRARY = 'xul'
+LOCAL_INCLUDES += [
+    '/layout/forms',
+    '/layout/generic',
+    '/layout/style',
+    '/layout/xul',
+    '/widget',
+]
+
+RESOURCE_FILES.cursors += [
+    'cursors/arrowN.png',
+    'cursors/arrowN@2x.png',
+    'cursors/arrowS.png',
+    'cursors/arrowS@2x.png',
+    'cursors/cell.png',
+    'cursors/cell@2x.png',
+    'cursors/colResize.png',
+    'cursors/colResize@2x.png',
+    'cursors/help.png',
+    'cursors/help@2x.png',
+    'cursors/move.png',
+    'cursors/move@2x.png',
+    'cursors/rowResize.png',
+    'cursors/rowResize@2x.png',
+    'cursors/sizeNE.png',
+    'cursors/sizeNE@2x.png',
+    'cursors/sizeNESW.png',
+    'cursors/sizeNESW@2x.png',
+    'cursors/sizeNS.png',
+    'cursors/sizeNS@2x.png',
+    'cursors/sizeNW.png',
+    'cursors/sizeNW@2x.png',
+    'cursors/sizeNWSE.png',
+    'cursors/sizeNWSE@2x.png',
+    'cursors/sizeSE.png',
+    'cursors/sizeSE@2x.png',
+    'cursors/sizeSW.png',
+    'cursors/sizeSW@2x.png',
+    'cursors/vtIBeam.png',
+    'cursors/vtIBeam@2x.png',
+    'cursors/zoomIn.png',
+    'cursors/zoomIn@2x.png',
+    'cursors/zoomOut.png',
+    'cursors/zoomOut@2x.png',
+]
+
+# These resources go in $(DIST)/bin/res/MainMenu.nib, but we can't use a magic
+# RESOURCE_FILES.MainMenu.nib attribute, since that would put the files in
+# $(DIST)/bin/res/MainMenu/nib. Instead, we call __setattr__ directly to create
+# an attribute with the correct name.
+RESOURCE_FILES.__setattr__('MainMenu.nib', [
+    'resources/MainMenu.nib/classes.nib',
+    'resources/MainMenu.nib/info.nib',
+    'resources/MainMenu.nib/keyedobjects.nib',
+])
+
+CXXFLAGS += CONFIG['TK_CFLAGS']
diff --git a/widget/cocoa/mozView.h b/widget/cocoa/mozView.h
new file mode 100644
index 0000000000..bd054893ba
--- /dev/null
+++ b/widget/cocoa/mozView.h
@@ -0,0 +1,62 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozView_h_
+#define mozView_h_
+
+#undef DARWIN
+#import <Cocoa/Cocoa.h>
+class nsIWidget;
+
+namespace mozilla {
+namespace widget{
+class TextInputHandler;
+} // namespace widget
+} // namespace mozilla
+
+// A protocol listing all the methods that an object which wants
+// to live in gecko's widget hierarchy must implement. |nsChildView|
+// makes assumptions that any NSView with which it comes in contact will
+// implement this protocol.
+@protocol mozView
+
+  // aHandler is Gecko's default text input handler:  It implements the
+  // NSTextInput protocol to handle key events.  Don't make aHandler a
+  // strong reference -- that causes a memory leak.
+- (void)installTextInputHandler:(mozilla::widget::TextInputHandler*)aHandler;
+- (void)uninstallTextInputHandler;
+
+  // access the nsIWidget associated with this view. DOES NOT ADDREF.
+- (nsIWidget*)widget;
+
+  // return a context menu for this view
+- (NSMenu*)contextMenu;
+
+  // called when our corresponding Gecko view goes away
+- (void)widgetDestroyed;
+
+- (BOOL)isDragInProgress;
+
+  // Checks whether the view is first responder or not
+- (BOOL)isFirstResponder;
+
+  // Call when you dispatch an event which may cause to open context menu.
+- (void)maybeInitContextMenuTracking;
+
+@end
+
+// An informal protocol implemented by the NSWindow of the host application.
+// 
+// It's used to prevent re-entrant calls to -makeKeyAndOrderFront: when gecko
+// focus/activate events propagate out to the embedder's
+// nsIEmbeddingSiteWindow::SetFocus implementation.
+@interface NSObject(mozWindow)
+
+- (BOOL)suppressMakeKeyFront;
+- (void)setSuppressMakeKeyFront:(BOOL)inSuppress;
+
+@end
+
+#endif // mozView_h_
diff --git a/widget/cocoa/nsAppShell.h b/widget/cocoa/nsAppShell.h
new file mode 100644
index 0000000000..b7836b6391
--- /dev/null
+++ b/widget/cocoa/nsAppShell.h
@@ -0,0 +1,71 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Runs the main native Cocoa run loop, interrupting it as needed to process
+ * Gecko events.
+ */
+
+#ifndef nsAppShell_h_
+#define nsAppShell_h_
+
+#include "nsBaseAppShell.h"
+#include "nsTArray.h"
+
+// GeckoNSApplication
+//
+// Subclass of NSApplication for filtering out certain events.
+@interface GeckoNSApplication : NSApplication
+{
+}
+@end
+
+@class AppShellDelegate;
+
+class nsAppShell : public nsBaseAppShell
+{
+public:
+  NS_IMETHOD ResumeNative(void);
+
+  nsAppShell();
+
+  nsresult Init();
+
+  NS_IMETHOD Run(void);
+  NS_IMETHOD Exit(void);
+  NS_IMETHOD OnProcessNextEvent(nsIThreadInternal *aThread, bool aMayWait);
+  NS_IMETHOD AfterProcessNextEvent(nsIThreadInternal *aThread,
+                                   bool aEventWasProcessed);
+
+  // public only to be visible to Objective-C code that must call it
+  void WillTerminate();
+
+protected:
+  virtual ~nsAppShell();
+
+  virtual void ScheduleNativeEventCallback();
+  virtual bool ProcessNextNativeEvent(bool aMayWait);
+
+  static void ProcessGeckoEvents(void* aInfo);
+
+protected:
+  CFMutableArrayRef  mAutoreleasePools;
+
+  AppShellDelegate*  mDelegate;
+  CFRunLoopRef       mCFRunLoop;
+  CFRunLoopSourceRef mCFRunLoopSource;
+
+  bool               mRunningEventLoop;
+  bool               mStarted;
+  bool               mTerminated;
+  bool               mSkippedNativeCallback;
+  bool               mRunningCocoaEmbedded;
+
+  int32_t            mNativeEventCallbackDepth;
+  // Can be set from different threads, so must be modified atomically
+  int32_t            mNativeEventScheduledDepth;
+};
+
+#endif // nsAppShell_h_
diff --git a/widget/cocoa/nsAppShell.mm b/widget/cocoa/nsAppShell.mm
new file mode 100644
index 0000000000..33ce8e742a
--- /dev/null
+++ b/widget/cocoa/nsAppShell.mm
@@ -0,0 +1,907 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Runs the main native Cocoa run loop, interrupting it as needed to process
+ * Gecko events.
+ */
+
+#import <Cocoa/Cocoa.h>
+
+#include "CustomCocoaEvents.h"
+#include "mozilla/WidgetTraceEvent.h"
+#include "nsAppShell.h"
+#include "nsCOMPtr.h"
+#include "nsIFile.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsString.h"
+#include "nsIRollupListener.h"
+#include "nsIWidget.h"
+#include "nsThreadUtils.h"
+#include "nsIWindowMediator.h"
+#include "nsServiceManagerUtils.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIWebBrowserChrome.h"
+#include "nsObjCExceptions.h"
+#include "nsCocoaFeatures.h"
+#include "nsCocoaUtils.h"
+#include "nsChildView.h"
+#include "nsToolkit.h"
+#include "TextInputHandler.h"
+#include "mozilla/HangMonitor.h"
+#include "GeckoProfiler.h"
+#include "pratom.h"
+#if !defined(RELEASE_OR_BETA) || defined(DEBUG)
+#include "nsSandboxViolationSink.h"
+#endif
+
+#include <IOKit/pwr_mgt/IOPMLib.h>
+#include "nsIDOMWakeLockListener.h"
+#include "nsIPowerManagerService.h"
+
+using namespace mozilla::widget;
+
+// A wake lock listener that disables screen saver when requested by
+// Gecko. For example when we're playing video in a foreground tab we
+// don't want the screen saver to turn on.
+
+class MacWakeLockListener final : public nsIDOMMozWakeLockListener {
+public:
+  NS_DECL_ISUPPORTS;
+
+private:
+  ~MacWakeLockListener() {}
+
+  IOPMAssertionID mAssertionID = kIOPMNullAssertionID;
+
+  NS_IMETHOD Callback(const nsAString& aTopic, const nsAString& aState) override {
+    if (!aTopic.EqualsASCII("screen")) {
+      return NS_OK;
+    }
+    // Note the wake lock code ensures that we're not sent duplicate
+    // "locked-foreground" notifications when multiple wake locks are held.
+    if (aState.EqualsASCII("locked-foreground")) {
+      // Prevent screen saver.
+      CFStringRef cf_topic =
+        ::CFStringCreateWithCharacters(kCFAllocatorDefault,
+                                       reinterpret_cast<const UniChar*>
+                                         (aTopic.Data()),
+                                       aTopic.Length());
+      IOReturn success =
+        ::IOPMAssertionCreateWithName(kIOPMAssertionTypeNoDisplaySleep,
+                                      kIOPMAssertionLevelOn,
+                                      cf_topic,
+                                      &mAssertionID);
+      CFRelease(cf_topic);
+      if (success != kIOReturnSuccess) {
+        NS_WARNING("failed to disable screensaver");
+      }
+    } else {
+      // Re-enable screen saver.
+      NS_WARNING("Releasing screensaver");
+      if (mAssertionID != kIOPMNullAssertionID) {
+        IOReturn result = ::IOPMAssertionRelease(mAssertionID);
+        if (result != kIOReturnSuccess) {
+          NS_WARNING("failed to release screensaver");
+        }
+      }
+    }
+    return NS_OK;
+  }
+}; // MacWakeLockListener
+
+// defined in nsCocoaWindow.mm
+extern int32_t             gXULModalLevel;
+
+static bool gAppShellMethodsSwizzled = false;
+
+@implementation GeckoNSApplication
+
+- (void)sendEvent:(NSEvent *)anEvent
+{
+  mozilla::HangMonitor::NotifyActivity();
+  if ([anEvent type] == NSApplicationDefined &&
+      [anEvent subtype] == kEventSubtypeTrace) {
+    mozilla::SignalTracerThread();
+    return;
+  }
+  [super sendEvent:anEvent];
+}
+
+#if defined(MAC_OS_X_VERSION_10_12) && \
+    MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_12 && \
+    __LP64__
+// 10.12 changed `mask` to NSEventMask (unsigned long long) for x86_64 builds.
+- (NSEvent*)nextEventMatchingMask:(NSEventMask)mask
+#else
+- (NSEvent*)nextEventMatchingMask:(NSUInteger)mask
+#endif
+                        untilDate:(NSDate*)expiration
+                           inMode:(NSString*)mode
+                          dequeue:(BOOL)flag
+{
+  if (expiration) {
+    mozilla::HangMonitor::Suspend();
+  }
+  NSEvent* nextEvent = [super nextEventMatchingMask:mask
+                        untilDate:expiration inMode:mode dequeue:flag];
+  if (expiration) {
+    mozilla::HangMonitor::NotifyActivity();
+  }
+  return nextEvent;
+}
+
+@end
+
+// AppShellDelegate
+//
+// Cocoa bridge class.  An object of this class is registered to receive
+// notifications.
+//
+@interface AppShellDelegate : NSObject
+{
+  @private
+    nsAppShell* mAppShell;
+}
+
+- (id)initWithAppShell:(nsAppShell*)aAppShell;
+- (void)applicationWillTerminate:(NSNotification*)aNotification;
+- (void)beginMenuTracking:(NSNotification*)aNotification;
+@end
+
+// nsAppShell implementation
+
+NS_IMETHODIMP
+nsAppShell::ResumeNative(void)
+{
+  nsresult retval = nsBaseAppShell::ResumeNative();
+  if (NS_SUCCEEDED(retval) && (mSuspendNativeCount == 0) &&
+      mSkippedNativeCallback)
+  {
+    mSkippedNativeCallback = false;
+    ScheduleNativeEventCallback();
+  }
+  return retval;
+}
+
+nsAppShell::nsAppShell()
+: mAutoreleasePools(nullptr)
+, mDelegate(nullptr)
+, mCFRunLoop(NULL)
+, mCFRunLoopSource(NULL)
+, mRunningEventLoop(false)
+, mStarted(false)
+, mTerminated(false)
+, mSkippedNativeCallback(false)
+, mNativeEventCallbackDepth(0)
+, mNativeEventScheduledDepth(0)
+{
+  // A Cocoa event loop is running here if (and only if) we've been embedded
+  // by a Cocoa app.
+  mRunningCocoaEmbedded = [NSApp isRunning] ? true : false;
+}
+
+nsAppShell::~nsAppShell()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mCFRunLoop) {
+    if (mCFRunLoopSource) {
+      ::CFRunLoopRemoveSource(mCFRunLoop, mCFRunLoopSource,
+                              kCFRunLoopCommonModes);
+      ::CFRelease(mCFRunLoopSource);
+    }
+    ::CFRelease(mCFRunLoop);
+  }
+
+  if (mAutoreleasePools) {
+    NS_ASSERTION(::CFArrayGetCount(mAutoreleasePools) == 0,
+                 "nsAppShell destroyed without popping all autorelease pools");
+    ::CFRelease(mAutoreleasePools);
+  }
+
+  [mDelegate release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK
+}
+
+NS_IMPL_ISUPPORTS(MacWakeLockListener, nsIDOMMozWakeLockListener)
+mozilla::StaticRefPtr<MacWakeLockListener> sWakeLockListener;
+
+static void
+AddScreenWakeLockListener()
+{
+  nsCOMPtr<nsIPowerManagerService> sPowerManagerService = do_GetService(
+                                                          POWERMANAGERSERVICE_CONTRACTID);
+  if (sPowerManagerService) {
+    sWakeLockListener = new MacWakeLockListener();
+    sPowerManagerService->AddWakeLockListener(sWakeLockListener);
+  } else {
+    NS_WARNING("Failed to retrieve PowerManagerService, wakelocks will be broken!");
+  }
+}
+
+static void
+RemoveScreenWakeLockListener()
+{
+  nsCOMPtr<nsIPowerManagerService> sPowerManagerService = do_GetService(
+                                                          POWERMANAGERSERVICE_CONTRACTID);
+  if (sPowerManagerService) {
+    sPowerManagerService->RemoveWakeLockListener(sWakeLockListener);
+    sPowerManagerService = nullptr;
+    sWakeLockListener = nullptr;
+  }
+}
+
+// An undocumented CoreGraphics framework method, present in the same form
+// since at least OS X 10.5.
+extern "C" CGError CGSSetDebugOptions(int options);
+
+// Init
+//
+// Loads the nib (see bug 316076c21) and sets up the CFRunLoopSource used to
+// interrupt the main native run loop.
+//
+// public
+nsresult
+nsAppShell::Init()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // No event loop is running yet (unless an embedding app that uses
+  // NSApplicationMain() is running).
+  NSAutoreleasePool* localPool = [[NSAutoreleasePool alloc] init];
+
+  // mAutoreleasePools is used as a stack of NSAutoreleasePool objects created
+  // by |this|.  CFArray is used instead of NSArray because NSArray wants to
+  // retain each object you add to it, and you can't retain an
+  // NSAutoreleasePool.
+  mAutoreleasePools = ::CFArrayCreateMutable(nullptr, 0, nullptr);
+  NS_ENSURE_STATE(mAutoreleasePools);
+
+  // Get the path of the nib file, which lives in the GRE location
+  nsCOMPtr<nsIFile> nibFile;
+  nsresult rv = NS_GetSpecialDirectory(NS_GRE_DIR, getter_AddRefs(nibFile));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nibFile->AppendNative(NS_LITERAL_CSTRING("res"));
+  nibFile->AppendNative(NS_LITERAL_CSTRING("MainMenu.nib"));
+
+  nsAutoCString nibPath;
+  rv = nibFile->GetNativePath(nibPath);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // This call initializes NSApplication unless:
+  // 1) we're using xre -- NSApp's already been initialized by
+  //    MacApplicationDelegate.mm's EnsureUseCocoaDockAPI().
+  // 2) an embedding app that uses NSApplicationMain() is running -- NSApp's
+  //    already been initialized and its main run loop is already running.
+  [NSBundle loadNibFile:
+                     [NSString stringWithUTF8String:(const char*)nibPath.get()]
+      externalNameTable:
+           [NSDictionary dictionaryWithObject:[GeckoNSApplication sharedApplication]
+                                       forKey:@"NSOwner"]
+               withZone:NSDefaultMallocZone()];
+
+  mDelegate = [[AppShellDelegate alloc] initWithAppShell:this];
+  NS_ENSURE_STATE(mDelegate);
+
+  // Add a CFRunLoopSource to the main native run loop.  The source is
+  // responsible for interrupting the run loop when Gecko events are ready.
+
+  mCFRunLoop = [[NSRunLoop currentRunLoop] getCFRunLoop];
+  NS_ENSURE_STATE(mCFRunLoop);
+  ::CFRetain(mCFRunLoop);
+
+  CFRunLoopSourceContext context;
+  bzero(&context, sizeof(context));
+  // context.version = 0;
+  context.info = this;
+  context.perform = ProcessGeckoEvents;
+  
+  mCFRunLoopSource = ::CFRunLoopSourceCreate(kCFAllocatorDefault, 0, &context);
+  NS_ENSURE_STATE(mCFRunLoopSource);
+
+  ::CFRunLoopAddSource(mCFRunLoop, mCFRunLoopSource, kCFRunLoopCommonModes);
+
+  rv = nsBaseAppShell::Init();
+
+  if (!gAppShellMethodsSwizzled) {
+    // We should only replace the original terminate: method if we're not
+    // running in a Cocoa embedder. See bug 604901.
+    if (!mRunningCocoaEmbedded) {
+      nsToolkit::SwizzleMethods([NSApplication class], @selector(terminate:),
+                                @selector(nsAppShell_NSApplication_terminate:));
+    }
+    gAppShellMethodsSwizzled = true;
+  }
+
+  if (nsCocoaFeatures::OnYosemiteOrLater()) {
+    // Explicitly turn off CGEvent logging.  This works around bug 1092855.
+    // If there are already CGEvents in the log, turning off logging also
+    // causes those events to be written to disk.  But at this point no
+    // CGEvents have yet been processed.  CGEvents are events (usually
+    // input events) pulled from the WindowServer.  An option of 0x80000008
+    // turns on CGEvent logging.
+    CGSSetDebugOptions(0x80000007);
+  }
+
+#if !defined(RELEASE_OR_BETA) || defined(DEBUG)
+  if (Preferences::GetBool("security.sandbox.mac.track.violations", false)) {
+    nsSandboxViolationSink::Start();
+  }
+#endif
+
+  [localPool release];
+
+  return rv;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// ProcessGeckoEvents
+//
+// The "perform" target of mCFRunLoop, called when mCFRunLoopSource is
+// signalled from ScheduleNativeEventCallback.
+//
+// Arrange for Gecko events to be processed on demand (in response to a call
+// to ScheduleNativeEventCallback(), if processing of Gecko events via "native
+// methods" hasn't been suspended).  This happens in NativeEventCallback().
+//
+// protected static
+void
+nsAppShell::ProcessGeckoEvents(void* aInfo)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+  PROFILER_LABEL("Events", "ProcessGeckoEvents",
+    js::ProfileEntry::Category::EVENTS);
+
+  nsAppShell* self = static_cast<nsAppShell*> (aInfo);
+
+  if (self->mRunningEventLoop) {
+    self->mRunningEventLoop = false;
+
+    // The run loop may be sleeping -- [NSRunLoop runMode:...]
+    // won't return until it's given a reason to wake up.  Awaken it by
+    // posting a bogus event.  There's no need to make the event
+    // presentable.
+    //
+    // But _don't_ set windowNumber to '-1' -- that can lead to nasty
+    // weirdness like bmo bug 397039 (a crash in [NSApp sendEvent:] on one of
+    // these fake events, because the -1 has gotten changed into the number
+    // of an actual NSWindow object, and that NSWindow object has just been
+    // destroyed).  Setting windowNumber to '0' seems to work fine -- this
+    // seems to prevent the OS from ever trying to associate our bogus event
+    // with a particular NSWindow object.
+    [NSApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined
+                                        location:NSMakePoint(0,0)
+                                   modifierFlags:0
+                                       timestamp:0
+                                    windowNumber:0
+                                         context:NULL
+                                         subtype:kEventSubtypeNone
+                                           data1:0
+                                           data2:0]
+             atStart:NO];
+  }
+
+  if (self->mSuspendNativeCount <= 0) {
+    ++self->mNativeEventCallbackDepth;
+    self->NativeEventCallback();
+    --self->mNativeEventCallbackDepth;
+  } else {
+    self->mSkippedNativeCallback = true;
+  }
+
+  // Still needed to avoid crashes on quit in most Mochitests.
+  [NSApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined
+                                      location:NSMakePoint(0,0)
+                                 modifierFlags:0
+                                     timestamp:0
+                                  windowNumber:0
+                                       context:NULL
+                                       subtype:kEventSubtypeNone
+                                         data1:0
+                                         data2:0]
+           atStart:NO];
+
+  // Normally every call to ScheduleNativeEventCallback() results in
+  // exactly one call to ProcessGeckoEvents().  So each Release() here
+  // normally balances exactly one AddRef() in ScheduleNativeEventCallback().
+  // But if Exit() is called just after ScheduleNativeEventCallback(), the
+  // corresponding call to ProcessGeckoEvents() will never happen.  We check
+  // for this possibility in two different places -- here and in Exit()
+  // itself.  If we find here that Exit() has been called (that mTerminated
+  // is true), it's because we've been called recursively, that Exit() was
+  // called from self->NativeEventCallback() above, and that we're unwinding
+  // the recursion.  In this case we'll never be called again, and we balance
+  // here any extra calls to ScheduleNativeEventCallback().
+  //
+  // When ProcessGeckoEvents() is called recursively, it's because of a
+  // call to ScheduleNativeEventCallback() from NativeEventCallback().  We
+  // balance the "extra" AddRefs here (rather than always in Exit()) in order
+  // to ensure that 'self' stays alive until the end of this method.  We also
+  // make sure not to finish the balancing until all the recursion has been
+  // unwound.
+  if (self->mTerminated) {
+    int32_t releaseCount = 0;
+    if (self->mNativeEventScheduledDepth > self->mNativeEventCallbackDepth) {
+      releaseCount = PR_ATOMIC_SET(&self->mNativeEventScheduledDepth,
+                                   self->mNativeEventCallbackDepth);
+    }
+    while (releaseCount-- > self->mNativeEventCallbackDepth)
+      self->Release();
+  } else {
+    // As best we can tell, every call to ProcessGeckoEvents() is triggered
+    // by a call to ScheduleNativeEventCallback().  But we've seen a few
+    // (non-reproducible) cases of double-frees that *might* have been caused
+    // by spontaneous calls (from the OS) to ProcessGeckoEvents().  So we
+    // deal with that possibility here.
+    if (PR_ATOMIC_DECREMENT(&self->mNativeEventScheduledDepth) < 0) {
+      PR_ATOMIC_SET(&self->mNativeEventScheduledDepth, 0);
+      NS_WARNING("Spontaneous call to ProcessGeckoEvents()!");
+    } else {
+      self->Release();
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// WillTerminate
+//
+// Called by the AppShellDelegate when an NSApplicationWillTerminate
+// notification is posted.  After this method is called, native events should
+// no longer be processed.  The NSApplicationWillTerminate notification is
+// only posted when [NSApp terminate:] is called, which doesn't happen on a
+// "normal" application quit.
+//
+// public
+void
+nsAppShell::WillTerminate()
+{
+  if (mTerminated)
+    return;
+
+  // Make sure that the nsAppExitEvent posted by nsAppStartup::Quit() (called
+  // from [MacApplicationDelegate applicationShouldTerminate:]) gets run.
+  NS_ProcessPendingEvents(NS_GetCurrentThread());
+
+  mTerminated = true;
+}
+
+// ScheduleNativeEventCallback
+//
+// Called (possibly on a non-main thread) when Gecko has an event that
+// needs to be processed.  The Gecko event needs to be processed on the
+// main thread, so the native run loop must be interrupted.
+//
+// In nsBaseAppShell.cpp, the mNativeEventPending variable is used to
+// ensure that ScheduleNativeEventCallback() is called no more than once
+// per call to NativeEventCallback().  ProcessGeckoEvents() can skip its
+// call to NativeEventCallback() if processing of Gecko events by native
+// means is suspended (using nsIAppShell::SuspendNative()), which will
+// suspend calls from nsBaseAppShell::OnDispatchedEvent() to
+// ScheduleNativeEventCallback().  But when Gecko event processing by
+// native means is resumed (in ResumeNative()), an extra call is made to
+// ScheduleNativeEventCallback() (from ResumeNative()).  This triggers
+// another call to ProcessGeckoEvents(), which calls NativeEventCallback(),
+// and nsBaseAppShell::OnDispatchedEvent() resumes calling
+// ScheduleNativeEventCallback().
+//
+// protected virtual
+void
+nsAppShell::ScheduleNativeEventCallback()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mTerminated)
+    return;
+
+  // Each AddRef() here is normally balanced by exactly one Release() in
+  // ProcessGeckoEvents().  But there are exceptions, for which see
+  // ProcessGeckoEvents() and Exit().
+  NS_ADDREF_THIS();
+  PR_ATOMIC_INCREMENT(&mNativeEventScheduledDepth);
+
+  // This will invoke ProcessGeckoEvents on the main thread.
+  ::CFRunLoopSourceSignal(mCFRunLoopSource);
+  ::CFRunLoopWakeUp(mCFRunLoop);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Undocumented Cocoa Event Manager function, present in the same form since
+// at least OS X 10.6.
+extern "C" EventAttributes GetEventAttributes(EventRef inEvent);
+
+// ProcessNextNativeEvent
+//
+// If aMayWait is false, process a single native event.  If it is true, run
+// the native run loop until stopped by ProcessGeckoEvents.
+//
+// Returns true if more events are waiting in the native event queue.
+//
+// protected virtual
+bool
+nsAppShell::ProcessNextNativeEvent(bool aMayWait)
+{
+  bool moreEvents = false;
+
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  bool eventProcessed = false;
+  NSString* currentMode = nil;
+
+  if (mTerminated)
+    return false;
+
+  bool wasRunningEventLoop = mRunningEventLoop;
+  mRunningEventLoop = aMayWait;
+  NSDate* waitUntil = nil;
+  if (aMayWait)
+    waitUntil = [NSDate distantFuture];
+
+  NSRunLoop* currentRunLoop = [NSRunLoop currentRunLoop];
+
+  EventQueueRef currentEventQueue = GetCurrentEventQueue();
+  EventTargetRef eventDispatcherTarget = GetEventDispatcherTarget();
+
+  if (aMayWait) {
+    mozilla::HangMonitor::Suspend();
+  }
+
+  // Only call -[NSApp sendEvent:] (and indirectly send user-input events to
+  // Gecko) if aMayWait is true.  Tbis ensures most calls to -[NSApp
+  // sendEvent:] happen under nsAppShell::Run(), at the lowest level of
+  // recursion -- thereby making it less likely Gecko will process user-input
+  // events in the wrong order or skip some of them.  It also avoids eating
+  // too much CPU in nsBaseAppShell::OnProcessNextEvent() (which calls
+  // us) -- thereby avoiding the starvation of nsIRunnable events in
+  // nsThread::ProcessNextEvent().  For more information see bug 996848.
+  do {
+    // No autorelease pool is provided here, because OnProcessNextEvent
+    // and AfterProcessNextEvent are responsible for maintaining it.
+    NS_ASSERTION(mAutoreleasePools && ::CFArrayGetCount(mAutoreleasePools),
+                 "No autorelease pool for native event");
+
+    if (aMayWait) {
+      currentMode = [currentRunLoop currentMode];
+      if (!currentMode)
+        currentMode = NSDefaultRunLoopMode;
+      NSEvent *nextEvent = [NSApp nextEventMatchingMask:NSAnyEventMask
+                                              untilDate:waitUntil
+                                                 inMode:currentMode
+                                                dequeue:YES];
+      if (nextEvent) {
+        mozilla::HangMonitor::NotifyActivity();
+        [NSApp sendEvent:nextEvent];
+        eventProcessed = true;
+      }
+    } else {
+      // AcquireFirstMatchingEventInQueue() doesn't spin the (native) event
+      // loop, though it does queue up any newly available events from the
+      // window server.
+      EventRef currentEvent = AcquireFirstMatchingEventInQueue(currentEventQueue, 0, NULL,
+                                                               kEventQueueOptionsNone);
+      if (!currentEvent) {
+        continue;
+      }
+      EventAttributes attrs = GetEventAttributes(currentEvent);
+      UInt32 eventKind = GetEventKind(currentEvent);
+      UInt32 eventClass = GetEventClass(currentEvent);
+      bool osCocoaEvent =
+        ((eventClass == 'appl') || (eventClass == kEventClassAppleEvent) ||
+         ((eventClass == 'cgs ') && (eventKind != NSApplicationDefined)));
+      // If attrs is kEventAttributeUserEvent or kEventAttributeMonitored
+      // (i.e. a user input event), we shouldn't process it here while
+      // aMayWait is false.  Likewise if currentEvent will eventually be
+      // turned into an OS-defined Cocoa event, or otherwise needs AppKit
+      // processing.  Doing otherwise risks doing too much work here, and
+      // preventing the event from being properly processed by the AppKit
+      // framework.
+      if ((attrs != kEventAttributeNone) || osCocoaEvent) {
+        // Since we can't process the next event here (while aMayWait is false),
+        // we want moreEvents to be false on return.
+        eventProcessed = false;
+        // This call to ReleaseEvent() matches a call to RetainEvent() in
+        // AcquireFirstMatchingEventInQueue() above.
+        ReleaseEvent(currentEvent);
+        break;
+      }
+      // This call to RetainEvent() matches a call to ReleaseEvent() in
+      // RemoveEventFromQueue() below.
+      RetainEvent(currentEvent);
+      RemoveEventFromQueue(currentEventQueue, currentEvent);
+      SendEventToEventTarget(currentEvent, eventDispatcherTarget);
+      // This call to ReleaseEvent() matches a call to RetainEvent() in
+      // AcquireFirstMatchingEventInQueue() above.
+      ReleaseEvent(currentEvent);
+      eventProcessed = true;
+    }
+  } while (mRunningEventLoop);
+
+  if (eventProcessed) {
+    moreEvents =
+      (AcquireFirstMatchingEventInQueue(currentEventQueue, 0, NULL,
+                                        kEventQueueOptionsNone) != NULL);
+  }
+
+  mRunningEventLoop = wasRunningEventLoop;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+
+  if (!moreEvents) {
+    nsChildView::UpdateCurrentInputEventCount();
+  }
+
+  return moreEvents;
+}
+
+// Run
+//
+// Overrides the base class's Run() method to call [NSApp run] (which spins
+// the native run loop until the application quits).  Since (unlike the base
+// class's Run() method) we don't process any Gecko events here, they need
+// to be processed elsewhere (in NativeEventCallback(), called from
+// ProcessGeckoEvents()).
+//
+// Camino called [NSApp run] on its own (via NSApplicationMain()), and so
+// didn't call nsAppShell::Run().
+//
+// public
+NS_IMETHODIMP
+nsAppShell::Run(void)
+{
+  NS_ASSERTION(!mStarted, "nsAppShell::Run() called multiple times");
+  if (mStarted || mTerminated)
+    return NS_OK;
+
+  mStarted = true;
+
+  AddScreenWakeLockListener();
+
+  NS_OBJC_TRY_ABORT([NSApp run]);
+
+  RemoveScreenWakeLockListener();
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppShell::Exit(void)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // This method is currently called more than once -- from (according to
+  // mento) an nsAppExitEvent dispatched by nsAppStartup::Quit() and from an
+  // XPCOM shutdown notification that nsBaseAppShell has registered to
+  // receive.  So we need to ensure that multiple calls won't break anything.
+  // But we should also complain about it (since it isn't quite kosher).
+  if (mTerminated) {
+    NS_WARNING("nsAppShell::Exit() called redundantly");
+    return NS_OK;
+  }
+
+  mTerminated = true;
+
+#if !defined(RELEASE_OR_BETA) || defined(DEBUG)
+  nsSandboxViolationSink::Stop();
+#endif
+
+  // Quoting from Apple's doc on the [NSApplication stop:] method (from their
+  // doc on the NSApplication class):  "If this method is invoked during a
+  // modal event loop, it will break that loop but not the main event loop."
+  // nsAppShell::Exit() shouldn't be called from a modal event loop.  So if
+  // it is we complain about it (to users of debug builds) and call [NSApp
+  // stop:] one extra time.  (I'm not sure if modal event loops can be nested
+  // -- Apple's docs don't say one way or the other.  But the return value
+  // of [NSApp _isRunningModal] doesn't change immediately after a call to
+  // [NSApp stop:], so we have to assume that one extra call to [NSApp stop:]
+  // will do the job.)
+  BOOL cocoaModal = [NSApp _isRunningModal];
+  NS_ASSERTION(!cocoaModal,
+               "Don't call nsAppShell::Exit() from a modal event loop!");
+  if (cocoaModal)
+    [NSApp stop:nullptr];
+  [NSApp stop:nullptr];
+
+  // A call to Exit() just after a call to ScheduleNativeEventCallback()
+  // prevents the (normally) matching call to ProcessGeckoEvents() from
+  // happening.  If we've been called from ProcessGeckoEvents() (as usually
+  // happens), we take care of it there.  But if we have an unbalanced call
+  // to ScheduleNativeEventCallback() and ProcessGeckoEvents() isn't on the
+  // stack, we need to take care of the problem here.
+  if (!mNativeEventCallbackDepth && mNativeEventScheduledDepth) {
+    int32_t releaseCount = PR_ATOMIC_SET(&mNativeEventScheduledDepth, 0);
+    while (releaseCount-- > 0)
+      NS_RELEASE_THIS();
+  }
+
+  return nsBaseAppShell::Exit();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// OnProcessNextEvent
+//
+// This nsIThreadObserver method is called prior to processing an event.
+// Set up an autorelease pool that will service any autoreleased Cocoa
+// objects during this event.  This includes native events processed by
+// ProcessNextNativeEvent.  The autorelease pool will be popped by
+// AfterProcessNextEvent, it is important for these two methods to be
+// tightly coupled.
+//
+// public
+NS_IMETHODIMP
+nsAppShell::OnProcessNextEvent(nsIThreadInternal *aThread, bool aMayWait)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NS_ASSERTION(mAutoreleasePools,
+               "No stack on which to store autorelease pool");
+
+  NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
+  ::CFArrayAppendValue(mAutoreleasePools, pool);
+
+  return nsBaseAppShell::OnProcessNextEvent(aThread, aMayWait);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// AfterProcessNextEvent
+//
+// This nsIThreadObserver method is called after event processing is complete.
+// The Cocoa implementation cleans up the autorelease pool create by the
+// previous OnProcessNextEvent call.
+//
+// public
+NS_IMETHODIMP
+nsAppShell::AfterProcessNextEvent(nsIThreadInternal *aThread,
+                                  bool aEventWasProcessed)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  CFIndex count = ::CFArrayGetCount(mAutoreleasePools);
+
+  NS_ASSERTION(mAutoreleasePools && count,
+               "Processed an event, but there's no autorelease pool?");
+
+  const NSAutoreleasePool* pool = static_cast<const NSAutoreleasePool*>
+    (::CFArrayGetValueAtIndex(mAutoreleasePools, count - 1));
+  ::CFArrayRemoveValueAtIndex(mAutoreleasePools, count - 1);
+  [pool release];
+
+  return nsBaseAppShell::AfterProcessNextEvent(aThread, aEventWasProcessed);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+
+// AppShellDelegate implementation
+
+
+@implementation AppShellDelegate
+// initWithAppShell:
+//
+// Constructs the AppShellDelegate object
+- (id)initWithAppShell:(nsAppShell*)aAppShell
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if ((self = [self init])) {
+    mAppShell = aAppShell;
+
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(applicationWillTerminate:)
+                                                 name:NSApplicationWillTerminateNotification
+                                               object:NSApp];
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(applicationDidBecomeActive:)
+                                                 name:NSApplicationDidBecomeActiveNotification
+                                               object:NSApp];
+    [[NSDistributedNotificationCenter defaultCenter] addObserver:self
+                                                        selector:@selector(beginMenuTracking:)
+                                                            name:@"com.apple.HIToolbox.beginMenuTrackingNotification"
+                                                          object:nil];
+  }
+
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  [[NSDistributedNotificationCenter defaultCenter] removeObserver:self];
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// applicationWillTerminate:
+//
+// Notify the nsAppShell that native event processing should be discontinued.
+- (void)applicationWillTerminate:(NSNotification*)aNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  mAppShell->WillTerminate();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// applicationDidBecomeActive
+//
+// Make sure TextInputHandler::sLastModifierState is updated when we become
+// active (since we won't have received [ChildView flagsChanged:] messages
+// while inactive).
+- (void)applicationDidBecomeActive:(NSNotification*)aNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // [NSEvent modifierFlags] is valid on every kind of event, so we don't need
+  // to worry about getting an NSInternalInconsistencyException here.
+  NSEvent* currentEvent = [NSApp currentEvent];
+  if (currentEvent) {
+    TextInputHandler::sLastModifierState =
+      [currentEvent modifierFlags] & NSDeviceIndependentModifierFlagsMask;
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// beginMenuTracking
+//
+// Roll up our context menu (if any) when some other app (or the OS) opens
+// any sort of menu.  But make sure we don't do this for notifications we
+// send ourselves (whose 'sender' will be @"org.mozilla.gecko.PopupWindow").
+- (void)beginMenuTracking:(NSNotification*)aNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NSString *sender = [aNotification object];
+  if (!sender || ![sender isEqualToString:@"org.mozilla.gecko.PopupWindow"]) {
+    nsIRollupListener* rollupListener = nsBaseWidget::GetActiveRollupListener();
+    nsCOMPtr<nsIWidget> rollupWidget = rollupListener->GetRollupWidget();
+    if (rollupWidget)
+      rollupListener->Rollup(0, true, nullptr, nullptr);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@end
+
+// We hook terminate: in order to make OS-initiated termination work nicely
+// with Gecko's shutdown sequence.  (Two ways to trigger OS-initiated
+// termination:  1) Quit from the Dock menu; 2) Log out from (or shut down)
+// your computer while the browser is active.)
+@interface NSApplication (MethodSwizzling)
+- (void)nsAppShell_NSApplication_terminate:(id)sender;
+@end
+
+@implementation NSApplication (MethodSwizzling)
+
+// Called by the OS after [MacApplicationDelegate applicationShouldTerminate:]
+// has returned NSTerminateNow.  This method "subclasses" and replaces the
+// OS's original implementation.  The only thing the orginal method does which
+// we need is that it posts NSApplicationWillTerminateNotification.  Everything
+// else is unneeded (because it's handled elsewhere), or actively interferes
+// with Gecko's shutdown sequence.  For example the original terminate: method
+// causes the app to exit() inside [NSApp run] (called from nsAppShell::Run()
+// above), which means that nothing runs after the call to nsAppStartup::Run()
+// in XRE_Main(), which in particular means that ScopedXPCOMStartup's destructor
+// and NS_ShutdownXPCOM() never get called.
+- (void)nsAppShell_NSApplication_terminate:(id)sender
+{
+  [[NSNotificationCenter defaultCenter] postNotificationName:NSApplicationWillTerminateNotification
+                                                      object:NSApp];
+}
+
+@end
diff --git a/widget/cocoa/nsBidiKeyboard.h b/widget/cocoa/nsBidiKeyboard.h
new file mode 100644
index 0000000000..e7e7ac8722
--- /dev/null
+++ b/widget/cocoa/nsBidiKeyboard.h
@@ -0,0 +1,24 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsBidiKeyboard_h_
+#define nsBidiKeyboard_h_
+
+#include "nsIBidiKeyboard.h"
+
+class nsBidiKeyboard : public nsIBidiKeyboard
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIBIDIKEYBOARD
+
+  nsBidiKeyboard();
+
+protected:
+  virtual ~nsBidiKeyboard();
+};
+
+#endif // nsBidiKeyboard_h_
diff --git a/widget/cocoa/nsBidiKeyboard.mm b/widget/cocoa/nsBidiKeyboard.mm
new file mode 100644
index 0000000000..e0fc86aeb7
--- /dev/null
+++ b/widget/cocoa/nsBidiKeyboard.mm
@@ -0,0 +1,42 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsBidiKeyboard.h"
+#include "nsCocoaUtils.h"
+#include "TextInputHandler.h"
+
+// This must be the last include:
+#include "nsObjCExceptions.h"
+
+using namespace mozilla::widget;
+
+NS_IMPL_ISUPPORTS(nsBidiKeyboard, nsIBidiKeyboard)
+
+nsBidiKeyboard::nsBidiKeyboard() : nsIBidiKeyboard()
+{
+  Reset();
+}
+
+nsBidiKeyboard::~nsBidiKeyboard()
+{
+}
+
+NS_IMETHODIMP nsBidiKeyboard::Reset()
+{
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsBidiKeyboard::IsLangRTL(bool *aIsRTL)
+{
+  *aIsRTL = TISInputSourceWrapper::CurrentInputSource().IsForRTLLanguage();
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsBidiKeyboard::GetHaveBidiKeyboards(bool* aResult)
+{
+  // not implemented yet
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
diff --git a/widget/cocoa/nsChangeObserver.h b/widget/cocoa/nsChangeObserver.h
new file mode 100644
index 0000000000..1b9a001735
--- /dev/null
+++ b/widget/cocoa/nsChangeObserver.h
@@ -0,0 +1,44 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsChangeObserver_h_
+#define nsChangeObserver_h_
+
+class nsIContent;
+class nsIDocument;
+class nsIAtom;
+
+#define NS_DECL_CHANGEOBSERVER \
+void ObserveAttributeChanged(nsIDocument *aDocument, nsIContent *aContent, nsIAtom *aAttribute) override; \
+void ObserveContentRemoved(nsIDocument *aDocument, nsIContent *aChild, int32_t aIndexInContainer) override; \
+void ObserveContentInserted(nsIDocument *aDocument, nsIContent* aContainer, nsIContent *aChild) override;
+
+// Something that wants to be alerted to changes in attributes or changes in
+// its corresponding content object.
+//
+// This interface is used by our menu code so we only have to have one
+// nsIDocumentObserver.
+//
+// Any class that implements this interface must take care to unregister itself
+// on deletion.
+class nsChangeObserver
+{
+public:
+  // XXX use dom::Element
+  virtual void ObserveAttributeChanged(nsIDocument* aDocument,
+                                       nsIContent* aContent,
+                                       nsIAtom* aAttribute)=0;
+
+  virtual void ObserveContentRemoved(nsIDocument* aDocument,
+                                     nsIContent* aChild, 
+                                     int32_t aIndexInContainer)=0;
+
+  virtual void ObserveContentInserted(nsIDocument* aDocument,
+                                      nsIContent* aContainer,
+                                      nsIContent* aChild)=0;
+};
+
+#endif // nsChangeObserver_h_
diff --git a/widget/cocoa/nsChildView.h b/widget/cocoa/nsChildView.h
new file mode 100644
index 0000000000..2817c8d415
--- /dev/null
+++ b/widget/cocoa/nsChildView.h
@@ -0,0 +1,666 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsChildView_h_
+#define nsChildView_h_
+
+// formal protocols
+#include "mozView.h"
+#ifdef ACCESSIBILITY
+#include "mozilla/a11y/Accessible.h"
+#include "mozAccessibleProtocol.h"
+#endif
+
+#include "nsISupports.h"
+#include "nsBaseWidget.h"
+#include "nsWeakPtr.h"
+#include "TextInputHandler.h"
+#include "nsCocoaUtils.h"
+#include "gfxQuartzSurface.h"
+#include "GLContextTypes.h"
+#include "mozilla/Mutex.h"
+#include "nsRegion.h"
+#include "mozilla/MouseEvents.h"
+#include "mozilla/UniquePtr.h"
+
+#include "nsString.h"
+#include "nsIDragService.h"
+#include "ViewRegion.h"
+
+#import <Carbon/Carbon.h>
+#import <Cocoa/Cocoa.h>
+#import <AppKit/NSOpenGL.h>
+
+class nsChildView;
+class nsCocoaWindow;
+
+namespace {
+class GLPresenter;
+} // namespace
+
+namespace mozilla {
+class InputData;
+class PanGestureInput;
+class SwipeTracker;
+struct SwipeEventQueue;
+class VibrancyManager;
+namespace layers {
+class GLManager;
+class IAPZCTreeManager;
+} // namespace layers
+namespace widget {
+class RectTextureImage;
+class WidgetRenderingContext;
+} // namespace widget
+} // namespace mozilla
+
+@class PixelHostingView;
+
+@interface NSEvent (Undocumented)
+
+// Return Cocoa event's corresponding Carbon event.  Not initialized (on
+// synthetic events) until the OS actually "sends" the event.  This method
+// has been present in the same form since at least OS X 10.2.8.
+- (EventRef)_eventRef;
+
+@end
+
+@interface NSView (Undocumented)
+
+// Draws the title string of a window.
+// Present on NSThemeFrame since at least 10.6.
+// _drawTitleBar is somewhat complex, and has changed over the years
+// since OS X 10.6.  But in that time it's never done anything that
+// would break when called outside of -[NSView drawRect:] (which we
+// sometimes do), or whose output can't be redirected to a
+// CGContextRef object (which we also sometimes do).  This is likely
+// to remain true for the indefinite future.  However we should
+// check _drawTitleBar in each new major version of OS X.  For more
+// information see bug 877767.
+- (void)_drawTitleBar:(NSRect)aRect;
+
+// Returns an NSRect that is the bounding box for all an NSView's dirty
+// rectangles (ones that need to be redrawn).  The full list of dirty
+// rectangles can be obtained by calling -[NSView _dirtyRegion] and then
+// calling -[NSRegion getRects:count:] on what it returns.  Both these
+// methods have been present in the same form since at least OS X 10.5.
+// Unlike -[NSView getRectsBeingDrawn:count:], these methods can be called
+// outside a call to -[NSView drawRect:].
+- (NSRect)_dirtyRect;
+
+// Undocumented method of one or more of NSFrameView's subclasses.  Called
+// when one or more of the titlebar buttons needs to be repositioned, to
+// disappear, or to reappear (say if the window's style changes).  If
+// 'redisplay' is true, the entire titlebar (the window's top 22 pixels) is
+// marked as needing redisplay.  This method has been present in the same
+// format since at least OS X 10.5.
+- (void)_tileTitlebarAndRedisplay:(BOOL)redisplay;
+
+// The following undocumented methods are used to work around bug 1069658,
+// which is an Apple bug or design flaw that effects Yosemite.  None of them
+// were present prior to Yosemite (OS X 10.10).
+- (NSView *)titlebarView; // Method of NSThemeFrame
+- (NSView *)titlebarContainerView; // Method of NSThemeFrame
+- (BOOL)transparent; // Method of NSTitlebarView and NSTitlebarContainerView
+- (void)setTransparent:(BOOL)transparent; // Method of NSTitlebarView and
+                                          // NSTitlebarContainerView
+
+@end
+
+@interface ChildView : NSView<
+#ifdef ACCESSIBILITY
+                              mozAccessible,
+#endif
+                              mozView, NSTextInputClient>
+{
+@private
+  // the nsChildView that created the view. It retains this NSView, so
+  // the link back to it must be weak.
+  nsChildView* mGeckoChild;
+
+  // Text input handler for mGeckoChild and us.  Note that this is a weak
+  // reference.  Ideally, this should be a strong reference but a ChildView
+  // object can live longer than the mGeckoChild that owns it.  And if
+  // mTextInputHandler were a strong reference, this would make it difficult
+  // for Gecko's leak detector to detect leaked TextInputHandler objects.
+  // This is initialized by [mozView installTextInputHandler:aHandler] and
+  // cleared by [mozView uninstallTextInputHandler].
+  mozilla::widget::TextInputHandler* mTextInputHandler;  // [WEAK]
+
+  // when mouseDown: is called, we store its event here (strong)
+  NSEvent* mLastMouseDownEvent;
+
+  // Needed for IME support in e10s mode.  Strong.
+  NSEvent* mLastKeyDownEvent;
+
+  // Whether the last mouse down event was blocked from Gecko.
+  BOOL mBlockedLastMouseDown;
+
+  // when acceptsFirstMouse: is called, we store the event here (strong)
+  NSEvent* mClickThroughMouseDownEvent;
+
+  // WheelStart/Stop events should always come in pairs. This BOOL records the
+  // last received event so that, when we receive one of the events, we make sure
+  // to send its pair event first, in case we didn't yet for any reason.
+  BOOL mExpectingWheelStop;
+
+  // Set to YES when our GL surface has been updated and we need to call
+  // updateGLContext before we composite.
+  BOOL mNeedsGLUpdate;
+
+  // Holds our drag service across multiple drag calls. The reference to the
+  // service is obtained when the mouse enters the view and is released when
+  // the mouse exits or there is a drop. This prevents us from having to
+  // re-establish the connection to the service manager many times per second
+  // when handling |draggingUpdated:| messages.
+  nsIDragService* mDragService;
+
+  NSOpenGLContext *mGLContext;
+
+  // Simple gestures support
+  //
+  // mGestureState is used to detect when Cocoa has called both
+  // magnifyWithEvent and rotateWithEvent within the same
+  // beginGestureWithEvent and endGestureWithEvent sequence. We
+  // discard the spurious gesture event so as not to confuse Gecko.
+  //
+  // mCumulativeMagnification keeps track of the total amount of
+  // magnification peformed during a magnify gesture so that we can
+  // send that value with the final MozMagnifyGesture event.
+  //
+  // mCumulativeRotation keeps track of the total amount of rotation
+  // performed during a rotate gesture so we can send that value with
+  // the final MozRotateGesture event.
+  enum {
+    eGestureState_None,
+    eGestureState_StartGesture,
+    eGestureState_MagnifyGesture,
+    eGestureState_RotateGesture
+  } mGestureState;
+  float mCumulativeMagnification;
+  float mCumulativeRotation;
+
+#ifdef __LP64__
+  // Support for fluid swipe tracking.
+  BOOL* mCancelSwipeAnimation;
+#endif
+
+  // Whether this uses off-main-thread compositing.
+  BOOL mUsingOMTCompositor;
+
+  // The mask image that's used when painting into the titlebar using basic
+  // CGContext painting (i.e. non-accelerated).
+  CGImageRef mTopLeftCornerMask;
+
+  // Subviews of self, which act as container views for vibrancy views and
+  // non-draggable views.
+  NSView* mVibrancyViewsContainer;      // [STRONG]
+  NSView* mNonDraggableViewsContainer;  // [STRONG]
+
+  // The view that does our drawing. This is a subview of self so that it can
+  // be ordered on top of mVibrancyViewsContainer.
+  PixelHostingView* mPixelHostingView;
+}
+
+// class initialization
++ (void)initialize;
+
++ (void)registerViewForDraggedTypes:(NSView*)aView;
+
+// these are sent to the first responder when the window key status changes
+- (void)viewsWindowDidBecomeKey;
+- (void)viewsWindowDidResignKey;
+
+// Stop NSView hierarchy being changed during [ChildView drawRect:]
+- (void)delayedTearDown;
+
+- (void)sendFocusEvent:(mozilla::EventMessage)eventMessage;
+
+- (void)handleMouseMoved:(NSEvent*)aEvent;
+
+- (void)sendMouseEnterOrExitEvent:(NSEvent*)aEvent
+                            enter:(BOOL)aEnter
+                         exitFrom:(mozilla::WidgetMouseEvent::ExitFrom)aExitFrom;
+
+- (void)updateGLContext;
+- (void)_surfaceNeedsUpdate:(NSNotification*)notification;
+
+- (bool)preRender:(NSOpenGLContext *)aGLContext;
+- (void)postRender:(NSOpenGLContext *)aGLContext;
+
+- (NSView*)vibrancyViewsContainer;
+- (NSView*)nonDraggableViewsContainer;
+- (NSView*)pixelHostingView;
+
+- (BOOL)isCoveringTitlebar;
+
+- (void)viewWillStartLiveResize;
+- (void)viewDidEndLiveResize;
+
+- (NSColor*)vibrancyFillColorForThemeGeometryType:(nsITheme::ThemeGeometryType)aThemeGeometryType;
+- (NSColor*)vibrancyFontSmoothingBackgroundColorForThemeGeometryType:(nsITheme::ThemeGeometryType)aThemeGeometryType;
+
+// Simple gestures support
+//
+// XXX - The swipeWithEvent, beginGestureWithEvent, magnifyWithEvent,
+// rotateWithEvent, and endGestureWithEvent methods are part of a
+// PRIVATE interface exported by nsResponder and reverse-engineering
+// was necessary to obtain the methods' prototypes. Thus, Apple may
+// change the interface in the future without notice.
+//
+// The prototypes were obtained from the following link:
+// http://cocoadex.com/2008/02/nsevent-modifications-swipe-ro.html
+- (void)swipeWithEvent:(NSEvent *)anEvent;
+- (void)beginGestureWithEvent:(NSEvent *)anEvent;
+- (void)magnifyWithEvent:(NSEvent *)anEvent;
+- (void)smartMagnifyWithEvent:(NSEvent *)anEvent;
+- (void)rotateWithEvent:(NSEvent *)anEvent;
+- (void)endGestureWithEvent:(NSEvent *)anEvent;
+
+- (void)scrollWheel:(NSEvent *)anEvent;
+
+- (void)setUsingOMTCompositor:(BOOL)aUseOMTC;
+
+- (NSEvent*)lastKeyDownEvent;
+@end
+
+class ChildViewMouseTracker {
+
+public:
+
+  static void MouseMoved(NSEvent* aEvent);
+  static void MouseScrolled(NSEvent* aEvent);
+  static void OnDestroyView(ChildView* aView);
+  static void OnDestroyWindow(NSWindow* aWindow);
+  static BOOL WindowAcceptsEvent(NSWindow* aWindow, NSEvent* aEvent,
+                                 ChildView* aView, BOOL isClickThrough = NO);
+  static void MouseExitedWindow(NSEvent* aEvent);
+  static void MouseEnteredWindow(NSEvent* aEvent);
+  static void ReEvaluateMouseEnterState(NSEvent* aEvent = nil, ChildView* aOldView = nil);
+  static void ResendLastMouseMoveEvent();
+  static ChildView* ViewForEvent(NSEvent* aEvent);
+
+  static ChildView* sLastMouseEventView;
+  static NSEvent* sLastMouseMoveEvent;
+  static NSWindow* sWindowUnderMouse;
+  static NSPoint sLastScrollEventScreenLocation;
+};
+
+//-------------------------------------------------------------------------
+//
+// nsChildView
+//
+//-------------------------------------------------------------------------
+
+class nsChildView : public nsBaseWidget
+{
+private:
+  typedef nsBaseWidget Inherited;
+  typedef mozilla::layers::IAPZCTreeManager IAPZCTreeManager;
+
+public:
+  nsChildView();
+
+  // nsIWidget interface
+  virtual MOZ_MUST_USE nsresult Create(nsIWidget* aParent,
+                                       nsNativeWidget aNativeParent,
+                                       const LayoutDeviceIntRect& aRect,
+                                       nsWidgetInitData* aInitData = nullptr)
+                                       override;
+
+  virtual void            Destroy() override;
+
+  NS_IMETHOD              Show(bool aState) override;
+  virtual bool            IsVisible() const override;
+
+  NS_IMETHOD              SetParent(nsIWidget* aNewParent) override;
+  virtual nsIWidget*      GetParent(void) override;
+  virtual float           GetDPI() override;
+
+  NS_IMETHOD              Move(double aX, double aY) override;
+  NS_IMETHOD              Resize(double aWidth, double aHeight, bool aRepaint) override;
+  NS_IMETHOD              Resize(double aX, double aY,
+                                 double aWidth, double aHeight, bool aRepaint) override;
+
+  NS_IMETHOD              Enable(bool aState) override;
+  virtual bool            IsEnabled() const override;
+  NS_IMETHOD              SetFocus(bool aRaise) override;
+  virtual LayoutDeviceIntRect GetBounds() override;
+  virtual LayoutDeviceIntRect GetClientBounds() override;
+  virtual LayoutDeviceIntRect GetScreenBounds() override;
+
+  // Returns the "backing scale factor" of the view's window, which is the
+  // ratio of pixels in the window's backing store to Cocoa points. Prior to
+  // HiDPI support in OS X 10.7, this was always 1.0, but in HiDPI mode it
+  // will be 2.0 (and might potentially other values as screen resolutions
+  // evolve). This gives the relationship between what Gecko calls "device
+  // pixels" and the Cocoa "points" coordinate system.
+  CGFloat                 BackingScaleFactor() const;
+
+  mozilla::DesktopToLayoutDeviceScale GetDesktopToDeviceScale() final {
+    return mozilla::DesktopToLayoutDeviceScale(BackingScaleFactor());
+  }
+
+  // Call if the window's backing scale factor changes - i.e., it is moved
+  // between HiDPI and non-HiDPI screens
+  void                    BackingScaleFactorChanged();
+
+  virtual double          GetDefaultScaleInternal() override;
+
+  virtual int32_t         RoundsWidgetCoordinatesTo() override;
+
+  NS_IMETHOD              Invalidate(const LayoutDeviceIntRect &aRect) override;
+
+  virtual void*           GetNativeData(uint32_t aDataType) override;
+  virtual nsresult        ConfigureChildren(const nsTArray<Configuration>& aConfigurations) override;
+  virtual LayoutDeviceIntPoint WidgetToScreenOffset() override;
+  virtual bool            ShowsResizeIndicator(LayoutDeviceIntRect* aResizerRect) override;
+
+  static  bool            ConvertStatus(nsEventStatus aStatus)
+                          { return aStatus == nsEventStatus_eConsumeNoDefault; }
+  NS_IMETHOD              DispatchEvent(mozilla::WidgetGUIEvent* aEvent,
+                                        nsEventStatus& aStatus) override;
+
+  virtual bool            WidgetTypeSupportsAcceleration() override;
+  virtual bool            ShouldUseOffMainThreadCompositing() override;
+
+  NS_IMETHOD        SetCursor(nsCursor aCursor) override;
+  NS_IMETHOD        SetCursor(imgIContainer* aCursor, uint32_t aHotspotX, uint32_t aHotspotY) override;
+
+  NS_IMETHOD        SetTitle(const nsAString& title) override;
+
+  NS_IMETHOD        GetAttention(int32_t aCycleCount) override;
+
+  virtual bool HasPendingInputEvent() override;
+
+  NS_IMETHOD        ActivateNativeMenuItemAt(const nsAString& indexString) override;
+  NS_IMETHOD        ForceUpdateNativeMenuAt(const nsAString& indexString) override;
+  NS_IMETHOD        GetSelectionAsPlaintext(nsAString& aResult) override;
+
+  NS_IMETHOD_(void) SetInputContext(const InputContext& aContext,
+                                    const InputContextAction& aAction) override;
+  NS_IMETHOD_(InputContext) GetInputContext() override;
+  NS_IMETHOD_(TextEventDispatcherListener*)
+    GetNativeTextEventDispatcherListener() override;
+  NS_IMETHOD        AttachNativeKeyEvent(mozilla::WidgetKeyboardEvent& aEvent) override;
+  NS_IMETHOD_(bool) ExecuteNativeKeyBinding(
+                      NativeKeyBindingsType aType,
+                      const mozilla::WidgetKeyboardEvent& aEvent,
+                      DoCommandCallback aCallback,
+                      void* aCallbackData) override;
+  bool ExecuteNativeKeyBindingRemapped(
+                      NativeKeyBindingsType aType,
+                      const mozilla::WidgetKeyboardEvent& aEvent,
+                      DoCommandCallback aCallback,
+                      void* aCallbackData,
+                      uint32_t aGeckoKeyCode,
+                      uint32_t aCocoaKeyCode);
+  virtual nsIMEUpdatePreference GetIMEUpdatePreference() override;
+
+  virtual nsTransparencyMode GetTransparencyMode() override;
+  virtual void                SetTransparencyMode(nsTransparencyMode aMode) override;
+
+  virtual nsresult SynthesizeNativeKeyEvent(int32_t aNativeKeyboardLayout,
+                                            int32_t aNativeKeyCode,
+                                            uint32_t aModifierFlags,
+                                            const nsAString& aCharacters,
+                                            const nsAString& aUnmodifiedCharacters,
+                                            nsIObserver* aObserver) override;
+
+  virtual nsresult SynthesizeNativeMouseEvent(LayoutDeviceIntPoint aPoint,
+                                              uint32_t aNativeMessage,
+                                              uint32_t aModifierFlags,
+                                              nsIObserver* aObserver) override;
+
+  virtual nsresult SynthesizeNativeMouseMove(LayoutDeviceIntPoint aPoint,
+                                             nsIObserver* aObserver) override
+  { return SynthesizeNativeMouseEvent(aPoint, NSMouseMoved, 0, aObserver); }
+  virtual nsresult SynthesizeNativeMouseScrollEvent(LayoutDeviceIntPoint aPoint,
+                                                    uint32_t aNativeMessage,
+                                                    double aDeltaX,
+                                                    double aDeltaY,
+                                                    double aDeltaZ,
+                                                    uint32_t aModifierFlags,
+                                                    uint32_t aAdditionalFlags,
+                                                    nsIObserver* aObserver) override;
+  virtual nsresult SynthesizeNativeTouchPoint(uint32_t aPointerId,
+                                              TouchPointerState aPointerState,
+                                              LayoutDeviceIntPoint aPoint,
+                                              double aPointerPressure,
+                                              uint32_t aPointerOrientation,
+                                              nsIObserver* aObserver) override;
+
+  // Mac specific methods
+
+  virtual bool      DispatchWindowEvent(mozilla::WidgetGUIEvent& event);
+
+  void WillPaintWindow();
+  bool PaintWindow(LayoutDeviceIntRegion aRegion);
+  bool PaintWindowInContext(CGContextRef aContext, const LayoutDeviceIntRegion& aRegion,
+                            mozilla::gfx::IntSize aSurfaceSize);
+
+#ifdef ACCESSIBILITY
+  already_AddRefed<mozilla::a11y::Accessible> GetDocumentAccessible();
+#endif
+
+  virtual void CreateCompositor() override;
+  virtual void PrepareWindowEffects() override;
+  virtual void CleanupWindowEffects() override;
+  virtual bool PreRender(mozilla::widget::WidgetRenderingContext* aContext) override;
+  virtual void PostRender(mozilla::widget::WidgetRenderingContext* aContext) override;
+  virtual void DrawWindowOverlay(mozilla::widget::WidgetRenderingContext* aManager,
+                                 LayoutDeviceIntRect aRect) override;
+
+  virtual void UpdateThemeGeometries(const nsTArray<ThemeGeometry>& aThemeGeometries) override;
+
+  virtual void UpdateWindowDraggingRegion(const LayoutDeviceIntRegion& aRegion) override;
+  LayoutDeviceIntRegion GetNonDraggableRegion() { return mNonDraggableRegion.Region(); }
+
+  virtual void ReportSwipeStarted(uint64_t aInputBlockId, bool aStartSwipe) override;
+
+  virtual void LookUpDictionary(
+                 const nsAString& aText,
+                 const nsTArray<mozilla::FontRange>& aFontRangeArray,
+                 const bool aIsVertical,
+                 const LayoutDeviceIntPoint& aPoint) override;
+
+  void              ResetParent();
+
+  static bool DoHasPendingInputEvent();
+  static uint32_t GetCurrentInputEventCount();
+  static void UpdateCurrentInputEventCount();
+
+  NSView<mozView>* GetEditorView();
+
+  nsCocoaWindow*    GetXULWindowWidget();
+
+  virtual void      ReparentNativeWidget(nsIWidget* aNewParent) override;
+
+  mozilla::widget::TextInputHandler* GetTextInputHandler()
+  {
+    return mTextInputHandler;
+  }
+
+  void              ClearVibrantAreas();
+  NSColor*          VibrancyFillColorForThemeGeometryType(nsITheme::ThemeGeometryType aThemeGeometryType);
+  NSColor*          VibrancyFontSmoothingBackgroundColorForThemeGeometryType(nsITheme::ThemeGeometryType aThemeGeometryType);
+
+  // unit conversion convenience functions
+  int32_t           CocoaPointsToDevPixels(CGFloat aPts) const {
+    return nsCocoaUtils::CocoaPointsToDevPixels(aPts, BackingScaleFactor());
+  }
+  LayoutDeviceIntPoint CocoaPointsToDevPixels(const NSPoint& aPt) const {
+    return nsCocoaUtils::CocoaPointsToDevPixels(aPt, BackingScaleFactor());
+  }
+  LayoutDeviceIntPoint CocoaPointsToDevPixelsRoundDown(const NSPoint& aPt) const {
+    return nsCocoaUtils::CocoaPointsToDevPixelsRoundDown(aPt, BackingScaleFactor());
+  }
+  LayoutDeviceIntRect CocoaPointsToDevPixels(const NSRect& aRect) const {
+    return nsCocoaUtils::CocoaPointsToDevPixels(aRect, BackingScaleFactor());
+  }
+  CGFloat           DevPixelsToCocoaPoints(int32_t aPixels) const {
+    return nsCocoaUtils::DevPixelsToCocoaPoints(aPixels, BackingScaleFactor());
+  }
+  NSRect            DevPixelsToCocoaPoints(const LayoutDeviceIntRect& aRect) const {
+    return nsCocoaUtils::DevPixelsToCocoaPoints(aRect, BackingScaleFactor());
+  }
+
+  already_AddRefed<mozilla::gfx::DrawTarget>
+    StartRemoteDrawingInRegion(LayoutDeviceIntRegion& aInvalidRegion,
+                               mozilla::layers::BufferMode* aBufferMode) override;
+  void EndRemoteDrawing() override;
+  void CleanupRemoteDrawing() override;
+  bool InitCompositor(mozilla::layers::Compositor* aCompositor) override;
+
+  NS_IMETHOD StartPluginIME(const mozilla::WidgetKeyboardEvent& aKeyboardEvent,
+                            int32_t aPanelX, int32_t aPanelY,
+                            nsString& aCommitted) override;
+
+  virtual void SetPluginFocused(bool& aFocused) override;
+
+  bool IsPluginFocused() { return mPluginFocused; }
+
+  virtual LayoutDeviceIntPoint GetClientOffset() override;
+
+  void DispatchAPZWheelInputEvent(mozilla::InputData& aEvent, bool aCanTriggerSwipe);
+
+  void SwipeFinished();
+
+protected:
+  virtual ~nsChildView();
+
+  void              ReportMoveEvent();
+  void              ReportSizeEvent();
+
+  void              TearDownView();
+
+  virtual already_AddRefed<nsIWidget>
+  AllocateChildPopupWidget() override
+  {
+    static NS_DEFINE_IID(kCPopUpCID, NS_POPUP_CID);
+    nsCOMPtr<nsIWidget> widget = do_CreateInstance(kCPopUpCID);
+    return widget.forget();
+  }
+
+  void ConfigureAPZCTreeManager() override;
+  void ConfigureAPZControllerThread() override;
+
+  void DoRemoteComposition(const LayoutDeviceIntRect& aRenderRect);
+
+  // Overlay drawing functions for OpenGL drawing
+  void DrawWindowOverlay(mozilla::layers::GLManager* aManager, LayoutDeviceIntRect aRect);
+  void MaybeDrawResizeIndicator(mozilla::layers::GLManager* aManager);
+  void MaybeDrawRoundedCorners(mozilla::layers::GLManager* aManager, const LayoutDeviceIntRect& aRect);
+  void MaybeDrawTitlebar(mozilla::layers::GLManager* aManager);
+
+  // Redraw the contents of mTitlebarCGContext on the main thread, as
+  // determined by mDirtyTitlebarRegion.
+  void UpdateTitlebarCGContext();
+
+  LayoutDeviceIntRect RectContainingTitlebarControls();
+  void UpdateVibrancy(const nsTArray<ThemeGeometry>& aThemeGeometries);
+  mozilla::VibrancyManager& EnsureVibrancyManager();
+
+  nsIWidget* GetWidgetForListenerEvents();
+
+  struct SwipeInfo {
+    bool wantsSwipe;
+    uint32_t allowedDirections;
+  };
+
+  SwipeInfo SendMayStartSwipe(const mozilla::PanGestureInput& aSwipeStartEvent);
+  void TrackScrollEventAsSwipe(const mozilla::PanGestureInput& aSwipeStartEvent,
+                               uint32_t aAllowedDirections);
+
+protected:
+
+  ChildView<mozView>* mView;  // my parallel cocoa view, [STRONG]
+  RefPtr<mozilla::widget::TextInputHandler> mTextInputHandler;
+  InputContext          mInputContext;
+
+  NSView<mozView>*      mParentView;
+  nsIWidget*            mParentWidget;
+
+#ifdef ACCESSIBILITY
+  // weak ref to this childview's associated mozAccessible for speed reasons
+  // (we get queried for it *a lot* but don't want to own it)
+  nsWeakPtr             mAccessible;
+#endif
+
+  // Protects the view from being teared down while a composition is in
+  // progress on the compositor thread.
+  mozilla::Mutex mViewTearDownLock;
+
+  mozilla::Mutex mEffectsLock;
+
+  // May be accessed from any thread, protected
+  // by mEffectsLock.
+  bool mShowsResizeIndicator;
+  LayoutDeviceIntRect mResizeIndicatorRect;
+  bool mHasRoundedBottomCorners;
+  int mDevPixelCornerRadius;
+  bool mIsCoveringTitlebar;
+  bool mIsFullscreen;
+  bool mIsOpaque;
+  LayoutDeviceIntRect mTitlebarRect;
+
+  // The area of mTitlebarCGContext that needs to be redrawn during the next
+  // transaction. Accessed from any thread, protected by mEffectsLock.
+  LayoutDeviceIntRegion mUpdatedTitlebarRegion;
+  CGContextRef mTitlebarCGContext;
+
+  // Compositor thread only
+  mozilla::UniquePtr<mozilla::widget::RectTextureImage> mResizerImage;
+  mozilla::UniquePtr<mozilla::widget::RectTextureImage> mCornerMaskImage;
+  mozilla::UniquePtr<mozilla::widget::RectTextureImage> mTitlebarImage;
+  mozilla::UniquePtr<mozilla::widget::RectTextureImage> mBasicCompositorImage;
+
+  // The area of mTitlebarCGContext that has changed and needs to be
+  // uploaded to to mTitlebarImage. Main thread only.
+  nsIntRegion           mDirtyTitlebarRegion;
+
+  mozilla::ViewRegion   mNonDraggableRegion;
+
+  // Cached value of [mView backingScaleFactor], to avoid sending two obj-c
+  // messages (respondsToSelector, backingScaleFactor) every time we need to
+  // use it.
+  // ** We'll need to reinitialize this if the backing resolution changes. **
+  mutable CGFloat       mBackingScaleFactor;
+
+  bool                  mVisible;
+  bool                  mDrawing;
+  bool                  mIsDispatchPaint; // Is a paint event being dispatched
+
+  bool mPluginFocused;
+
+  // Used in OMTC BasicLayers mode. Presents the BasicCompositor result
+  // surface to the screen using an OpenGL context.
+  mozilla::UniquePtr<GLPresenter> mGLPresenter;
+
+  mozilla::UniquePtr<mozilla::VibrancyManager> mVibrancyManager;
+  RefPtr<mozilla::SwipeTracker> mSwipeTracker;
+  mozilla::UniquePtr<mozilla::SwipeEventQueue> mSwipeEventQueue;
+
+  // Only used for drawRect-based painting in popups.
+  RefPtr<mozilla::gfx::DrawTarget> mBackingSurface;
+
+  // This flag is only used when APZ is off. It indicates that the current pan
+  // gesture was processed as a swipe. Sometimes the swipe animation can finish
+  // before momentum events of the pan gesture have stopped firing, so this
+  // flag tells us that we shouldn't allow the remaining events to cause
+  // scrolling. It is reset to false once a new gesture starts (as indicated by
+  // a PANGESTURE_(MAY)START event).
+  bool mCurrentPanGestureBelongsToSwipe;
+
+  static uint32_t sLastInputEventCount;
+
+  void ReleaseTitlebarCGContext();
+
+  // This is used by SynthesizeNativeTouchPoint to maintain state between
+  // multiple synthesized points
+  mozilla::UniquePtr<mozilla::MultiTouchInput> mSynthesizedTouchInput;
+};
+
+#endif // nsChildView_h_
diff --git a/widget/cocoa/nsChildView.mm b/widget/cocoa/nsChildView.mm
new file mode 100644
index 0000000000..868687fe16
--- /dev/null
+++ b/widget/cocoa/nsChildView.mm
@@ -0,0 +1,6151 @@
+/* -*- Mode: objc; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/ArrayUtils.h"
+
+#include "mozilla/Logging.h"
+
+#include <unistd.h>
+#include <math.h>
+
+#include "nsChildView.h"
+#include "nsCocoaWindow.h"
+
+#include "mozilla/MiscEvents.h"
+#include "mozilla/MouseEvents.h"
+#include "mozilla/TextEvents.h"
+#include "mozilla/TouchEvents.h"
+
+#include "nsArrayUtils.h"
+#include "nsObjCExceptions.h"
+#include "nsCOMPtr.h"
+#include "nsToolkit.h"
+#include "nsCRT.h"
+
+#include "nsFontMetrics.h"
+#include "nsIRollupListener.h"
+#include "nsViewManager.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIFile.h"
+#include "nsILocalFileMac.h"
+#include "nsGfxCIID.h"
+#include "nsIDOMSimpleGestureEvent.h"
+#include "nsThemeConstants.h"
+#include "nsIWidgetListener.h"
+#include "nsIPresShell.h"
+
+#include "nsDragService.h"
+#include "nsClipboard.h"
+#include "nsCursorManager.h"
+#include "nsWindowMap.h"
+#include "nsCocoaFeatures.h"
+#include "nsCocoaUtils.h"
+#include "nsMenuUtilsX.h"
+#include "nsMenuBarX.h"
+#include "NativeKeyBindings.h"
+#include "ComplexTextInputPanel.h"
+
+#include "gfxContext.h"
+#include "gfxQuartzSurface.h"
+#include "gfxUtils.h"
+#include "nsRegion.h"
+#include "Layers.h"
+#include "ClientLayerManager.h"
+#include "mozilla/layers/LayerManagerComposite.h"
+#include "GfxTexturesReporter.h"
+#include "GLTextureImage.h"
+#include "GLContextProvider.h"
+#include "GLContextCGL.h"
+#include "ScopedGLHelpers.h"
+#include "HeapCopyOfStackArray.h"
+#include "mozilla/layers/IAPZCTreeManager.h"
+#include "mozilla/layers/APZThreadUtils.h"
+#include "mozilla/layers/GLManager.h"
+#include "mozilla/layers/CompositorOGL.h"
+#include "mozilla/layers/CompositorBridgeParent.h"
+#include "mozilla/layers/BasicCompositor.h"
+#include "mozilla/layers/InputAPZContext.h"
+#include "mozilla/widget/CompositorWidget.h"
+#include "gfxUtils.h"
+#include "gfxPrefs.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/gfx/BorrowedContext.h"
+#include "mozilla/gfx/MacIOSurface.h"
+#ifdef ACCESSIBILITY
+#include "nsAccessibilityService.h"
+#include "mozilla/a11y/Platform.h"
+#endif
+
+#include "mozilla/Preferences.h"
+
+#include <dlfcn.h>
+
+#include <ApplicationServices/ApplicationServices.h>
+
+#include "GeckoProfiler.h"
+
+#include "nsIDOMWheelEvent.h"
+#include "mozilla/layers/ChromeProcessController.h"
+#include "nsLayoutUtils.h"
+#include "InputData.h"
+#include "RectTextureImage.h"
+#include "SwipeTracker.h"
+#include "VibrancyManager.h"
+#include "nsNativeThemeCocoa.h"
+#include "nsIDOMWindowUtils.h"
+#include "Units.h"
+#include "UnitTransforms.h"
+#include "mozilla/UniquePtrExtensions.h"
+
+using namespace mozilla;
+using namespace mozilla::layers;
+using namespace mozilla::gl;
+using namespace mozilla::widget;
+
+using mozilla::gfx::Matrix4x4;
+
+#undef DEBUG_UPDATE
+#undef INVALIDATE_DEBUGGING  // flash areas as they are invalidated
+
+// Don't put more than this many rects in the dirty region, just fluff
+// out to the bounding-box if there are more
+#define MAX_RECTS_IN_REGION 100
+
+PRLogModuleInfo* sCocoaLog = nullptr;
+
+extern "C" {
+  CG_EXTERN void CGContextResetCTM(CGContextRef);
+  CG_EXTERN void CGContextSetCTM(CGContextRef, CGAffineTransform);
+  CG_EXTERN void CGContextResetClip(CGContextRef);
+
+  typedef CFTypeRef CGSRegionObj;
+  CGError CGSNewRegionWithRect(const CGRect *rect, CGSRegionObj *outRegion);
+  CGError CGSNewRegionWithRectList(const CGRect *rects, int rectCount, CGSRegionObj *outRegion);
+}
+
+// defined in nsMenuBarX.mm
+extern NSMenu* sApplicationMenu; // Application menu shared by all menubars
+
+static bool gChildViewMethodsSwizzled = false;
+
+extern nsIArray *gDraggedTransferables;
+
+ChildView* ChildViewMouseTracker::sLastMouseEventView = nil;
+NSEvent* ChildViewMouseTracker::sLastMouseMoveEvent = nil;
+NSWindow* ChildViewMouseTracker::sWindowUnderMouse = nil;
+NSPoint ChildViewMouseTracker::sLastScrollEventScreenLocation = NSZeroPoint;
+
+#ifdef INVALIDATE_DEBUGGING
+static void blinkRect(Rect* r);
+static void blinkRgn(RgnHandle rgn);
+#endif
+
+bool gUserCancelledDrag = false;
+
+uint32_t nsChildView::sLastInputEventCount = 0;
+
+// The view that will do our drawing or host our NSOpenGLContext or Core Animation layer.
+@interface PixelHostingView : NSView {
+}
+@end
+
+@interface ChildView(Private)
+
+// sets up our view, attaching it to its owning gecko view
+- (id)initWithFrame:(NSRect)inFrame geckoChild:(nsChildView*)inChild;
+
+// set up a gecko mouse event based on a cocoa mouse event
+- (void) convertCocoaMouseWheelEvent:(NSEvent*)aMouseEvent
+                        toGeckoEvent:(WidgetWheelEvent*)outWheelEvent;
+- (void) convertCocoaMouseEvent:(NSEvent*)aMouseEvent
+                   toGeckoEvent:(WidgetInputEvent*)outGeckoEvent;
+
+- (NSMenu*)contextMenu;
+
+- (BOOL)isRectObscuredBySubview:(NSRect)inRect;
+
+- (LayoutDeviceIntRegion)nativeDirtyRegionWithBoundingRect:(NSRect)aRect;
+- (BOOL)isUsingOpenGL;
+- (void)drawUsingOpenGL;
+
+- (BOOL)hasRoundedBottomCorners;
+- (CGFloat)cornerRadius;
+- (void)clearCorners;
+
+-(void)setGLOpaque:(BOOL)aOpaque;
+
+// Overlay drawing functions for traditional CGContext drawing
+- (void)drawTitleString;
+- (void)drawTitlebarHighlight;
+- (void)maskTopCornersInContext:(CGContextRef)aContext;
+
+#if USE_CLICK_HOLD_CONTEXTMENU
+ // called on a timer two seconds after a mouse down to see if we should display
+ // a context menu (click-hold)
+- (void)clickHoldCallback:(id)inEvent;
+#endif
+
+#ifdef ACCESSIBILITY
+- (id<mozAccessible>)accessible;
+#endif
+
+- (LayoutDeviceIntPoint)convertWindowCoordinates:(NSPoint)aPoint;
+- (LayoutDeviceIntPoint)convertWindowCoordinatesRoundDown:(NSPoint)aPoint;
+
+- (BOOL)inactiveWindowAcceptsMouseEvent:(NSEvent*)aEvent;
+- (void)updateWindowDraggableState;
+
+- (bool)shouldConsiderStartingSwipeFromEvent:(NSEvent*)aEvent;
+
+@end
+
+@interface NSView(NSThemeFrameCornerRadius)
+- (float)roundedCornerRadius;
+@end
+
+@interface NSWindow(NSWindowShouldZoomOnDoubleClick)
++ (BOOL)_shouldZoomOnDoubleClick; // present on 10.7 and above
+@end
+
+// Starting with 10.7 the bottom corners of all windows are rounded.
+// Unfortunately, the standard rounding that OS X applies to OpenGL views
+// does not use anti-aliasing and looks very crude. Since we want a smooth,
+// anti-aliased curve, we'll draw it ourselves.
+// Additionally, we need to turn off the OS-supplied rounding because it
+// eats into our corner's curve. We do that by overriding an NSSurface method.
+@interface NSSurface @end
+
+@implementation NSSurface(DontCutOffCorners)
+- (CGSRegionObj)_createRoundedBottomRegionForRect:(CGRect)rect
+{
+  // Create a normal rect region without rounded bottom corners.
+  CGSRegionObj region;
+  CGSNewRegionWithRect(&rect, &region);
+  return region;
+}
+@end
+
+#pragma mark -
+
+// Flips a screen coordinate from a point in the cocoa coordinate system (bottom-left rect) to a point
+// that is a "flipped" cocoa coordinate system (starts in the top-left).
+static inline void
+FlipCocoaScreenCoordinate(NSPoint &inPoint)
+{
+  inPoint.y = nsCocoaUtils::FlippedScreenY(inPoint.y);
+}
+
+void EnsureLogInitialized()
+{
+  if (!sCocoaLog) {
+    sCocoaLog = PR_NewLogModule("nsCocoaWidgets");
+  }
+}
+
+namespace {
+
+// Used for OpenGL drawing from the compositor thread for OMTC BasicLayers.
+// We need to use OpenGL for this because there seems to be no other robust
+// way of drawing from a secondary thread without locking, which would cause
+// deadlocks in our setup. See bug 882523.
+class GLPresenter : public GLManager
+{
+public:
+  static mozilla::UniquePtr<GLPresenter> CreateForWindow(nsIWidget* aWindow)
+  {
+    // Contrary to CompositorOGL, we allow unaccelerated OpenGL contexts to be
+    // used. BasicCompositor only requires very basic GL functionality.
+    RefPtr<GLContext> context = gl::GLContextProvider::CreateForWindow(aWindow, false);
+    return context ? MakeUnique<GLPresenter>(context) : nullptr;
+  }
+
+  explicit GLPresenter(GLContext* aContext);
+  virtual ~GLPresenter();
+
+  virtual GLContext* gl() const override { return mGLContext; }
+  virtual ShaderProgramOGL* GetProgram(GLenum aTarget, gfx::SurfaceFormat aFormat) override
+  {
+    MOZ_ASSERT(aTarget == LOCAL_GL_TEXTURE_RECTANGLE_ARB);
+    MOZ_ASSERT(aFormat == gfx::SurfaceFormat::R8G8B8A8);
+    return mRGBARectProgram.get();
+  }
+  virtual const gfx::Matrix4x4& GetProjMatrix() const override
+  {
+    return mProjMatrix;
+  }
+  virtual void ActivateProgram(ShaderProgramOGL *aProg) override
+  {
+    mGLContext->fUseProgram(aProg->GetProgram());
+  }
+  virtual void BindAndDrawQuad(ShaderProgramOGL *aProg,
+                               const gfx::Rect& aLayerRect,
+                               const gfx::Rect& aTextureRect) override;
+
+  void BeginFrame(LayoutDeviceIntSize aRenderSize);
+  void EndFrame();
+
+  NSOpenGLContext* GetNSOpenGLContext()
+  {
+    return GLContextCGL::Cast(mGLContext)->GetNSOpenGLContext();
+  }
+
+protected:
+  RefPtr<mozilla::gl::GLContext> mGLContext;
+  mozilla::UniquePtr<mozilla::layers::ShaderProgramOGL> mRGBARectProgram;
+  gfx::Matrix4x4 mProjMatrix;
+  GLuint mQuadVBO;
+};
+
+} // unnamed namespace
+
+namespace mozilla {
+
+struct SwipeEventQueue {
+  SwipeEventQueue(uint32_t aAllowedDirections, uint64_t aInputBlockId)
+    : allowedDirections(aAllowedDirections)
+    , inputBlockId(aInputBlockId)
+  {}
+
+  nsTArray<PanGestureInput> queuedEvents;
+  uint32_t allowedDirections;
+  uint64_t inputBlockId;
+};
+
+} // namespace mozilla
+
+#pragma mark -
+
+nsChildView::nsChildView() : nsBaseWidget()
+, mView(nullptr)
+, mParentView(nullptr)
+, mParentWidget(nullptr)
+, mViewTearDownLock("ChildViewTearDown")
+, mEffectsLock("WidgetEffects")
+, mShowsResizeIndicator(false)
+, mHasRoundedBottomCorners(false)
+, mIsCoveringTitlebar(false)
+, mIsFullscreen(false)
+, mIsOpaque(false)
+, mTitlebarCGContext(nullptr)
+, mBackingScaleFactor(0.0)
+, mVisible(false)
+, mDrawing(false)
+, mIsDispatchPaint(false)
+{
+  EnsureLogInitialized();
+}
+
+nsChildView::~nsChildView()
+{
+  ReleaseTitlebarCGContext();
+
+  if (mSwipeTracker) {
+    mSwipeTracker->Destroy();
+    mSwipeTracker = nullptr;
+  }
+
+  // Notify the children that we're gone.  childView->ResetParent() can change
+  // our list of children while it's being iterated, so the way we iterate the
+  // list must allow for this.
+  for (nsIWidget* kid = mLastChild; kid;) {
+    nsChildView* childView = static_cast<nsChildView*>(kid);
+    kid = kid->GetPrevSibling();
+    childView->ResetParent();
+  }
+
+  NS_WARNING_ASSERTION(
+    mOnDestroyCalled,
+    "nsChildView object destroyed without calling Destroy()");
+
+  DestroyCompositor();
+
+  // An nsChildView object that was in use can be destroyed without Destroy()
+  // ever being called on it.  So we also need to do a quick, safe cleanup
+  // here (it's too late to just call Destroy(), which can cause crashes).
+  // It's particularly important to make sure widgetDestroyed is called on our
+  // mView -- this method NULLs mView's mGeckoChild, and NULL checks on
+  // mGeckoChild are used throughout the ChildView class to tell if it's safe
+  // to use a ChildView object.
+  [mView widgetDestroyed]; // Safe if mView is nil.
+  mParentWidget = nil;
+  TearDownView(); // Safe if called twice.
+}
+
+void
+nsChildView::ReleaseTitlebarCGContext()
+{
+  if (mTitlebarCGContext) {
+    CGContextRelease(mTitlebarCGContext);
+    mTitlebarCGContext = nullptr;
+  }
+}
+
+nsresult
+nsChildView::Create(nsIWidget* aParent,
+                    nsNativeWidget aNativeParent,
+                    const LayoutDeviceIntRect& aRect,
+                    nsWidgetInitData* aInitData)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // Because the hidden window is created outside of an event loop,
+  // we need to provide an autorelease pool to avoid leaking cocoa objects
+  // (see bug 559075).
+  nsAutoreleasePool localPool;
+
+  // See NSView (MethodSwizzling) below.
+  if (!gChildViewMethodsSwizzled) {
+    nsToolkit::SwizzleMethods([NSView class], @selector(mouseDownCanMoveWindow),
+                              @selector(nsChildView_NSView_mouseDownCanMoveWindow));
+    gChildViewMethodsSwizzled = true;
+  }
+
+  mBounds = aRect;
+
+  // Ensure that the toolkit is created.
+  nsToolkit::GetToolkit();
+
+  BaseCreate(aParent, aInitData);
+
+  // inherit things from the parent view and create our parallel
+  // NSView in the Cocoa display system
+  mParentView = nil;
+  if (aParent) {
+    // inherit the top-level window. NS_NATIVE_WIDGET is always a NSView
+    // regardless of if we're asking a window or a view (for compatibility
+    // with windows).
+    mParentView = (NSView<mozView>*)aParent->GetNativeData(NS_NATIVE_WIDGET);
+    mParentWidget = aParent;
+  } else {
+    // This is the normal case. When we're the root widget of the view hiararchy,
+    // aNativeParent will be the contentView of our window, since that's what
+    // nsCocoaWindow returns when asked for an NS_NATIVE_VIEW.
+    mParentView = reinterpret_cast<NSView<mozView>*>(aNativeParent);
+  }
+
+  // create our parallel NSView and hook it up to our parent. Recall
+  // that NS_NATIVE_WIDGET is the NSView.
+  CGFloat scaleFactor = nsCocoaUtils::GetBackingScaleFactor(mParentView);
+  NSRect r = nsCocoaUtils::DevPixelsToCocoaPoints(mBounds, scaleFactor);
+  mView = [[[[ChildView alloc] initWithFrame:r geckoChild:this] autorelease] retain];
+  
+  if (!mView) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // If this view was created in a Gecko view hierarchy, the initial state
+  // is hidden.  If the view is attached only to a native NSView but has
+  // no Gecko parent (as in embedding), the initial state is visible.
+  if (mParentWidget)
+    [mView setHidden:YES];
+  else
+    mVisible = true;
+
+  // Hook it up in the NSView hierarchy.
+  if (mParentView) {
+    [mParentView addSubview:mView];
+  }
+
+  // if this is a ChildView, make sure that our per-window data
+  // is set up
+  if ([mView isKindOfClass:[ChildView class]])
+    [[WindowDataMap sharedWindowDataMap] ensureDataForWindow:[mView window]];
+
+  NS_ASSERTION(!mTextInputHandler, "mTextInputHandler has already existed");
+  mTextInputHandler = new TextInputHandler(this, mView);
+
+  mPluginFocused = false;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+
+void nsChildView::TearDownView()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mView)
+    return;
+
+  NSWindow* win = [mView window];
+  NSResponder* responder = [win firstResponder];
+
+  // We're being unhooked from the view hierarchy, don't leave our view
+  // or a child view as the window first responder.
+  if (responder && [responder isKindOfClass:[NSView class]] &&
+      [(NSView*)responder isDescendantOf:mView]) {
+    [win makeFirstResponder:[mView superview]];
+  }
+
+  // If mView is win's contentView, win (mView's NSWindow) "owns" mView --
+  // win has retained mView, and will detach it from the view hierarchy and
+  // release it when necessary (when win is itself destroyed (in a call to
+  // [win dealloc])).  So all we need to do here is call [mView release] (to
+  // match the call to [mView retain] in nsChildView::StandardCreate()).
+  // Also calling [mView removeFromSuperviewWithoutNeedingDisplay] causes
+  // mView to be released again and dealloced, while remaining win's
+  // contentView.  So if we do that here, win will (for a short while) have
+  // an invalid contentView (for the consequences see bmo bugs 381087 and
+  // 374260).
+  if ([mView isEqual:[win contentView]]) {
+    [mView release];
+  } else {
+    // Stop NSView hierarchy being changed during [ChildView drawRect:]
+    [mView performSelectorOnMainThread:@selector(delayedTearDown) withObject:nil waitUntilDone:false];
+  }
+  mView = nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsCocoaWindow*
+nsChildView::GetXULWindowWidget()
+{
+  id windowDelegate = [[mView window] delegate];
+  if (windowDelegate && [windowDelegate isKindOfClass:[WindowDelegate class]]) {
+    return [(WindowDelegate *)windowDelegate geckoWidget];
+  }
+  return nullptr;
+}
+
+void nsChildView::Destroy()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Make sure that no composition is in progress while disconnecting
+  // ourselves from the view.
+  MutexAutoLock lock(mViewTearDownLock);
+
+  if (mOnDestroyCalled)
+    return;
+  mOnDestroyCalled = true;
+
+  // Stuff below may delete the last ref to this
+  nsCOMPtr<nsIWidget> kungFuDeathGrip(this);
+
+  [mView widgetDestroyed];
+
+  nsBaseWidget::Destroy();
+
+  NotifyWindowDestroyed();
+  mParentWidget = nil;
+
+  TearDownView();
+
+  nsBaseWidget::OnDestroy();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+#pragma mark -
+
+#if 0
+static void PrintViewHierarchy(NSView *view)
+{
+  while (view) {
+    NSLog(@"  view is %x, frame %@", view, NSStringFromRect([view frame]));
+    view = [view superview];
+  }
+}
+#endif
+
+// Return native data according to aDataType
+void* nsChildView::GetNativeData(uint32_t aDataType)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSNULL;
+
+  void* retVal = nullptr;
+
+  switch (aDataType)
+  {
+    case NS_NATIVE_WIDGET:
+    case NS_NATIVE_DISPLAY:
+      retVal = (void*)mView;
+      break;
+
+    case NS_NATIVE_WINDOW:
+      retVal = [mView window];
+      break;
+
+    case NS_NATIVE_GRAPHIC:
+      NS_ERROR("Requesting NS_NATIVE_GRAPHIC on a Mac OS X child view!");
+      retVal = nullptr;
+      break;
+
+    case NS_NATIVE_OFFSETX:
+      retVal = 0;
+      break;
+
+    case NS_NATIVE_OFFSETY:
+      retVal = 0;
+      break;
+
+    case NS_RAW_NATIVE_IME_CONTEXT:
+      retVal = GetPseudoIMEContext();
+      if (retVal) {
+        break;
+      }
+      retVal = [mView inputContext];
+      // If input context isn't available on this widget, we should set |this|
+      // instead of nullptr since if this returns nullptr, IMEStateManager
+      // cannot manage composition with TextComposition instance.  Although,
+      // this case shouldn't occur.
+      if (NS_WARN_IF(!retVal)) {
+        retVal = this;
+      }
+      break;
+  }
+
+  return retVal;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSNULL;
+}
+
+#pragma mark -
+
+nsTransparencyMode nsChildView::GetTransparencyMode()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  nsCocoaWindow* windowWidget = GetXULWindowWidget();
+  return windowWidget ? windowWidget->GetTransparencyMode() : eTransparencyOpaque;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(eTransparencyOpaque);
+}
+
+// This is called by nsContainerFrame on the root widget for all window types
+// except popup windows (when nsCocoaWindow::SetTransparencyMode is used instead).
+void nsChildView::SetTransparencyMode(nsTransparencyMode aMode)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  nsCocoaWindow* windowWidget = GetXULWindowWidget();
+  if (windowWidget) {
+    windowWidget->SetTransparencyMode(aMode);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+bool nsChildView::IsVisible() const
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (!mVisible) {
+    return mVisible;
+  }
+
+  // mVisible does not accurately reflect the state of a hidden tabbed view
+  // so verify that the view has a window as well
+  // then check native widget hierarchy visibility
+  return ([mView window] != nil) && !NSIsEmptyRect([mView visibleRect]);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+// Some NSView methods (e.g. setFrame and setHidden) invalidate the view's
+// bounds in our window. However, we don't want these invalidations because
+// they are unnecessary and because they actually slow us down since we
+// block on the compositor inside drawRect.
+// When we actually need something invalidated, there will be an explicit call
+// to Invalidate from Gecko, so turning these automatic invalidations off
+// won't hurt us in the non-OMTC case.
+// The invalidations inside these NSView methods happen via a call to the
+// private method -[NSWindow _setNeedsDisplayInRect:]. Our BaseWindow
+// implementation of that method is augmented to let us ignore those calls
+// using -[BaseWindow disable/enableSetNeedsDisplay].
+static void
+ManipulateViewWithoutNeedingDisplay(NSView* aView, void (^aCallback)())
+{
+  BaseWindow* win = nil;
+  if ([[aView window] isKindOfClass:[BaseWindow class]]) {
+    win = (BaseWindow*)[aView window];
+  }
+  [win disableSetNeedsDisplay];
+  aCallback();
+  [win enableSetNeedsDisplay];
+}
+
+// Hide or show this component
+NS_IMETHODIMP nsChildView::Show(bool aState)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (aState != mVisible) {
+    // Provide an autorelease pool because this gets called during startup
+    // on the "hidden window", resulting in cocoa object leakage if there's
+    // no pool in place.
+    nsAutoreleasePool localPool;
+
+    ManipulateViewWithoutNeedingDisplay(mView, ^{
+      [mView setHidden:!aState];
+    });
+
+    mVisible = aState;
+  }
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Change the parent of this widget
+NS_IMETHODIMP
+nsChildView::SetParent(nsIWidget* aNewParent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (mOnDestroyCalled)
+    return NS_OK;
+
+  nsCOMPtr<nsIWidget> kungFuDeathGrip(this);
+
+  if (mParentWidget) {
+    mParentWidget->RemoveChild(this);
+  }
+
+  if (aNewParent) {
+    ReparentNativeWidget(aNewParent);
+  } else {
+    [mView removeFromSuperview];
+    mParentView = nil;
+  }
+
+  mParentWidget = aNewParent;
+
+  if (mParentWidget) {
+    mParentWidget->AddChild(this);
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void
+nsChildView::ReparentNativeWidget(nsIWidget* aNewParent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_PRECONDITION(aNewParent, "");
+
+  if (mOnDestroyCalled)
+    return;
+
+  NSView<mozView>* newParentView =
+   (NSView<mozView>*)aNewParent->GetNativeData(NS_NATIVE_WIDGET);
+  NS_ENSURE_TRUE_VOID(newParentView);
+
+  // we hold a ref to mView, so this is safe
+  [mView removeFromSuperview];
+  mParentView = newParentView;
+  [mParentView addSubview:mView];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsChildView::ResetParent()
+{
+  if (!mOnDestroyCalled) {
+    if (mParentWidget)
+      mParentWidget->RemoveChild(this);
+    if (mView)
+      [mView removeFromSuperview];
+  }
+  mParentWidget = nullptr;
+}
+
+nsIWidget*
+nsChildView::GetParent()
+{
+  return mParentWidget;
+}
+
+float
+nsChildView::GetDPI()
+{
+  NSWindow* window = [mView window];
+  if (window && [window isKindOfClass:[BaseWindow class]]) {
+    return [(BaseWindow*)window getDPI];
+  }
+
+  return 96.0;
+}
+
+NS_IMETHODIMP nsChildView::Enable(bool aState)
+{
+  return NS_OK;
+}
+
+bool nsChildView::IsEnabled() const
+{
+  return true;
+}
+
+NS_IMETHODIMP nsChildView::SetFocus(bool aRaise)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSWindow* window = [mView window];
+  if (window)
+    [window makeFirstResponder:mView];
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Override to set the cursor on the mac
+NS_IMETHODIMP nsChildView::SetCursor(nsCursor aCursor)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if ([mView isDragInProgress])
+    return NS_OK; // Don't change the cursor during dragging.
+
+  nsBaseWidget::SetCursor(aCursor);
+  return [[nsCursorManager sharedInstance] setCursor:aCursor];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// implement to fix "hidden virtual function" warning
+NS_IMETHODIMP nsChildView::SetCursor(imgIContainer* aCursor,
+                                      uint32_t aHotspotX, uint32_t aHotspotY)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  nsBaseWidget::SetCursor(aCursor, aHotspotX, aHotspotY);
+  return [[nsCursorManager sharedInstance] setCursorWithImage:aCursor hotSpotX:aHotspotX hotSpotY:aHotspotY scaleFactor:BackingScaleFactor()];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+#pragma mark -
+
+// Get this component dimension
+LayoutDeviceIntRect
+nsChildView::GetBounds()
+{
+  return !mView ? mBounds : CocoaPointsToDevPixels([mView frame]);
+}
+
+LayoutDeviceIntRect
+nsChildView::GetClientBounds()
+{
+  LayoutDeviceIntRect rect = GetBounds();
+  if (!mParentWidget) {
+    // For top level widgets we want the position on screen, not the position
+    // of this view inside the window.
+    rect.MoveTo(WidgetToScreenOffset());
+  }
+  return rect;
+}
+
+LayoutDeviceIntRect
+nsChildView::GetScreenBounds()
+{
+  LayoutDeviceIntRect rect = GetBounds();
+  rect.MoveTo(WidgetToScreenOffset());
+  return rect;
+}
+
+double
+nsChildView::GetDefaultScaleInternal()
+{
+  return BackingScaleFactor();
+}
+
+CGFloat
+nsChildView::BackingScaleFactor() const
+{
+  if (mBackingScaleFactor > 0.0) {
+    return mBackingScaleFactor;
+  }
+  if (!mView) {
+    return 1.0;
+  }
+  mBackingScaleFactor = nsCocoaUtils::GetBackingScaleFactor(mView);
+  return mBackingScaleFactor;
+}
+
+void
+nsChildView::BackingScaleFactorChanged()
+{
+  CGFloat newScale = nsCocoaUtils::GetBackingScaleFactor(mView);
+
+  // ignore notification if it hasn't really changed (or maybe we have
+  // disabled HiDPI mode via prefs)
+  if (mBackingScaleFactor == newScale) {
+    return;
+  }
+
+  mBackingScaleFactor = newScale;
+  NSRect frame = [mView frame];
+  mBounds = nsCocoaUtils::CocoaRectToGeckoRectDevPix(frame, newScale);
+
+  if (mWidgetListener && !mWidgetListener->GetXULWindow()) {
+    nsIPresShell* presShell = mWidgetListener->GetPresShell();
+    if (presShell) {
+      presShell->BackingScaleFactorChanged();
+    }
+  }
+}
+
+int32_t
+nsChildView::RoundsWidgetCoordinatesTo()
+{
+  if (BackingScaleFactor() == 2.0) {
+    return 2;
+  }
+  return 1;
+}
+
+// Move this component, aX and aY are in the parent widget coordinate system
+NS_IMETHODIMP nsChildView::Move(double aX, double aY)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  int32_t x = NSToIntRound(aX);
+  int32_t y = NSToIntRound(aY);
+
+  if (!mView || (mBounds.x == x && mBounds.y == y))
+    return NS_OK;
+
+  mBounds.x = x;
+  mBounds.y = y;
+
+  ManipulateViewWithoutNeedingDisplay(mView, ^{
+    [mView setFrame:DevPixelsToCocoaPoints(mBounds)];
+  });
+
+  NotifyRollupGeometryChange();
+  ReportMoveEvent();
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsChildView::Resize(double aWidth, double aHeight, bool aRepaint)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  int32_t width = NSToIntRound(aWidth);
+  int32_t height = NSToIntRound(aHeight);
+
+  if (!mView || (mBounds.width == width && mBounds.height == height))
+    return NS_OK;
+
+  mBounds.width  = width;
+  mBounds.height = height;
+
+  ManipulateViewWithoutNeedingDisplay(mView, ^{
+    [mView setFrame:DevPixelsToCocoaPoints(mBounds)];
+  });
+
+  if (mVisible && aRepaint) {
+    [[mView pixelHostingView] setNeedsDisplay:YES];
+  }
+
+  NotifyRollupGeometryChange();
+  ReportSizeEvent();
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsChildView::Resize(double aX, double aY,
+                                  double aWidth, double aHeight, bool aRepaint)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  int32_t x = NSToIntRound(aX);
+  int32_t y = NSToIntRound(aY);
+  int32_t width = NSToIntRound(aWidth);
+  int32_t height = NSToIntRound(aHeight);
+
+  BOOL isMoving = (mBounds.x != x || mBounds.y != y);
+  BOOL isResizing = (mBounds.width != width || mBounds.height != height);
+  if (!mView || (!isMoving && !isResizing))
+    return NS_OK;
+
+  if (isMoving) {
+    mBounds.x = x;
+    mBounds.y = y;
+  }
+  if (isResizing) {
+    mBounds.width  = width;
+    mBounds.height = height;
+  }
+
+  ManipulateViewWithoutNeedingDisplay(mView, ^{
+    [mView setFrame:DevPixelsToCocoaPoints(mBounds)];
+  });
+
+  if (mVisible && aRepaint) {
+    [[mView pixelHostingView] setNeedsDisplay:YES];
+  }
+
+  NotifyRollupGeometryChange();
+  if (isMoving) {
+    ReportMoveEvent();
+    if (mOnDestroyCalled)
+      return NS_OK;
+  }
+  if (isResizing)
+    ReportSizeEvent();
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+static const int32_t resizeIndicatorWidth = 15;
+static const int32_t resizeIndicatorHeight = 15;
+bool nsChildView::ShowsResizeIndicator(LayoutDeviceIntRect* aResizerRect)
+{
+  NSView *topLevelView = mView, *superView = nil;
+  while ((superView = [topLevelView superview]))
+    topLevelView = superView;
+
+  if (![[topLevelView window] showsResizeIndicator] ||
+      !([[topLevelView window] styleMask] & NSResizableWindowMask))
+    return false;
+
+  if (aResizerRect) {
+    NSSize bounds = [topLevelView bounds].size;
+    NSPoint corner = NSMakePoint(bounds.width, [topLevelView isFlipped] ? bounds.height : 0);
+    corner = [topLevelView convertPoint:corner toView:mView];
+    aResizerRect->SetRect(NSToIntRound(corner.x) - resizeIndicatorWidth,
+                          NSToIntRound(corner.y) - resizeIndicatorHeight,
+                          resizeIndicatorWidth, resizeIndicatorHeight);
+  }
+  return true;
+}
+
+nsresult nsChildView::SynthesizeNativeKeyEvent(int32_t aNativeKeyboardLayout,
+                                               int32_t aNativeKeyCode,
+                                               uint32_t aModifierFlags,
+                                               const nsAString& aCharacters,
+                                               const nsAString& aUnmodifiedCharacters,
+                                               nsIObserver* aObserver)
+{
+  AutoObserverNotifier notifier(aObserver, "keyevent");
+  return mTextInputHandler->SynthesizeNativeKeyEvent(aNativeKeyboardLayout,
+                                                     aNativeKeyCode,
+                                                     aModifierFlags,
+                                                     aCharacters,
+                                                     aUnmodifiedCharacters);
+}
+
+nsresult nsChildView::SynthesizeNativeMouseEvent(LayoutDeviceIntPoint aPoint,
+                                                 uint32_t aNativeMessage,
+                                                 uint32_t aModifierFlags,
+                                                 nsIObserver* aObserver)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  AutoObserverNotifier notifier(aObserver, "mouseevent");
+
+  NSPoint pt =
+    nsCocoaUtils::DevPixelsToCocoaPoints(aPoint, BackingScaleFactor());
+
+  // Move the mouse cursor to the requested position and reconnect it to the mouse.
+  CGWarpMouseCursorPosition(NSPointToCGPoint(pt));
+  CGAssociateMouseAndMouseCursorPosition(true);
+
+  // aPoint is given with the origin on the top left, but convertScreenToBase
+  // expects a point in a coordinate system that has its origin on the bottom left.
+  NSPoint screenPoint = NSMakePoint(pt.x, nsCocoaUtils::FlippedScreenY(pt.y));
+  NSPoint windowPoint =
+    nsCocoaUtils::ConvertPointFromScreen([mView window], screenPoint);
+
+  NSEvent* event = [NSEvent mouseEventWithType:(NSEventType)aNativeMessage
+                                      location:windowPoint
+                                 modifierFlags:aModifierFlags
+                                     timestamp:[[NSProcessInfo processInfo] systemUptime]
+                                  windowNumber:[[mView window] windowNumber]
+                                       context:nil
+                                   eventNumber:0
+                                    clickCount:1
+                                      pressure:0.0];
+
+  if (!event)
+    return NS_ERROR_FAILURE;
+
+  if ([[mView window] isKindOfClass:[BaseWindow class]]) {
+    // Tracking area events don't end up in their tracking areas when sent
+    // through [NSApp sendEvent:], so pass them directly to the right methods.
+    BaseWindow* window = (BaseWindow*)[mView window];
+    if (aNativeMessage == NSMouseEntered) {
+      [window mouseEntered:event];
+      return NS_OK;
+    }
+    if (aNativeMessage == NSMouseExited) {
+      [window mouseExited:event];
+      return NS_OK;
+    }
+    if (aNativeMessage == NSMouseMoved) {
+      [window mouseMoved:event];
+      return NS_OK;
+    }
+  }
+
+  [NSApp sendEvent:event];
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult nsChildView::SynthesizeNativeMouseScrollEvent(mozilla::LayoutDeviceIntPoint aPoint,
+                                                       uint32_t aNativeMessage,
+                                                       double aDeltaX,
+                                                       double aDeltaY,
+                                                       double aDeltaZ,
+                                                       uint32_t aModifierFlags,
+                                                       uint32_t aAdditionalFlags,
+                                                       nsIObserver* aObserver)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  AutoObserverNotifier notifier(aObserver, "mousescrollevent");
+
+  NSPoint pt =
+    nsCocoaUtils::DevPixelsToCocoaPoints(aPoint, BackingScaleFactor());
+
+  // Move the mouse cursor to the requested position and reconnect it to the mouse.
+  CGWarpMouseCursorPosition(NSPointToCGPoint(pt));
+  CGAssociateMouseAndMouseCursorPosition(true);
+
+  // Mostly copied from http://stackoverflow.com/a/6130349
+  CGScrollEventUnit units =
+    (aAdditionalFlags & nsIDOMWindowUtils::MOUSESCROLL_SCROLL_LINES)
+    ? kCGScrollEventUnitLine : kCGScrollEventUnitPixel;
+  CGEventRef cgEvent = CGEventCreateScrollWheelEvent(NULL, units, 3, aDeltaY, aDeltaX, aDeltaZ);
+  if (!cgEvent) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CGEventPost(kCGHIDEventTap, cgEvent);
+  CFRelease(cgEvent);
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult nsChildView::SynthesizeNativeTouchPoint(uint32_t aPointerId,
+                                                 TouchPointerState aPointerState,
+                                                 mozilla::LayoutDeviceIntPoint aPoint,
+                                                 double aPointerPressure,
+                                                 uint32_t aPointerOrientation,
+                                                 nsIObserver* aObserver)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  AutoObserverNotifier notifier(aObserver, "touchpoint");
+
+  MOZ_ASSERT(NS_IsMainThread());
+  if (aPointerState == TOUCH_HOVER) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  if (!mSynthesizedTouchInput) {
+    mSynthesizedTouchInput = MakeUnique<MultiTouchInput>();
+  }
+
+  LayoutDeviceIntPoint pointInWindow = aPoint - WidgetToScreenOffset();
+  MultiTouchInput inputToDispatch = UpdateSynthesizedTouchState(
+      mSynthesizedTouchInput.get(), PR_IntervalNow(), TimeStamp::Now(),
+      aPointerId, aPointerState, pointInWindow, aPointerPressure,
+      aPointerOrientation);
+  DispatchTouchInput(inputToDispatch);
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// First argument has to be an NSMenu representing the application's top-level
+// menu bar. The returned item is *not* retained.
+static NSMenuItem* NativeMenuItemWithLocation(NSMenu* menubar, NSString* locationString)
+{
+  NSArray* indexes = [locationString componentsSeparatedByString:@"|"];
+  unsigned int indexCount = [indexes count];
+  if (indexCount == 0)
+    return nil;
+
+  NSMenu* currentSubmenu = [NSApp mainMenu];
+  for (unsigned int i = 0; i < indexCount; i++) {
+    int targetIndex;
+    // We remove the application menu from consideration for the top-level menu
+    if (i == 0)
+      targetIndex = [[indexes objectAtIndex:i] intValue] + 1;
+    else
+      targetIndex = [[indexes objectAtIndex:i] intValue];
+    int itemCount = [currentSubmenu numberOfItems];
+    if (targetIndex < itemCount) {
+      NSMenuItem* menuItem = [currentSubmenu itemAtIndex:targetIndex];
+      // if this is the last index just return the menu item
+      if (i == (indexCount - 1))
+        return menuItem;
+      // if this is not the last index find the submenu and keep going
+      if ([menuItem hasSubmenu])
+        currentSubmenu = [menuItem submenu];
+      else
+        return nil;
+    }
+  }
+
+  return nil;
+}
+
+// Used for testing native menu system structure and event handling.
+NS_IMETHODIMP nsChildView::ActivateNativeMenuItemAt(const nsAString& indexString)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSString* locationString = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(indexString.BeginReading())
+                                                     length:indexString.Length()];
+  NSMenuItem* item = NativeMenuItemWithLocation([NSApp mainMenu], locationString);
+  // We can't perform an action on an item with a submenu, that will raise
+  // an obj-c exception.
+  if (item && ![item hasSubmenu]) {
+    NSMenu* parent = [item menu];
+    if (parent) {
+      // NSLog(@"Performing action for native menu item titled: %@\n",
+      //       [[currentSubmenu itemAtIndex:targetIndex] title]);
+      [parent performActionForItemAtIndex:[parent indexOfItem:item]];
+      return NS_OK;
+    }
+  }
+  return NS_ERROR_FAILURE;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Used for testing native menu system structure and event handling.
+NS_IMETHODIMP nsChildView::ForceUpdateNativeMenuAt(const nsAString& indexString)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  nsCocoaWindow *widget = GetXULWindowWidget();
+  if (widget) {
+    nsMenuBarX* mb = widget->GetMenuBar();
+    if (mb) {
+      if (indexString.IsEmpty())
+        mb->ForceNativeMenuReload();
+      else
+        mb->ForceUpdateNativeMenuAt(indexString);
+    }
+  }
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+#pragma mark -
+
+#ifdef INVALIDATE_DEBUGGING
+
+static Boolean KeyDown(const UInt8 theKey)
+{
+  KeyMap map;
+  GetKeys(map);
+  return ((*((UInt8 *)map + (theKey >> 3)) >> (theKey & 7)) & 1) != 0;
+}
+
+static Boolean caps_lock()
+{
+  return KeyDown(0x39);
+}
+
+static void blinkRect(Rect* r)
+{
+  StRegionFromPool oldClip;
+  if (oldClip != NULL)
+    ::GetClip(oldClip);
+
+  ::ClipRect(r);
+  ::InvertRect(r);
+  UInt32 end = ::TickCount() + 5;
+  while (::TickCount() < end) ;
+  ::InvertRect(r);
+
+  if (oldClip != NULL)
+    ::SetClip(oldClip);
+}
+
+static void blinkRgn(RgnHandle rgn)
+{
+  StRegionFromPool oldClip;
+  if (oldClip != NULL)
+    ::GetClip(oldClip);
+
+  ::SetClip(rgn);
+  ::InvertRgn(rgn);
+  UInt32 end = ::TickCount() + 5;
+  while (::TickCount() < end) ;
+  ::InvertRgn(rgn);
+
+  if (oldClip != NULL)
+    ::SetClip(oldClip);
+}
+
+#endif
+
+// Invalidate this component's visible area
+NS_IMETHODIMP nsChildView::Invalidate(const LayoutDeviceIntRect& aRect)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!mView || !mVisible)
+    return NS_OK;
+
+  NS_ASSERTION(GetLayerManager()->GetBackendType() != LayersBackend::LAYERS_CLIENT,
+               "Shouldn't need to invalidate with accelerated OMTC layers!");
+
+  [[mView pixelHostingView] setNeedsDisplayInRect:DevPixelsToCocoaPoints(aRect)];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+bool
+nsChildView::WidgetTypeSupportsAcceleration()
+{
+  // Don't use OpenGL for transparent windows or for popup windows.
+  return mView && [[mView window] isOpaque] &&
+         ![[mView window] isKindOfClass:[PopupWindow class]];
+}
+
+bool
+nsChildView::ShouldUseOffMainThreadCompositing()
+{
+  // Don't use OMTC for transparent windows or for popup windows.
+  if (!mView || ![[mView window] isOpaque] ||
+      [[mView window] isKindOfClass:[PopupWindow class]])
+    return false;
+
+  return nsBaseWidget::ShouldUseOffMainThreadCompositing();
+}
+
+inline uint16_t COLOR8TOCOLOR16(uint8_t color8)
+{
+  // return (color8 == 0xFF ? 0xFFFF : (color8 << 8));
+  return (color8 << 8) | color8;  /* (color8 * 257) == (color8 * 0x0101) */
+}
+
+#pragma mark -
+
+nsresult nsChildView::ConfigureChildren(const nsTArray<Configuration>& aConfigurations)
+{
+  return NS_OK;
+}
+
+// Invokes callback and ProcessEvent methods on Event Listener object
+NS_IMETHODIMP nsChildView::DispatchEvent(WidgetGUIEvent* event,
+                                         nsEventStatus& aStatus)
+{
+  RefPtr<nsChildView> kungFuDeathGrip(this);
+
+#ifdef DEBUG
+  debug_DumpEvent(stdout, event->mWidget, event, "something", 0);
+#endif
+
+  NS_ASSERTION(!(mTextInputHandler && mTextInputHandler->IsIMEComposing() &&
+                 event->HasKeyEventMessage()),
+    "Any key events should not be fired during IME composing");
+
+  if (event->mFlags.mIsSynthesizedForTests) {
+    WidgetKeyboardEvent* keyEvent = event->AsKeyboardEvent();
+    if (keyEvent) {
+      nsresult rv = mTextInputHandler->AttachNativeKeyEvent(*keyEvent);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+  }
+
+  aStatus = nsEventStatus_eIgnore;
+
+  nsIWidgetListener* listener = mWidgetListener;
+
+  // If the listener is NULL, check if the parent is a popup. If it is, then
+  // this child is the popup content view attached to a popup. Get the
+  // listener from the parent popup instead.
+  nsCOMPtr<nsIWidget> parentWidget = mParentWidget;
+  if (!listener && parentWidget) {
+    if (parentWidget->WindowType() == eWindowType_popup) {
+      // Check just in case event->mWidget isn't this widget
+      if (event->mWidget) {
+        listener = event->mWidget->GetWidgetListener();
+      }
+      if (!listener) {
+        event->mWidget = parentWidget;
+        listener = parentWidget->GetWidgetListener();
+      }
+    }
+  }
+
+  if (listener)
+    aStatus = listener->HandleEvent(event, mUseAttachedEvents);
+
+  return NS_OK;
+}
+
+bool nsChildView::DispatchWindowEvent(WidgetGUIEvent& event)
+{
+  nsEventStatus status;
+  DispatchEvent(&event, status);
+  return ConvertStatus(status);
+}
+
+nsIWidget*
+nsChildView::GetWidgetForListenerEvents()
+{
+  // If there is no listener, use the parent popup's listener if that exists.
+  if (!mWidgetListener && mParentWidget &&
+      mParentWidget->WindowType() == eWindowType_popup) {
+    return mParentWidget;
+  }
+
+  return this;
+}
+
+void nsChildView::WillPaintWindow()
+{
+  nsCOMPtr<nsIWidget> widget = GetWidgetForListenerEvents();
+
+  nsIWidgetListener* listener = widget->GetWidgetListener();
+  if (listener) {
+    listener->WillPaintWindow(widget);
+  }
+}
+
+bool nsChildView::PaintWindow(LayoutDeviceIntRegion aRegion)
+{
+  nsCOMPtr<nsIWidget> widget = GetWidgetForListenerEvents();
+
+  nsIWidgetListener* listener = widget->GetWidgetListener();
+  if (!listener)
+    return false;
+
+  bool returnValue = false;
+  bool oldDispatchPaint = mIsDispatchPaint;
+  mIsDispatchPaint = true;
+  returnValue = listener->PaintWindow(widget, aRegion);
+
+  listener = widget->GetWidgetListener();
+  if (listener) {
+    listener->DidPaintWindow();
+  }
+
+  mIsDispatchPaint = oldDispatchPaint;
+  return returnValue;
+}
+
+bool
+nsChildView::PaintWindowInContext(CGContextRef aContext, const LayoutDeviceIntRegion& aRegion, gfx::IntSize aSurfaceSize)
+{
+  if (!mBackingSurface || mBackingSurface->GetSize() != aSurfaceSize) {
+    mBackingSurface =
+      gfxPlatform::GetPlatform()->CreateOffscreenContentDrawTarget(aSurfaceSize,
+                                                                   gfx::SurfaceFormat::B8G8R8A8);
+    if (!mBackingSurface) {
+      return false;
+    }
+  }
+
+  RefPtr<gfxContext> targetContext = gfxContext::CreateOrNull(mBackingSurface);
+  MOZ_ASSERT(targetContext); // already checked the draw target above
+
+  // Set up the clip region and clear existing contents in the backing surface.
+  targetContext->NewPath();
+  for (auto iter = aRegion.RectIter(); !iter.Done(); iter.Next()) {
+    const LayoutDeviceIntRect& r = iter.Get();
+    targetContext->Rectangle(gfxRect(r.x, r.y, r.width, r.height));
+    mBackingSurface->ClearRect(gfx::Rect(r.ToUnknownRect()));
+  }
+  targetContext->Clip();
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(mView);
+  bool painted = false;
+  if (GetLayerManager()->GetBackendType() == LayersBackend::LAYERS_BASIC) {
+    nsBaseWidget::AutoLayerManagerSetup
+      setupLayerManager(this, targetContext, BufferMode::BUFFER_NONE);
+    painted = PaintWindow(aRegion);
+  } else if (GetLayerManager()->GetBackendType() == LayersBackend::LAYERS_CLIENT) {
+    // We only need this so that we actually get DidPaintWindow fired
+    painted = PaintWindow(aRegion);
+  }
+
+  uint8_t* data;
+  gfx::IntSize size;
+  int32_t stride;
+  gfx::SurfaceFormat format;
+
+  if (!mBackingSurface->LockBits(&data, &size, &stride, &format)) {
+    return false;
+  }
+
+  // Draw the backing surface onto the window.
+  CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, data, stride * size.height, NULL);
+  NSColorSpace* colorSpace = [[mView window] colorSpace];
+  CGImageRef image = CGImageCreate(size.width, size.height, 8, 32, stride,
+                                   [colorSpace CGColorSpace],
+                                   kCGBitmapByteOrder32Host | kCGImageAlphaPremultipliedFirst,
+                                   provider, NULL, false, kCGRenderingIntentDefault);
+  CGContextSaveGState(aContext);
+  CGContextTranslateCTM(aContext, 0, size.height);
+  CGContextScaleCTM(aContext, 1, -1);
+  CGContextSetBlendMode(aContext, kCGBlendModeCopy);
+  CGContextDrawImage(aContext, CGRectMake(0, 0, size.width, size.height), image);
+  CGImageRelease(image);
+  CGDataProviderRelease(provider);
+  CGContextRestoreGState(aContext);
+
+  mBackingSurface->ReleaseBits(data);
+
+  return painted;
+}
+
+#pragma mark -
+
+void nsChildView::ReportMoveEvent()
+{
+   NotifyWindowMoved(mBounds.x, mBounds.y);
+}
+
+void nsChildView::ReportSizeEvent()
+{
+  if (mWidgetListener)
+    mWidgetListener->WindowResized(this, mBounds.width, mBounds.height);
+}
+
+#pragma mark -
+
+LayoutDeviceIntPoint nsChildView::GetClientOffset()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NSPoint origin = [mView convertPoint:NSMakePoint(0, 0) toView:nil];
+  origin.y = [[mView window] frame].size.height - origin.y;
+  return CocoaPointsToDevPixels(origin);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(LayoutDeviceIntPoint(0, 0));
+}
+
+//    Return the offset between this child view and the screen.
+//    @return       -- widget origin in device-pixel coords
+LayoutDeviceIntPoint nsChildView::WidgetToScreenOffset()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NSPoint origin = NSMakePoint(0, 0);
+
+  // 1. First translate view origin point into window coords.
+  // The returned point is in bottom-left coordinates.
+  origin = [mView convertPoint:origin toView:nil];
+
+  // 2. We turn the window-coord rect's origin into screen (still bottom-left) coords.
+  origin = nsCocoaUtils::ConvertPointToScreen([mView window], origin);
+
+  // 3. Since we're dealing in bottom-left coords, we need to make it top-left coords
+  //    before we pass it back to Gecko.
+  FlipCocoaScreenCoordinate(origin);
+
+  // convert to device pixels
+  return CocoaPointsToDevPixels(origin);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(LayoutDeviceIntPoint(0,0));
+}
+
+NS_IMETHODIMP nsChildView::SetTitle(const nsAString& title)
+{
+  // child views don't have titles
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsChildView::GetAttention(int32_t aCycleCount)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  [NSApp requestUserAttention:NSInformationalRequest];
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+/* static */
+bool nsChildView::DoHasPendingInputEvent()
+{
+  return sLastInputEventCount != GetCurrentInputEventCount();
+}
+
+/* static */
+uint32_t nsChildView::GetCurrentInputEventCount()
+{
+  // Can't use kCGAnyInputEventType because that updates too rarely for us (and
+  // always in increments of 30+!) and because apparently it's sort of broken
+  // on Tiger.  So just go ahead and query the counters we care about.
+  static const CGEventType eventTypes[] = {
+    kCGEventLeftMouseDown,
+    kCGEventLeftMouseUp,
+    kCGEventRightMouseDown,
+    kCGEventRightMouseUp,
+    kCGEventMouseMoved,
+    kCGEventLeftMouseDragged,
+    kCGEventRightMouseDragged,
+    kCGEventKeyDown,
+    kCGEventKeyUp,
+    kCGEventScrollWheel,
+    kCGEventTabletPointer,
+    kCGEventOtherMouseDown,
+    kCGEventOtherMouseUp,
+    kCGEventOtherMouseDragged
+  };
+
+  uint32_t eventCount = 0;
+  for (uint32_t i = 0; i < ArrayLength(eventTypes); ++i) {
+    eventCount +=
+      CGEventSourceCounterForEventType(kCGEventSourceStateCombinedSessionState,
+                                       eventTypes[i]);
+  }
+  return eventCount;
+}
+
+/* static */
+void nsChildView::UpdateCurrentInputEventCount()
+{
+  sLastInputEventCount = GetCurrentInputEventCount();
+}
+
+bool nsChildView::HasPendingInputEvent()
+{
+  return DoHasPendingInputEvent();
+}
+
+#pragma mark -
+
+NS_IMETHODIMP
+nsChildView::StartPluginIME(const mozilla::WidgetKeyboardEvent& aKeyboardEvent,
+                            int32_t aPanelX, int32_t aPanelY,
+                            nsString& aCommitted)
+{
+  NS_ENSURE_TRUE(mView, NS_ERROR_NOT_AVAILABLE);
+
+  ComplexTextInputPanel* ctiPanel =
+    ComplexTextInputPanel::GetSharedComplexTextInputPanel();
+
+  ctiPanel->PlacePanel(aPanelX, aPanelY);
+  // We deliberately don't use TextInputHandler::GetCurrentKeyEvent() to
+  // obtain the NSEvent* we pass to InterpretKeyEvent().  This works fine in
+  // non-e10s mode.  But in e10s mode TextInputHandler::HandleKeyDownEvent()
+  // has already returned, so the relevant KeyEventState* (and its NSEvent*)
+  // is already out of scope.  Furthermore we don't *need* to use it.
+  // StartPluginIME() is only ever called to start a new IME session when none
+  // currently exists.  So nested IME should never reach here, and so it should
+  // be fine to use the last key-down event received by -[ChildView keyDown:]
+  // (as we currently do).
+  ctiPanel->InterpretKeyEvent([(ChildView*)mView lastKeyDownEvent], aCommitted);
+
+  return NS_OK;
+}
+
+void
+nsChildView::SetPluginFocused(bool& aFocused)
+{
+  if (aFocused == mPluginFocused) {
+    return;
+  }
+  if (!aFocused) {
+    ComplexTextInputPanel* ctiPanel =
+      ComplexTextInputPanel::GetSharedComplexTextInputPanel();
+    if (ctiPanel) {
+      ctiPanel->CancelComposition();
+    }
+  }
+  mPluginFocused = aFocused;
+}
+
+NS_IMETHODIMP_(void)
+nsChildView::SetInputContext(const InputContext& aContext,
+                             const InputContextAction& aAction)
+{
+  NS_ENSURE_TRUE_VOID(mTextInputHandler);
+
+  if (mTextInputHandler->IsFocused()) {
+    if (aContext.IsPasswordEditor()) {
+      TextInputHandler::EnableSecureEventInput();
+    } else {
+      TextInputHandler::EnsureSecureEventInputDisabled();
+    }
+  }
+
+  mInputContext = aContext;
+  switch (aContext.mIMEState.mEnabled) {
+    case IMEState::ENABLED:
+    case IMEState::PLUGIN:
+      mTextInputHandler->SetASCIICapableOnly(false);
+      mTextInputHandler->EnableIME(true);
+      if (mInputContext.mIMEState.mOpen != IMEState::DONT_CHANGE_OPEN_STATE) {
+        mTextInputHandler->SetIMEOpenState(
+          mInputContext.mIMEState.mOpen == IMEState::OPEN);
+      }
+      break;
+    case IMEState::DISABLED:
+      mTextInputHandler->SetASCIICapableOnly(false);
+      mTextInputHandler->EnableIME(false);
+      break;
+    case IMEState::PASSWORD:
+      mTextInputHandler->SetASCIICapableOnly(true);
+      mTextInputHandler->EnableIME(false);
+      break;
+    default:
+      NS_ERROR("not implemented!");
+  }
+}
+
+NS_IMETHODIMP_(InputContext)
+nsChildView::GetInputContext()
+{
+  switch (mInputContext.mIMEState.mEnabled) {
+    case IMEState::ENABLED:
+    case IMEState::PLUGIN:
+      if (mTextInputHandler) {
+        mInputContext.mIMEState.mOpen =
+          mTextInputHandler->IsIMEOpened() ? IMEState::OPEN : IMEState::CLOSED;
+        break;
+      }
+      // If mTextInputHandler is null, set CLOSED instead...
+      MOZ_FALLTHROUGH;
+    default:
+      mInputContext.mIMEState.mOpen = IMEState::CLOSED;
+      break;
+  }
+  return mInputContext;
+}
+
+NS_IMETHODIMP_(TextEventDispatcherListener*)
+nsChildView::GetNativeTextEventDispatcherListener()
+{
+  if (NS_WARN_IF(!mTextInputHandler)) {
+    return nullptr;
+  }
+  return mTextInputHandler;
+}
+
+NS_IMETHODIMP
+nsChildView::AttachNativeKeyEvent(mozilla::WidgetKeyboardEvent& aEvent)
+{
+  NS_ENSURE_TRUE(mTextInputHandler, NS_ERROR_NOT_AVAILABLE);
+  return mTextInputHandler->AttachNativeKeyEvent(aEvent);
+}
+
+bool
+nsChildView::ExecuteNativeKeyBindingRemapped(NativeKeyBindingsType aType,
+                                             const WidgetKeyboardEvent& aEvent,
+                                             DoCommandCallback aCallback,
+                                             void* aCallbackData,
+                                             uint32_t aGeckoKeyCode,
+                                             uint32_t aCocoaKeyCode)
+{
+  NSEvent *originalEvent = reinterpret_cast<NSEvent*>(aEvent.mNativeKeyEvent);
+
+  WidgetKeyboardEvent modifiedEvent(aEvent);
+  modifiedEvent.mKeyCode = aGeckoKeyCode;
+
+  unichar ch = nsCocoaUtils::ConvertGeckoKeyCodeToMacCharCode(aGeckoKeyCode);
+  NSString *chars =
+    [[[NSString alloc] initWithCharacters:&ch length:1] autorelease];
+
+  modifiedEvent.mNativeKeyEvent =
+    [NSEvent keyEventWithType:[originalEvent type]
+                     location:[originalEvent locationInWindow]
+                modifierFlags:[originalEvent modifierFlags]
+                    timestamp:[originalEvent timestamp]
+                 windowNumber:[originalEvent windowNumber]
+                      context:[originalEvent context]
+                   characters:chars
+  charactersIgnoringModifiers:chars
+                    isARepeat:[originalEvent isARepeat]
+                      keyCode:aCocoaKeyCode];
+
+  NativeKeyBindings* keyBindings = NativeKeyBindings::GetInstance(aType);
+  return keyBindings->Execute(modifiedEvent, aCallback, aCallbackData);
+}
+
+NS_IMETHODIMP_(bool)
+nsChildView::ExecuteNativeKeyBinding(NativeKeyBindingsType aType,
+                                     const WidgetKeyboardEvent& aEvent,
+                                     DoCommandCallback aCallback,
+                                     void* aCallbackData)
+{
+  // If the key is a cursor-movement arrow, and the current selection has
+  // vertical writing-mode, we'll remap so that the movement command
+  // generated (in terms of characters/lines) will be appropriate for
+  // the physical direction of the arrow.
+  if (aEvent.mKeyCode >= NS_VK_LEFT && aEvent.mKeyCode <= NS_VK_DOWN) {
+    WidgetQueryContentEvent query(true, eQuerySelectedText, this);
+    DispatchWindowEvent(query);
+
+    if (query.mSucceeded && query.mReply.mWritingMode.IsVertical()) {
+      uint32_t geckoKey = 0;
+      uint32_t cocoaKey = 0;
+
+      switch (aEvent.mKeyCode) {
+      case NS_VK_LEFT:
+        if (query.mReply.mWritingMode.IsVerticalLR()) {
+          geckoKey = NS_VK_UP;
+          cocoaKey = kVK_UpArrow;
+        } else {
+          geckoKey = NS_VK_DOWN;
+          cocoaKey = kVK_DownArrow;
+        }
+        break;
+
+      case NS_VK_RIGHT:
+        if (query.mReply.mWritingMode.IsVerticalLR()) {
+          geckoKey = NS_VK_DOWN;
+          cocoaKey = kVK_DownArrow;
+        } else {
+          geckoKey = NS_VK_UP;
+          cocoaKey = kVK_UpArrow;
+        }
+        break;
+
+      case NS_VK_UP:
+        geckoKey = NS_VK_LEFT;
+        cocoaKey = kVK_LeftArrow;
+        break;
+
+      case NS_VK_DOWN:
+        geckoKey = NS_VK_RIGHT;
+        cocoaKey = kVK_RightArrow;
+        break;
+      }
+
+      return ExecuteNativeKeyBindingRemapped(aType, aEvent, aCallback,
+                                             aCallbackData,
+                                             geckoKey, cocoaKey);
+    }
+  }
+
+  NativeKeyBindings* keyBindings = NativeKeyBindings::GetInstance(aType);
+  return keyBindings->Execute(aEvent, aCallback, aCallbackData);
+}
+
+nsIMEUpdatePreference
+nsChildView::GetIMEUpdatePreference()
+{
+  // XXX Shouldn't we move floating window which shows composition string
+  //     when plugin has focus and its parent is scrolled or the window is
+  //     moved?
+  return nsIMEUpdatePreference();
+}
+
+NSView<mozView>* nsChildView::GetEditorView()
+{
+  NSView<mozView>* editorView = mView;
+  // We need to get editor's view. E.g., when the focus is in the bookmark
+  // dialog, the view is <panel> element of the dialog.  At this time, the key
+  // events are processed the parent window's view that has native focus.
+  WidgetQueryContentEvent textContent(true, eQueryTextContent, this);
+  textContent.InitForQueryTextContent(0, 0);
+  DispatchWindowEvent(textContent);
+  if (textContent.mSucceeded && textContent.mReply.mFocusedWidget) {
+    NSView<mozView>* view = static_cast<NSView<mozView>*>(
+      textContent.mReply.mFocusedWidget->GetNativeData(NS_NATIVE_WIDGET));
+    if (view)
+      editorView = view;
+  }
+  return editorView;
+}
+
+#pragma mark -
+
+void
+nsChildView::CreateCompositor()
+{
+  nsBaseWidget::CreateCompositor();
+  if (mCompositorBridgeChild) {
+    [(ChildView *)mView setUsingOMTCompositor:true];
+  }
+}
+
+void
+nsChildView::ConfigureAPZCTreeManager()
+{
+  nsBaseWidget::ConfigureAPZCTreeManager();
+}
+
+void
+nsChildView::ConfigureAPZControllerThread()
+{
+  if (gfxPrefs::AsyncPanZoomSeparateEventThread()) {
+    // The EventThreadRunner is the controller thread, but it doesn't
+    // have a MessageLoop.
+    APZThreadUtils::SetControllerThread(nullptr);
+  } else {
+    nsBaseWidget::ConfigureAPZControllerThread();
+  }
+}
+
+LayoutDeviceIntRect
+nsChildView::RectContainingTitlebarControls()
+{
+  // Start with a thin strip at the top of the window for the highlight line.
+  NSRect rect = NSMakeRect(0, 0, [mView bounds].size.width,
+                           [(ChildView*)mView cornerRadius]);
+
+  // If we draw the titlebar title string, increase the height to the default
+  // titlebar height. This height does not necessarily include all the titlebar
+  // controls because we may have moved them further down, but at least it will
+  // include the whole title text.
+  BaseWindow* window = (BaseWindow*)[mView window];
+  if ([window wantsTitleDrawn] && [window isKindOfClass:[ToolbarWindow class]]) {
+    CGFloat defaultTitlebarHeight = [(ToolbarWindow*)window titlebarHeight];
+    rect.size.height = std::max(rect.size.height, defaultTitlebarHeight);
+  }
+
+  // Add the rects of the titlebar controls.
+  for (id view in [window titlebarControls]) {
+    rect = NSUnionRect(rect, [mView convertRect:[view bounds] fromView:view]);
+  }
+  return CocoaPointsToDevPixels(rect);
+}
+
+void
+nsChildView::PrepareWindowEffects()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  bool canBeOpaque;
+  {
+    MutexAutoLock lock(mEffectsLock);
+    mShowsResizeIndicator = ShowsResizeIndicator(&mResizeIndicatorRect);
+    mHasRoundedBottomCorners = [(ChildView*)mView hasRoundedBottomCorners];
+    CGFloat cornerRadius = [(ChildView*)mView cornerRadius];
+    mDevPixelCornerRadius = cornerRadius * BackingScaleFactor();
+    mIsCoveringTitlebar = [(ChildView*)mView isCoveringTitlebar];
+    NSInteger styleMask = [[mView window] styleMask];
+    bool wasFullscreen = mIsFullscreen;
+    mIsFullscreen = (styleMask & NSFullScreenWindowMask) || !(styleMask & NSTitledWindowMask);
+
+    canBeOpaque = mIsFullscreen && wasFullscreen;
+    if (canBeOpaque && VibrancyManager::SystemSupportsVibrancy()) {
+      canBeOpaque = !EnsureVibrancyManager().HasVibrantRegions();
+    }
+    if (mIsCoveringTitlebar) {
+      mTitlebarRect = RectContainingTitlebarControls();
+      UpdateTitlebarCGContext();
+    }
+  }
+
+  // If we've just transitioned into or out of full screen then update the opacity on our GLContext.
+  if (canBeOpaque != mIsOpaque) {
+    mIsOpaque = canBeOpaque;
+    [(ChildView*)mView setGLOpaque:canBeOpaque];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsChildView::CleanupWindowEffects()
+{
+  mResizerImage = nullptr;
+  mCornerMaskImage = nullptr;
+  mTitlebarImage = nullptr;
+}
+
+bool
+nsChildView::PreRender(WidgetRenderingContext* aContext)
+{
+  UniquePtr<GLManager> manager(GLManager::CreateGLManager(aContext->mLayerManager));
+  if (!manager) {
+    return true;
+  }
+
+  // The lock makes sure that we don't attempt to tear down the view while
+  // compositing. That would make us unable to call postRender on it when the
+  // composition is done, thus keeping the GL context locked forever.
+  mViewTearDownLock.Lock();
+
+  NSOpenGLContext *glContext = GLContextCGL::Cast(manager->gl())->GetNSOpenGLContext();
+
+  if (![(ChildView*)mView preRender:glContext]) {
+    mViewTearDownLock.Unlock();
+    return false;
+  }
+  return true;
+}
+
+void
+nsChildView::PostRender(WidgetRenderingContext* aContext)
+{
+  UniquePtr<GLManager> manager(GLManager::CreateGLManager(aContext->mLayerManager));
+  if (!manager) {
+    return;
+  }
+  NSOpenGLContext *glContext = GLContextCGL::Cast(manager->gl())->GetNSOpenGLContext();
+  [(ChildView*)mView postRender:glContext];
+  mViewTearDownLock.Unlock();
+}
+
+void
+nsChildView::DrawWindowOverlay(WidgetRenderingContext* aContext,
+                               LayoutDeviceIntRect aRect)
+{
+  mozilla::UniquePtr<GLManager> manager(GLManager::CreateGLManager(aContext->mLayerManager));
+  if (manager) {
+    DrawWindowOverlay(manager.get(), aRect);
+  }
+}
+
+void
+nsChildView::DrawWindowOverlay(GLManager* aManager, LayoutDeviceIntRect aRect)
+{
+  GLContext* gl = aManager->gl();
+  ScopedGLState scopedScissorTestState(gl, LOCAL_GL_SCISSOR_TEST, false);
+
+  MaybeDrawTitlebar(aManager);
+  MaybeDrawResizeIndicator(aManager);
+  MaybeDrawRoundedCorners(aManager, aRect);
+}
+
+static void
+ClearRegion(gfx::DrawTarget *aDT, LayoutDeviceIntRegion aRegion)
+{
+  gfxUtils::ClipToRegion(aDT, aRegion.ToUnknownRegion());
+  aDT->ClearRect(gfx::Rect(0, 0, aDT->GetSize().width, aDT->GetSize().height));
+  aDT->PopClip();
+}
+
+static void
+DrawResizer(CGContextRef aCtx)
+{
+  CGContextSetShouldAntialias(aCtx, false);
+  CGPoint points[6];
+  points[0] = CGPointMake(13.0f, 4.0f);
+  points[1] = CGPointMake(3.0f, 14.0f);
+  points[2] = CGPointMake(13.0f, 8.0f);
+  points[3] = CGPointMake(7.0f, 14.0f);
+  points[4] = CGPointMake(13.0f, 12.0f);
+  points[5] = CGPointMake(11.0f, 14.0f);
+  CGContextSetRGBStrokeColor(aCtx, 0.00f, 0.00f, 0.00f, 0.15f);
+  CGContextStrokeLineSegments(aCtx, points, 6);
+
+  points[0] = CGPointMake(13.0f, 5.0f);
+  points[1] = CGPointMake(4.0f, 14.0f);
+  points[2] = CGPointMake(13.0f, 9.0f);
+  points[3] = CGPointMake(8.0f, 14.0f);
+  points[4] = CGPointMake(13.0f, 13.0f);
+  points[5] = CGPointMake(12.0f, 14.0f);
+  CGContextSetRGBStrokeColor(aCtx, 0.13f, 0.13f, 0.13f, 0.54f);
+  CGContextStrokeLineSegments(aCtx, points, 6);
+
+  points[0] = CGPointMake(13.0f, 6.0f);
+  points[1] = CGPointMake(5.0f, 14.0f);
+  points[2] = CGPointMake(13.0f, 10.0f);
+  points[3] = CGPointMake(9.0f, 14.0f);
+  points[5] = CGPointMake(13.0f, 13.9f);
+  points[4] = CGPointMake(13.0f, 14.0f);
+  CGContextSetRGBStrokeColor(aCtx, 0.84f, 0.84f, 0.84f, 0.55f);
+  CGContextStrokeLineSegments(aCtx, points, 6);
+}
+
+void
+nsChildView::MaybeDrawResizeIndicator(GLManager* aManager)
+{
+  MutexAutoLock lock(mEffectsLock);
+  if (!mShowsResizeIndicator) {
+    return;
+  }
+
+  if (!mResizerImage) {
+    mResizerImage = MakeUnique<RectTextureImage>();
+  }
+
+  LayoutDeviceIntSize size = mResizeIndicatorRect.Size();
+  mResizerImage->UpdateIfNeeded(size, LayoutDeviceIntRegion(), ^(gfx::DrawTarget* drawTarget, const LayoutDeviceIntRegion& updateRegion) {
+    ClearRegion(drawTarget, updateRegion);
+    gfx::BorrowedCGContext borrow(drawTarget);
+    DrawResizer(borrow.cg);
+    borrow.Finish();
+  });
+
+  mResizerImage->Draw(aManager, mResizeIndicatorRect.TopLeft());
+}
+
+// Draw the highlight line at the top of the titlebar.
+// This function draws into the current NSGraphicsContext and assumes flippedness.
+static void
+DrawTitlebarHighlight(NSSize aWindowSize, CGFloat aRadius, CGFloat aDevicePixelWidth)
+{
+  [NSGraphicsContext saveGraphicsState];
+
+  // Set up the clip path. We start with the outer rectangle and cut out a
+  // slightly smaller inner rectangle with rounded corners.
+  // The outer corners of the resulting path will be square, but they will be
+  // masked away in a later step.
+  NSBezierPath* path = [NSBezierPath bezierPath];
+  [path setWindingRule:NSEvenOddWindingRule];
+  NSRect pathRect = NSMakeRect(0, 0, aWindowSize.width, aRadius + 2);
+  [path appendBezierPathWithRect:pathRect];
+  pathRect = NSInsetRect(pathRect, aDevicePixelWidth, aDevicePixelWidth);
+  CGFloat innerRadius = aRadius - aDevicePixelWidth;
+  [path appendBezierPathWithRoundedRect:pathRect xRadius:innerRadius yRadius:innerRadius];
+  [path addClip];
+
+  // Now we fill the path with a subtle highlight gradient.
+  // We don't use NSGradient because it's 5x to 15x slower than the manual fill,
+  // as indicated by the performance test in bug 880620.
+  for (CGFloat y = 0; y < aRadius; y += aDevicePixelWidth) {
+    CGFloat t = y / aRadius;
+    [[NSColor colorWithDeviceWhite:1.0 alpha:0.4 * (1.0 - t)] set];
+    NSRectFillUsingOperation(NSMakeRect(0, y, aWindowSize.width, aDevicePixelWidth), NSCompositeSourceOver);
+  }
+
+  [NSGraphicsContext restoreGraphicsState];
+}
+
+static CGContextRef
+CreateCGContext(const LayoutDeviceIntSize& aSize)
+{
+  CGColorSpaceRef cs = CGColorSpaceCreateDeviceRGB();
+  CGContextRef ctx =
+    CGBitmapContextCreate(NULL,
+                          aSize.width,
+                          aSize.height,
+                          8 /* bitsPerComponent */,
+                          aSize.width * 4,
+                          cs,
+                          kCGBitmapByteOrder32Host | kCGImageAlphaPremultipliedFirst);
+  CGColorSpaceRelease(cs);
+
+  CGContextTranslateCTM(ctx, 0, aSize.height);
+  CGContextScaleCTM(ctx, 1, -1);
+  CGContextSetInterpolationQuality(ctx, kCGInterpolationLow);
+
+  return ctx;
+}
+
+LayoutDeviceIntSize
+TextureSizeForSize(const LayoutDeviceIntSize& aSize)
+{
+  return LayoutDeviceIntSize(RoundUpPow2(aSize.width),
+                             RoundUpPow2(aSize.height));
+}
+
+// When this method is entered, mEffectsLock is already being held.
+void
+nsChildView::UpdateTitlebarCGContext()
+{
+  if (mTitlebarRect.IsEmpty()) {
+    ReleaseTitlebarCGContext();
+    return;
+  }
+
+  NSRect titlebarRect = DevPixelsToCocoaPoints(mTitlebarRect);
+  NSRect dirtyRect = [mView convertRect:[(BaseWindow*)[mView window] getAndResetNativeDirtyRect] fromView:nil];
+  NSRect dirtyTitlebarRect = NSIntersectionRect(titlebarRect, dirtyRect);
+
+  LayoutDeviceIntSize texSize = TextureSizeForSize(mTitlebarRect.Size());
+  if (!mTitlebarCGContext ||
+      CGBitmapContextGetWidth(mTitlebarCGContext) != size_t(texSize.width) ||
+      CGBitmapContextGetHeight(mTitlebarCGContext) != size_t(texSize.height)) {
+    dirtyTitlebarRect = titlebarRect;
+
+    ReleaseTitlebarCGContext();
+
+    mTitlebarCGContext = CreateCGContext(texSize);
+  }
+
+  if (NSIsEmptyRect(dirtyTitlebarRect)) {
+    return;
+  }
+
+  CGContextRef ctx = mTitlebarCGContext;
+
+  CGContextSaveGState(ctx);
+
+  double scale = BackingScaleFactor();
+  CGContextScaleCTM(ctx, scale, scale);
+
+  CGContextClipToRect(ctx, NSRectToCGRect(dirtyTitlebarRect));
+  CGContextClearRect(ctx, NSRectToCGRect(dirtyTitlebarRect));
+
+  NSGraphicsContext* oldContext = [NSGraphicsContext currentContext];
+
+  CGContextSaveGState(ctx);
+
+  BaseWindow* window = (BaseWindow*)[mView window];
+  NSView* frameView = [[window contentView] superview];
+  if (![frameView isFlipped]) {
+    CGContextTranslateCTM(ctx, 0, [frameView bounds].size.height);
+    CGContextScaleCTM(ctx, 1, -1);
+  }
+  NSGraphicsContext* context = [NSGraphicsContext graphicsContextWithGraphicsPort:ctx flipped:[frameView isFlipped]];
+  [NSGraphicsContext setCurrentContext:context];
+
+  // Draw the title string.
+  if ([window wantsTitleDrawn] && [frameView respondsToSelector:@selector(_drawTitleBar:)]) {
+    [frameView _drawTitleBar:[frameView bounds]];
+  }
+
+  // Draw the titlebar controls into the titlebar image.
+  for (id view in [window titlebarControls]) {
+    NSRect viewFrame = [view frame];
+    NSRect viewRect = [mView convertRect:viewFrame fromView:frameView];
+    if (!NSIntersectsRect(dirtyTitlebarRect, viewRect)) {
+      continue;
+    }
+    // All of the titlebar controls we're interested in are subclasses of
+    // NSButton.
+    if (![view isKindOfClass:[NSButton class]]) {
+      continue;
+    }
+    NSButton *button = (NSButton *) view;
+    id cellObject = [button cell];
+    if (![cellObject isKindOfClass:[NSCell class]]) {
+      continue;
+    }
+    NSCell *cell = (NSCell *) cellObject;
+
+    CGContextSaveGState(ctx);
+    CGContextTranslateCTM(ctx, viewFrame.origin.x, viewFrame.origin.y);
+
+    if ([context isFlipped] != [view isFlipped]) {
+      CGContextTranslateCTM(ctx, 0, viewFrame.size.height);
+      CGContextScaleCTM(ctx, 1, -1);
+    }
+
+    [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:ctx flipped:[view isFlipped]]];
+
+    if ([window useBrightTitlebarForeground] && !nsCocoaFeatures::OnYosemiteOrLater() &&
+        view == [window standardWindowButton:NSWindowFullScreenButton]) {
+      // Make the fullscreen button visible on dark titlebar backgrounds by
+      // drawing it into a new transparency layer and turning it white.
+      CGRect r = NSRectToCGRect([view bounds]);
+      CGContextBeginTransparencyLayerWithRect(ctx, r, nullptr);
+
+      // Draw twice for double opacity.
+      [cell drawWithFrame:[button bounds] inView:button];
+      [cell drawWithFrame:[button bounds] inView:button];
+
+      // Make it white.
+      CGContextSetBlendMode(ctx, kCGBlendModeSourceIn);
+      CGContextSetRGBFillColor(ctx, 1, 1, 1, 1);
+      CGContextFillRect(ctx, r);
+      CGContextSetBlendMode(ctx, kCGBlendModeNormal);
+
+      CGContextEndTransparencyLayer(ctx);
+    } else {
+      [cell drawWithFrame:[button bounds] inView:button];
+    }
+
+    [NSGraphicsContext setCurrentContext:context];
+    CGContextRestoreGState(ctx);
+  }
+
+  CGContextRestoreGState(ctx);
+
+  DrawTitlebarHighlight([frameView bounds].size, [(ChildView*)mView cornerRadius],
+                        DevPixelsToCocoaPoints(1));
+
+  [NSGraphicsContext setCurrentContext:oldContext];
+
+  CGContextRestoreGState(ctx);
+
+  mUpdatedTitlebarRegion.OrWith(CocoaPointsToDevPixels(dirtyTitlebarRect));
+}
+
+// This method draws an overlay in the top of the window which contains the
+// titlebar controls (e.g. close, min, zoom, fullscreen) and the titlebar
+// highlight effect.
+// This is necessary because the real titlebar controls are covered by our
+// OpenGL context. Note that in terms of the NSView hierarchy, our ChildView
+// is actually below the titlebar controls - that's why hovering and clicking
+// them works as expected - but their visual representation is only drawn into
+// the normal window buffer, and the window buffer surface lies below the
+// GLContext surface. In order to make the titlebar controls visible, we have
+// to redraw them inside the OpenGL context surface.
+void
+nsChildView::MaybeDrawTitlebar(GLManager* aManager)
+{
+  MutexAutoLock lock(mEffectsLock);
+  if (!mIsCoveringTitlebar || mIsFullscreen) {
+    return;
+  }
+
+  LayoutDeviceIntRegion updatedTitlebarRegion;
+  updatedTitlebarRegion.And(mUpdatedTitlebarRegion, mTitlebarRect);
+  mUpdatedTitlebarRegion.SetEmpty();
+
+  if (!mTitlebarImage) {
+    mTitlebarImage = MakeUnique<RectTextureImage>();
+  }
+
+  mTitlebarImage->UpdateFromCGContext(mTitlebarRect.Size(),
+                                      updatedTitlebarRegion,
+                                      mTitlebarCGContext);
+
+  mTitlebarImage->Draw(aManager, mTitlebarRect.TopLeft());
+}
+
+static void
+DrawTopLeftCornerMask(CGContextRef aCtx, int aRadius)
+{
+  CGContextSetRGBFillColor(aCtx, 1.0, 1.0, 1.0, 1.0);
+  CGContextFillEllipseInRect(aCtx, CGRectMake(0, 0, aRadius * 2, aRadius * 2));
+}
+
+void
+nsChildView::MaybeDrawRoundedCorners(GLManager* aManager,
+                                     const LayoutDeviceIntRect& aRect)
+{
+  MutexAutoLock lock(mEffectsLock);
+
+  if (!mCornerMaskImage) {
+    mCornerMaskImage = MakeUnique<RectTextureImage>();
+  }
+
+  LayoutDeviceIntSize size(mDevPixelCornerRadius, mDevPixelCornerRadius);
+  mCornerMaskImage->UpdateIfNeeded(size, LayoutDeviceIntRegion(), ^(gfx::DrawTarget* drawTarget, const LayoutDeviceIntRegion& updateRegion) {
+    ClearRegion(drawTarget, updateRegion);
+    RefPtr<gfx::PathBuilder> builder = drawTarget->CreatePathBuilder();
+    builder->Arc(gfx::Point(mDevPixelCornerRadius, mDevPixelCornerRadius), mDevPixelCornerRadius, 0, 2.0f * M_PI);
+    RefPtr<gfx::Path> path = builder->Finish();
+    drawTarget->Fill(path,
+                     gfx::ColorPattern(gfx::Color(1.0, 1.0, 1.0, 1.0)),
+                     gfx::DrawOptions(1.0f, gfx::CompositionOp::OP_SOURCE));
+  });
+
+  // Use operator destination in: multiply all 4 channels with source alpha.
+  aManager->gl()->fBlendFuncSeparate(LOCAL_GL_ZERO, LOCAL_GL_SRC_ALPHA,
+                                     LOCAL_GL_ZERO, LOCAL_GL_SRC_ALPHA);
+
+  Matrix4x4 flipX = Matrix4x4::Scaling(-1, 1, 1);
+  Matrix4x4 flipY = Matrix4x4::Scaling(1, -1, 1);
+
+  if (mIsCoveringTitlebar && !mIsFullscreen) {
+    // Mask the top corners.
+    mCornerMaskImage->Draw(aManager, aRect.TopLeft());
+    mCornerMaskImage->Draw(aManager, aRect.TopRight(), flipX);
+  }
+
+  if (mHasRoundedBottomCorners && !mIsFullscreen) {
+    // Mask the bottom corners.
+    mCornerMaskImage->Draw(aManager, aRect.BottomLeft(), flipY);
+    mCornerMaskImage->Draw(aManager, aRect.BottomRight(), flipY * flipX);
+  }
+
+  // Reset blend mode.
+  aManager->gl()->fBlendFuncSeparate(LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA,
+                                     LOCAL_GL_ONE, LOCAL_GL_ONE);
+}
+
+static int32_t
+FindTitlebarBottom(const nsTArray<nsIWidget::ThemeGeometry>& aThemeGeometries,
+                   int32_t aWindowWidth)
+{
+  int32_t titlebarBottom = 0;
+  for (uint32_t i = 0; i < aThemeGeometries.Length(); ++i) {
+    const nsIWidget::ThemeGeometry& g = aThemeGeometries[i];
+    if ((g.mType == nsNativeThemeCocoa::eThemeGeometryTypeTitlebar) &&
+        g.mRect.X() <= 0 &&
+        g.mRect.XMost() >= aWindowWidth &&
+        g.mRect.Y() <= 0) {
+      titlebarBottom = std::max(titlebarBottom, g.mRect.YMost());
+    }
+  }
+  return titlebarBottom;
+}
+
+static int32_t
+FindUnifiedToolbarBottom(const nsTArray<nsIWidget::ThemeGeometry>& aThemeGeometries,
+                         int32_t aWindowWidth, int32_t aTitlebarBottom)
+{
+  int32_t unifiedToolbarBottom = aTitlebarBottom;
+  for (uint32_t i = 0; i < aThemeGeometries.Length(); ++i) {
+    const nsIWidget::ThemeGeometry& g = aThemeGeometries[i];
+    if ((g.mType == nsNativeThemeCocoa::eThemeGeometryTypeToolbar) &&
+        g.mRect.X() <= 0 &&
+        g.mRect.XMost() >= aWindowWidth &&
+        g.mRect.Y() <= aTitlebarBottom) {
+      unifiedToolbarBottom = std::max(unifiedToolbarBottom, g.mRect.YMost());
+    }
+  }
+  return unifiedToolbarBottom;
+}
+
+static LayoutDeviceIntRect
+FindFirstRectOfType(const nsTArray<nsIWidget::ThemeGeometry>& aThemeGeometries,
+                    nsITheme::ThemeGeometryType aThemeGeometryType)
+{
+  for (uint32_t i = 0; i < aThemeGeometries.Length(); ++i) {
+    const nsIWidget::ThemeGeometry& g = aThemeGeometries[i];
+    if (g.mType == aThemeGeometryType) {
+      return g.mRect;
+    }
+  }
+  return LayoutDeviceIntRect();
+}
+
+void
+nsChildView::UpdateThemeGeometries(const nsTArray<ThemeGeometry>& aThemeGeometries)
+{
+  if (![mView window])
+    return;
+
+  UpdateVibrancy(aThemeGeometries);
+
+  if (![[mView window] isKindOfClass:[ToolbarWindow class]])
+    return;
+
+  // Update unified toolbar height and sheet attachment position.
+  int32_t windowWidth = mBounds.width;
+  int32_t titlebarBottom = FindTitlebarBottom(aThemeGeometries, windowWidth);
+  int32_t unifiedToolbarBottom =
+    FindUnifiedToolbarBottom(aThemeGeometries, windowWidth, titlebarBottom);
+  int32_t toolboxBottom =
+    FindFirstRectOfType(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeToolbox).YMost();
+
+  ToolbarWindow* win = (ToolbarWindow*)[mView window];
+  bool drawsContentsIntoWindowFrame = [win drawsContentsIntoWindowFrame];
+  int32_t titlebarHeight = CocoaPointsToDevPixels([win titlebarHeight]);
+  int32_t contentOffset = drawsContentsIntoWindowFrame ? titlebarHeight : 0;
+  int32_t devUnifiedHeight = titlebarHeight + unifiedToolbarBottom - contentOffset;
+  [win setUnifiedToolbarHeight:DevPixelsToCocoaPoints(devUnifiedHeight)];
+  int32_t devSheetPosition = titlebarHeight + std::max(toolboxBottom, unifiedToolbarBottom) - contentOffset;
+  [win setSheetAttachmentPosition:DevPixelsToCocoaPoints(devSheetPosition)];
+
+  // Update titlebar control offsets.
+  LayoutDeviceIntRect windowButtonRect = FindFirstRectOfType(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeWindowButtons);
+  [win placeWindowButtons:[mView convertRect:DevPixelsToCocoaPoints(windowButtonRect) toView:nil]];
+  LayoutDeviceIntRect fullScreenButtonRect = FindFirstRectOfType(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeFullscreenButton);
+  [win placeFullScreenButton:[mView convertRect:DevPixelsToCocoaPoints(fullScreenButtonRect) toView:nil]];
+}
+
+static LayoutDeviceIntRegion
+GatherThemeGeometryRegion(const nsTArray<nsIWidget::ThemeGeometry>& aThemeGeometries,
+                          nsITheme::ThemeGeometryType aThemeGeometryType)
+{
+  LayoutDeviceIntRegion region;
+  for (size_t i = 0; i < aThemeGeometries.Length(); ++i) {
+    const nsIWidget::ThemeGeometry& g = aThemeGeometries[i];
+    if (g.mType == aThemeGeometryType) {
+      region.OrWith(g.mRect);
+    }
+  }
+  return region;
+}
+
+template<typename Region>
+static void MakeRegionsNonOverlappingImpl(Region& aOutUnion) { }
+
+template<typename Region, typename ... Regions>
+static void MakeRegionsNonOverlappingImpl(Region& aOutUnion, Region& aFirst, Regions& ... aRest)
+{
+  MakeRegionsNonOverlappingImpl(aOutUnion, aRest...);
+  aFirst.SubOut(aOutUnion);
+  aOutUnion.OrWith(aFirst);
+}
+
+// Subtracts parts from regions in such a way that they don't have any overlap.
+// Each region in the argument list will have the union of all the regions
+// *following* it subtracted from itself. In other words, the arguments are
+// sorted low priority to high priority.
+template<typename Region, typename ... Regions>
+static void MakeRegionsNonOverlapping(Region& aFirst, Regions& ... aRest)
+{
+  Region unionOfAll;
+  MakeRegionsNonOverlappingImpl(unionOfAll, aFirst, aRest...);
+}
+
+void
+nsChildView::UpdateVibrancy(const nsTArray<ThemeGeometry>& aThemeGeometries)
+{
+  if (!VibrancyManager::SystemSupportsVibrancy()) {
+    return;
+  }
+
+  LayoutDeviceIntRegion sheetRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeSheet);
+  LayoutDeviceIntRegion vibrantLightRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeVibrancyLight);
+  LayoutDeviceIntRegion vibrantDarkRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeVibrancyDark);
+  LayoutDeviceIntRegion menuRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeMenu);
+  LayoutDeviceIntRegion tooltipRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeTooltip);
+  LayoutDeviceIntRegion highlightedMenuItemRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeHighlightedMenuItem);
+  LayoutDeviceIntRegion sourceListRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeSourceList);
+  LayoutDeviceIntRegion sourceListSelectionRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeSourceListSelection);
+  LayoutDeviceIntRegion activeSourceListSelectionRegion =
+    GatherThemeGeometryRegion(aThemeGeometries, nsNativeThemeCocoa::eThemeGeometryTypeActiveSourceListSelection);
+
+  MakeRegionsNonOverlapping(sheetRegion, vibrantLightRegion, vibrantDarkRegion,
+                            menuRegion, tooltipRegion, highlightedMenuItemRegion,
+                            sourceListRegion, sourceListSelectionRegion,
+                            activeSourceListSelectionRegion);
+
+  auto& vm = EnsureVibrancyManager();
+  vm.UpdateVibrantRegion(VibrancyType::LIGHT, vibrantLightRegion);
+  vm.UpdateVibrantRegion(VibrancyType::TOOLTIP, tooltipRegion);
+  vm.UpdateVibrantRegion(VibrancyType::MENU, menuRegion);
+  vm.UpdateVibrantRegion(VibrancyType::HIGHLIGHTED_MENUITEM, highlightedMenuItemRegion);
+  vm.UpdateVibrantRegion(VibrancyType::SHEET, sheetRegion);
+  vm.UpdateVibrantRegion(VibrancyType::SOURCE_LIST, sourceListRegion);
+  vm.UpdateVibrantRegion(VibrancyType::SOURCE_LIST_SELECTION, sourceListSelectionRegion);
+  vm.UpdateVibrantRegion(VibrancyType::ACTIVE_SOURCE_LIST_SELECTION, activeSourceListSelectionRegion);
+  vm.UpdateVibrantRegion(VibrancyType::DARK, vibrantDarkRegion);
+}
+
+static VibrancyType
+ThemeGeometryTypeToVibrancyType(nsITheme::ThemeGeometryType aThemeGeometryType)
+{
+  switch (aThemeGeometryType) {
+    case nsNativeThemeCocoa::eThemeGeometryTypeVibrancyLight:
+      return VibrancyType::LIGHT;
+    case nsNativeThemeCocoa::eThemeGeometryTypeVibrancyDark:
+      return VibrancyType::DARK;
+    case nsNativeThemeCocoa::eThemeGeometryTypeTooltip:
+      return VibrancyType::TOOLTIP;
+    case nsNativeThemeCocoa::eThemeGeometryTypeMenu:
+      return VibrancyType::MENU;
+    case nsNativeThemeCocoa::eThemeGeometryTypeHighlightedMenuItem:
+      return VibrancyType::HIGHLIGHTED_MENUITEM;
+    case nsNativeThemeCocoa::eThemeGeometryTypeSheet:
+      return VibrancyType::SHEET;
+    case nsNativeThemeCocoa::eThemeGeometryTypeSourceList:
+      return VibrancyType::SOURCE_LIST;
+    case nsNativeThemeCocoa::eThemeGeometryTypeSourceListSelection:
+      return VibrancyType::SOURCE_LIST_SELECTION;
+    case nsNativeThemeCocoa::eThemeGeometryTypeActiveSourceListSelection:
+      return VibrancyType::ACTIVE_SOURCE_LIST_SELECTION;
+    default:
+      MOZ_CRASH();
+  }
+}
+
+NSColor*
+nsChildView::VibrancyFillColorForThemeGeometryType(nsITheme::ThemeGeometryType aThemeGeometryType)
+{
+  if (VibrancyManager::SystemSupportsVibrancy()) {
+    return EnsureVibrancyManager().VibrancyFillColorForType(
+      ThemeGeometryTypeToVibrancyType(aThemeGeometryType));
+  }
+  return [NSColor whiteColor];
+}
+
+NSColor*
+nsChildView::VibrancyFontSmoothingBackgroundColorForThemeGeometryType(nsITheme::ThemeGeometryType aThemeGeometryType)
+{
+  if (VibrancyManager::SystemSupportsVibrancy()) {
+    return EnsureVibrancyManager().VibrancyFontSmoothingBackgroundColorForType(
+      ThemeGeometryTypeToVibrancyType(aThemeGeometryType));
+  }
+  return [NSColor clearColor];
+}
+
+mozilla::VibrancyManager&
+nsChildView::EnsureVibrancyManager()
+{
+  MOZ_ASSERT(mView, "Only call this once we have a view!");
+  if (!mVibrancyManager) {
+    mVibrancyManager = MakeUnique<VibrancyManager>(*this, [mView vibrancyViewsContainer]);
+  }
+  return *mVibrancyManager;
+}
+
+nsChildView::SwipeInfo
+nsChildView::SendMayStartSwipe(const mozilla::PanGestureInput& aSwipeStartEvent)
+{
+  nsCOMPtr<nsIWidget> kungFuDeathGrip(this);
+
+  uint32_t direction = (aSwipeStartEvent.mPanDisplacement.x > 0.0)
+    ? (uint32_t)nsIDOMSimpleGestureEvent::DIRECTION_RIGHT
+    : (uint32_t)nsIDOMSimpleGestureEvent::DIRECTION_LEFT;
+
+  // We're ready to start the animation. Tell Gecko about it, and at the same
+  // time ask it if it really wants to start an animation for this event.
+  // This event also reports back the directions that we can swipe in.
+  LayoutDeviceIntPoint position =
+    RoundedToInt(aSwipeStartEvent.mPanStartPoint * ScreenToLayoutDeviceScale(1));
+  WidgetSimpleGestureEvent geckoEvent =
+    SwipeTracker::CreateSwipeGestureEvent(eSwipeGestureMayStart, this,
+                                          position);
+  geckoEvent.mDirection = direction;
+  geckoEvent.mDelta = 0.0;
+  geckoEvent.mAllowedDirections = 0;
+  bool shouldStartSwipe = DispatchWindowEvent(geckoEvent); // event cancelled == swipe should start
+
+  SwipeInfo result = { shouldStartSwipe, geckoEvent.mAllowedDirections };
+  return result;
+}
+
+void
+nsChildView::TrackScrollEventAsSwipe(const mozilla::PanGestureInput& aSwipeStartEvent,
+                                     uint32_t aAllowedDirections)
+{
+  // If a swipe is currently being tracked kill it -- it's been interrupted
+  // by another gesture event.
+  if (mSwipeTracker) {
+    mSwipeTracker->CancelSwipe();
+    mSwipeTracker->Destroy();
+    mSwipeTracker = nullptr;
+  }
+
+  uint32_t direction = (aSwipeStartEvent.mPanDisplacement.x > 0.0)
+    ? (uint32_t)nsIDOMSimpleGestureEvent::DIRECTION_RIGHT
+    : (uint32_t)nsIDOMSimpleGestureEvent::DIRECTION_LEFT;
+
+  mSwipeTracker = new SwipeTracker(*this, aSwipeStartEvent,
+                                   aAllowedDirections, direction);
+
+  if (!mAPZC) {
+    mCurrentPanGestureBelongsToSwipe = true;
+  }
+}
+
+void
+nsChildView::SwipeFinished()
+{
+  mSwipeTracker = nullptr;
+}
+
+already_AddRefed<gfx::DrawTarget>
+nsChildView::StartRemoteDrawingInRegion(LayoutDeviceIntRegion& aInvalidRegion,
+                                        BufferMode* aBufferMode)
+{
+  // should have created the GLPresenter in InitCompositor.
+  MOZ_ASSERT(mGLPresenter);
+  if (!mGLPresenter) {
+    mGLPresenter = GLPresenter::CreateForWindow(this);
+
+    if (!mGLPresenter) {
+      return nullptr;
+    }
+  }
+
+  LayoutDeviceIntRegion dirtyRegion(aInvalidRegion);
+  LayoutDeviceIntSize renderSize = mBounds.Size();
+
+  if (!mBasicCompositorImage) {
+    mBasicCompositorImage = MakeUnique<RectTextureImage>();
+  }
+
+  RefPtr<gfx::DrawTarget> drawTarget =
+    mBasicCompositorImage->BeginUpdate(renderSize, dirtyRegion);
+
+  if (!drawTarget) {
+    // Composite unchanged textures.
+    DoRemoteComposition(mBounds);
+    return nullptr;
+  }
+
+  aInvalidRegion = mBasicCompositorImage->GetUpdateRegion();
+  *aBufferMode = BufferMode::BUFFER_NONE;
+
+  return drawTarget.forget();
+}
+
+void
+nsChildView::EndRemoteDrawing()
+{
+  mBasicCompositorImage->EndUpdate();
+  DoRemoteComposition(mBounds);
+}
+
+void
+nsChildView::CleanupRemoteDrawing()
+{
+  mBasicCompositorImage = nullptr;
+  mCornerMaskImage = nullptr;
+  mResizerImage = nullptr;
+  mTitlebarImage = nullptr;
+  mGLPresenter = nullptr;
+}
+
+bool
+nsChildView::InitCompositor(Compositor* aCompositor)
+{
+  if (aCompositor->GetBackendType() == LayersBackend::LAYERS_BASIC) {
+    if (!mGLPresenter) {
+      mGLPresenter = GLPresenter::CreateForWindow(this);
+    }
+
+    return !!mGLPresenter;
+  }
+  return true;
+}
+
+void
+nsChildView::DoRemoteComposition(const LayoutDeviceIntRect& aRenderRect)
+{
+  if (![(ChildView*)mView preRender:mGLPresenter->GetNSOpenGLContext()]) {
+    return;
+  }
+  mGLPresenter->BeginFrame(aRenderRect.Size());
+
+  // Draw the result from the basic compositor.
+  mBasicCompositorImage->Draw(mGLPresenter.get(), LayoutDeviceIntPoint(0, 0));
+
+  // DrawWindowOverlay doesn't do anything for non-GL, so it didn't paint
+  // anything during the basic compositor transaction. Draw the overlay now.
+  DrawWindowOverlay(mGLPresenter.get(), aRenderRect);
+
+  mGLPresenter->EndFrame();
+
+  [(ChildView*)mView postRender:mGLPresenter->GetNSOpenGLContext()];
+}
+
+@interface NonDraggableView : NSView
+@end
+
+@implementation NonDraggableView
+- (BOOL)mouseDownCanMoveWindow { return NO; }
+- (NSView*)hitTest:(NSPoint)aPoint { return nil; }
+@end
+
+void
+nsChildView::UpdateWindowDraggingRegion(const LayoutDeviceIntRegion& aRegion)
+{
+  // mView returns YES from mouseDownCanMoveWindow, so we need to put NSViews
+  // that return NO from mouseDownCanMoveWindow in the places that shouldn't
+  // be draggable. We can't do it the other way round because returning
+  // YES from mouseDownCanMoveWindow doesn't have any effect if there's a
+  // superview that returns NO.
+  LayoutDeviceIntRegion nonDraggable;
+  nonDraggable.Sub(LayoutDeviceIntRect(0, 0, mBounds.width, mBounds.height), aRegion);
+
+  __block bool changed = false;
+
+  // Suppress calls to setNeedsDisplay during NSView geometry changes.
+  ManipulateViewWithoutNeedingDisplay(mView, ^() {
+    changed = mNonDraggableRegion.UpdateRegion(
+        nonDraggable, *this, [mView nonDraggableViewsContainer], ^() {
+          return [[NonDraggableView alloc] initWithFrame:NSZeroRect];
+        });
+  });
+
+  if (changed) {
+    // Trigger an update to the window server. This will call
+    // mouseDownCanMoveWindow.
+    // Doing this manually is only necessary because we're suppressing
+    // setNeedsDisplay calls above.
+    [[mView window] setMovableByWindowBackground:NO];
+    [[mView window] setMovableByWindowBackground:YES];
+  }
+}
+
+void
+nsChildView::ReportSwipeStarted(uint64_t aInputBlockId,
+                                bool aStartSwipe)
+{
+  if (mSwipeEventQueue && mSwipeEventQueue->inputBlockId == aInputBlockId) {
+    if (aStartSwipe) {
+      PanGestureInput& startEvent = mSwipeEventQueue->queuedEvents[0];
+      TrackScrollEventAsSwipe(startEvent, mSwipeEventQueue->allowedDirections);
+      for (size_t i = 1; i < mSwipeEventQueue->queuedEvents.Length(); i++) {
+        mSwipeTracker->ProcessEvent(mSwipeEventQueue->queuedEvents[i]);
+      }
+    }
+    mSwipeEventQueue = nullptr;
+  }
+}
+
+void
+nsChildView::DispatchAPZWheelInputEvent(InputData& aEvent, bool aCanTriggerSwipe)
+{
+  if (mSwipeTracker && aEvent.mInputType == PANGESTURE_INPUT) {
+    // Give the swipe tracker a first pass at the event. If a new pan gesture
+    // has been started since the beginning of the swipe, the swipe tracker
+    // will know to ignore the event.
+    nsEventStatus status = mSwipeTracker->ProcessEvent(aEvent.AsPanGestureInput());
+    if (status == nsEventStatus_eConsumeNoDefault) {
+      return;
+    }
+  }
+
+  WidgetWheelEvent event(true, eWheel, this);
+
+  if (mAPZC) {
+    uint64_t inputBlockId = 0;
+    ScrollableLayerGuid guid;
+
+    nsEventStatus result = mAPZC->ReceiveInputEvent(aEvent, &guid, &inputBlockId);
+    if (result == nsEventStatus_eConsumeNoDefault) {
+      return;
+    }
+
+    switch(aEvent.mInputType) {
+      case PANGESTURE_INPUT: {
+        PanGestureInput& panInput = aEvent.AsPanGestureInput();
+
+        event = panInput.ToWidgetWheelEvent(this);
+        if (aCanTriggerSwipe) {
+          SwipeInfo swipeInfo = SendMayStartSwipe(panInput);
+          event.mCanTriggerSwipe = swipeInfo.wantsSwipe;
+          if (swipeInfo.wantsSwipe) {
+            if (result == nsEventStatus_eIgnore) {
+              // APZ has determined and that scrolling horizontally in the
+              // requested direction is impossible, so it didn't do any
+              // scrolling for the event.
+              // We know now that MayStartSwipe wants a swipe, so we can start
+              // the swipe now.
+              TrackScrollEventAsSwipe(panInput, swipeInfo.allowedDirections);
+            } else {
+              // We don't know whether this event can start a swipe, so we need
+              // to queue up events and wait for a call to ReportSwipeStarted.
+              // APZ might already have started scrolling in response to the
+              // event if it knew that it's the right thing to do. In that case
+              // we'll still get a call to ReportSwipeStarted, and we will
+              // discard the queued events at that point.
+              mSwipeEventQueue = MakeUnique<SwipeEventQueue>(swipeInfo.allowedDirections,
+                                                             inputBlockId);
+            }
+          }
+        }
+
+        if (mSwipeEventQueue && mSwipeEventQueue->inputBlockId == inputBlockId) {
+          mSwipeEventQueue->queuedEvents.AppendElement(panInput);
+        }
+        break;
+      }
+      case SCROLLWHEEL_INPUT: {
+        event = aEvent.AsScrollWheelInput().ToWidgetWheelEvent(this);
+        break;
+      };
+      default:
+        MOZ_CRASH("unsupported event type");
+        return;
+    }
+    if (event.mMessage == eWheel &&
+        (event.mDeltaX != 0 || event.mDeltaY != 0)) {
+      ProcessUntransformedAPZEvent(&event, guid, inputBlockId, result);
+    }
+    return;
+  }
+
+  nsEventStatus status;
+  switch(aEvent.mInputType) {
+    case PANGESTURE_INPUT: {
+      PanGestureInput panInput = aEvent.AsPanGestureInput();
+      if (panInput.mType == PanGestureInput::PANGESTURE_MAYSTART ||
+          panInput.mType == PanGestureInput::PANGESTURE_START) {
+        mCurrentPanGestureBelongsToSwipe = false;
+      }
+      if (mCurrentPanGestureBelongsToSwipe) {
+        // Ignore this event. It's a momentum event from a scroll gesture
+        // that was processed as a swipe, and the swipe animation has
+        // already finished (so mSwipeTracker is already null).
+        MOZ_ASSERT(panInput.IsMomentum(),
+          "If the fingers are still on the touchpad, we should still have a SwipeTracker, and it should have consumed this event.");
+        return;
+      }
+
+      event = panInput.ToWidgetWheelEvent(this);
+      if (aCanTriggerSwipe) {
+        SwipeInfo swipeInfo = SendMayStartSwipe(panInput);
+
+        // We're in the non-APZ case here, but we still want to know whether
+        // the event was routed to a child process, so we use InputAPZContext
+        // to get that piece of information.
+        ScrollableLayerGuid guid;
+        InputAPZContext context(guid, 0, nsEventStatus_eIgnore);
+
+        event.mCanTriggerSwipe = swipeInfo.wantsSwipe;
+        DispatchEvent(&event, status);
+        if (swipeInfo.wantsSwipe) {
+          if (context.WasRoutedToChildProcess()) {
+            // We don't know whether this event can start a swipe, so we need
+            // to queue up events and wait for a call to ReportSwipeStarted.
+            mSwipeEventQueue = MakeUnique<SwipeEventQueue>(swipeInfo.allowedDirections, 0);
+          } else if (event.TriggersSwipe()) {
+            TrackScrollEventAsSwipe(panInput, swipeInfo.allowedDirections);
+          }
+        }
+
+        if (mSwipeEventQueue && mSwipeEventQueue->inputBlockId == 0) {
+          mSwipeEventQueue->queuedEvents.AppendElement(panInput);
+        }
+        return;
+      }
+      break;
+    }
+    case SCROLLWHEEL_INPUT: {
+      event = aEvent.AsScrollWheelInput().ToWidgetWheelEvent(this);
+      break;
+    }
+    default:
+      MOZ_CRASH("unexpected event type");
+      return;
+  }
+  if (event.mMessage == eWheel &&
+      (event.mDeltaX != 0 || event.mDeltaY != 0)) {
+    DispatchEvent(&event, status);
+  }
+}
+
+// When using 10.11, calling showDefinitionForAttributedString causes the
+// following exception on LookupViewService. (rdar://26476091)
+//
+// Exception: decodeObjectForKey: class "TitlebarAndBackgroundColor" not
+// loaded or does not exist
+//
+// So we set temporary color that is NSColor before calling it.
+
+class MOZ_RAII AutoBackgroundSetter final {
+public:
+  explicit AutoBackgroundSetter(NSView* aView) {
+    if (nsCocoaFeatures::OnElCapitanOrLater() &&
+        [[aView window] isKindOfClass:[ToolbarWindow class]]) {
+      mWindow = [(ToolbarWindow*)[aView window] retain];
+      [mWindow setTemporaryBackgroundColor];
+    } else {
+      mWindow = nullptr;
+    }
+  }
+
+  ~AutoBackgroundSetter() {
+    if (mWindow) {
+      [mWindow restoreBackgroundColor];
+      [mWindow release];
+    }
+  }
+
+private:
+  ToolbarWindow* mWindow; // strong
+};
+
+void
+nsChildView::LookUpDictionary(
+               const nsAString& aText,
+               const nsTArray<mozilla::FontRange>& aFontRangeArray,
+               const bool aIsVertical,
+               const LayoutDeviceIntPoint& aPoint)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NSMutableAttributedString* attrStr =
+    nsCocoaUtils::GetNSMutableAttributedString(aText, aFontRangeArray,
+                                               aIsVertical,
+                                               BackingScaleFactor());
+  NSPoint pt =
+    nsCocoaUtils::DevPixelsToCocoaPoints(aPoint, BackingScaleFactor());
+  NSDictionary* attributes = [attrStr attributesAtIndex:0 effectiveRange:nil];
+  NSFont* font = [attributes objectForKey:NSFontAttributeName];
+  if (font) {
+    if (aIsVertical) {
+      pt.x -= [font descender];
+    } else {
+      pt.y += [font ascender];
+    }
+  }
+
+  AutoBackgroundSetter setter(mView);
+  [mView showDefinitionForAttributedString:attrStr atPoint:pt];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+#ifdef ACCESSIBILITY
+already_AddRefed<a11y::Accessible>
+nsChildView::GetDocumentAccessible()
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return nullptr;
+
+  if (mAccessible) {
+    RefPtr<a11y::Accessible> ret;
+    CallQueryReferent(mAccessible.get(),
+                      static_cast<a11y::Accessible**>(getter_AddRefs(ret)));
+    return ret.forget();
+  }
+
+  // need to fetch the accessible anew, because it has gone away.
+  // cache the accessible in our weak ptr
+  RefPtr<a11y::Accessible> acc = GetRootAccessible();
+  mAccessible = do_GetWeakReference(acc.get());
+
+  return acc.forget();
+}
+#endif
+
+// GLPresenter implementation
+
+GLPresenter::GLPresenter(GLContext* aContext)
+ : mGLContext(aContext)
+{
+  mGLContext->MakeCurrent();
+  ShaderConfigOGL config;
+  config.SetTextureTarget(LOCAL_GL_TEXTURE_RECTANGLE_ARB);
+  mRGBARectProgram = MakeUnique<ShaderProgramOGL>(mGLContext,
+    ProgramProfileOGL::GetProfileFor(config));
+
+  // Create mQuadVBO.
+  mGLContext->fGenBuffers(1, &mQuadVBO);
+  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, mQuadVBO);
+
+  // 1 quad, with the number of the quad (vertexID) encoded in w.
+  GLfloat vertices[] = {
+    0.0f, 0.0f, 0.0f, 0.0f,
+    1.0f, 0.0f, 0.0f, 0.0f,
+    0.0f, 1.0f, 0.0f, 0.0f,
+    1.0f, 0.0f, 0.0f, 0.0f,
+    0.0f, 1.0f, 0.0f, 0.0f,
+    1.0f, 1.0f, 0.0f, 0.0f,
+  };
+  HeapCopyOfStackArray<GLfloat> verticesOnHeap(vertices);
+  mGLContext->fBufferData(LOCAL_GL_ARRAY_BUFFER,
+                          verticesOnHeap.ByteLength(),
+                          verticesOnHeap.Data(),
+                          LOCAL_GL_STATIC_DRAW);
+   mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);
+}
+
+GLPresenter::~GLPresenter()
+{
+  if (mQuadVBO) {
+    mGLContext->MakeCurrent();
+    mGLContext->fDeleteBuffers(1, &mQuadVBO);
+    mQuadVBO = 0;
+  }
+}
+
+void
+GLPresenter::BindAndDrawQuad(ShaderProgramOGL *aProgram,
+                             const gfx::Rect& aLayerRect,
+                             const gfx::Rect& aTextureRect)
+{
+  mGLContext->MakeCurrent();
+
+  gfx::Rect layerRects[4];
+  gfx::Rect textureRects[4];
+
+  layerRects[0] = aLayerRect;
+  textureRects[0] = aTextureRect;
+
+  aProgram->SetLayerRects(layerRects);
+  aProgram->SetTextureRects(textureRects);
+
+  const GLuint coordAttribIndex = 0;
+
+  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, mQuadVBO);
+  mGLContext->fVertexAttribPointer(coordAttribIndex, 4,
+                                   LOCAL_GL_FLOAT, LOCAL_GL_FALSE, 0,
+                                   (GLvoid*)0);
+  mGLContext->fEnableVertexAttribArray(coordAttribIndex);
+  mGLContext->fDrawArrays(LOCAL_GL_TRIANGLES, 0, 6);
+  mGLContext->fDisableVertexAttribArray(coordAttribIndex);
+}
+
+void
+GLPresenter::BeginFrame(LayoutDeviceIntSize aRenderSize)
+{
+  mGLContext->MakeCurrent();
+
+  mGLContext->fViewport(0, 0, aRenderSize.width, aRenderSize.height);
+
+  // Matrix to transform (0, 0, width, height) to viewport space (-1.0, 1.0,
+  // 2, 2) and flip the contents.
+  gfx::Matrix viewMatrix = gfx::Matrix::Translation(-1.0, 1.0);
+  viewMatrix.PreScale(2.0f / float(aRenderSize.width),
+                      2.0f / float(aRenderSize.height));
+  viewMatrix.PreScale(1.0f, -1.0f);
+
+  gfx::Matrix4x4 matrix3d = gfx::Matrix4x4::From2D(viewMatrix);
+  matrix3d._33 = 0.0f;
+
+  // set the projection matrix for the next time the program is activated
+  mProjMatrix = matrix3d;
+
+  // Default blend function implements "OVER"
+  mGLContext->fBlendFuncSeparate(LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA,
+                                 LOCAL_GL_ONE, LOCAL_GL_ONE);
+  mGLContext->fEnable(LOCAL_GL_BLEND);
+
+  mGLContext->fClearColor(0.0, 0.0, 0.0, 0.0);
+  mGLContext->fClear(LOCAL_GL_COLOR_BUFFER_BIT | LOCAL_GL_DEPTH_BUFFER_BIT);
+
+  mGLContext->fEnable(LOCAL_GL_TEXTURE_RECTANGLE_ARB);
+}
+
+void
+GLPresenter::EndFrame()
+{
+  mGLContext->SwapBuffers();
+  mGLContext->fBindBuffer(LOCAL_GL_ARRAY_BUFFER, 0);
+}
+
+class WidgetsReleaserRunnable final : public mozilla::Runnable
+{
+public:
+  explicit WidgetsReleaserRunnable(nsTArray<nsCOMPtr<nsIWidget>>&& aWidgetArray)
+    : mWidgetArray(aWidgetArray)
+  {
+  }
+
+  // Do nothing; all this runnable does is hold a reference the widgets in
+  // mWidgetArray, and those references will be dropped when this runnable
+  // is destroyed.
+
+private:
+  nsTArray<nsCOMPtr<nsIWidget>> mWidgetArray;
+};
+
+#pragma mark -
+
+// ViewRegionContainerView is a view class for certain subviews of ChildView
+// which contain the NSViews created for ViewRegions (see ViewRegion.h).
+// It doesn't do anything interesting, it only acts as a container so that it's
+// easier for ChildView to control the z order of its children.
+@interface ViewRegionContainerView : NSView {
+}
+@end
+
+@implementation ViewRegionContainerView
+
+- (NSView*)hitTest:(NSPoint)aPoint {
+  return nil;  // Be transparent to mouse events.
+}
+
+- (BOOL)isFlipped {
+  return [[self superview] isFlipped];
+}
+
+- (BOOL)mouseDownCanMoveWindow {
+  return [[self superview] mouseDownCanMoveWindow];
+}
+
+@end
+;
+
+@implementation ChildView
+
+// globalDragPboard is non-null during native drag sessions that did not originate
+// in our native NSView (it is set in |draggingEntered:|). It is unset when the
+// drag session ends for this view, either with the mouse exiting or when a drop
+// occurs in this view.
+NSPasteboard* globalDragPboard = nil;
+
+// gLastDragView and gLastDragMouseDownEvent are used to communicate information
+// to the drag service during drag invocation (starting a drag in from the view).
+// gLastDragView is only non-null while mouseDragged is on the call stack.
+NSView* gLastDragView = nil;
+NSEvent* gLastDragMouseDownEvent = nil;
+
++ (void)initialize
+{
+  static BOOL initialized = NO;
+
+  if (!initialized) {
+    // Inform the OS about the types of services (from the "Services" menu)
+    // that we can handle.
+
+    NSArray *sendTypes = [[NSArray alloc] initWithObjects:NSStringPboardType,NSHTMLPboardType,nil];
+    NSArray *returnTypes = [[NSArray alloc] initWithObjects:NSStringPboardType,NSHTMLPboardType,nil];
+
+    [NSApp registerServicesMenuSendTypes:sendTypes returnTypes:returnTypes];
+
+    [sendTypes release];
+    [returnTypes release];
+
+    initialized = YES;
+  }
+}
+
++ (void)registerViewForDraggedTypes:(NSView*)aView
+{
+  [aView registerForDraggedTypes:[NSArray arrayWithObjects:NSFilenamesPboardType,
+                                                           NSStringPboardType,
+                                                           NSHTMLPboardType,
+                                                           NSURLPboardType,
+                                                           NSFilesPromisePboardType,
+                                                           kWildcardPboardType,
+                                                           kCorePboardType_url,
+                                                           kCorePboardType_urld,
+                                                           kCorePboardType_urln,
+                                                           nil]];
+}
+
+// initWithFrame:geckoChild:
+- (id)initWithFrame:(NSRect)inFrame geckoChild:(nsChildView*)inChild
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if ((self = [super initWithFrame:inFrame])) {
+    mGeckoChild = inChild;
+    mBlockedLastMouseDown = NO;
+    mExpectingWheelStop = NO;
+
+    mLastMouseDownEvent = nil;
+    mLastKeyDownEvent = nil;
+    mClickThroughMouseDownEvent = nil;
+    mDragService = nullptr;
+
+    mGestureState = eGestureState_None;
+    mCumulativeMagnification = 0.0;
+    mCumulativeRotation = 0.0;
+
+    mNeedsGLUpdate = NO;
+
+    [self setFocusRingType:NSFocusRingTypeNone];
+
+#ifdef __LP64__
+    mCancelSwipeAnimation = nil;
+#endif
+
+    mNonDraggableViewsContainer = [[ViewRegionContainerView alloc] initWithFrame:[self bounds]];
+    mVibrancyViewsContainer = [[ViewRegionContainerView alloc] initWithFrame:[self bounds]];
+
+    [mNonDraggableViewsContainer setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
+    [mVibrancyViewsContainer setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
+
+    [self addSubview:mNonDraggableViewsContainer];
+    [self addSubview:mVibrancyViewsContainer];
+
+    mPixelHostingView = [[PixelHostingView alloc] initWithFrame:[self bounds]];
+    [mPixelHostingView setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
+
+    [self addSubview:mPixelHostingView];
+
+    mTopLeftCornerMask = NULL;
+  }
+
+  // register for things we'll take from other applications
+  [ChildView registerViewForDraggedTypes:self];
+
+  [[NSNotificationCenter defaultCenter] addObserver:self
+                                           selector:@selector(systemMetricsChanged)
+                                               name:NSControlTintDidChangeNotification
+                                             object:nil];
+  [[NSNotificationCenter defaultCenter] addObserver:self
+                                           selector:@selector(systemMetricsChanged)
+                                               name:NSSystemColorsDidChangeNotification
+                                             object:nil];
+  [[NSNotificationCenter defaultCenter] addObserver:self
+                                           selector:@selector(scrollbarSystemMetricChanged)
+                                               name:NSPreferredScrollerStyleDidChangeNotification
+                                             object:nil];
+  [[NSDistributedNotificationCenter defaultCenter] addObserver:self
+                                                      selector:@selector(systemMetricsChanged)
+                                                          name:@"AppleAquaScrollBarVariantChanged"
+                                                        object:nil
+                                            suspensionBehavior:NSNotificationSuspensionBehaviorDeliverImmediately];
+  [[NSNotificationCenter defaultCenter] addObserver:self
+                                           selector:@selector(_surfaceNeedsUpdate:)
+                                               name:NSViewGlobalFrameDidChangeNotification
+                                             object:mPixelHostingView];
+
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+// ComplexTextInputPanel's interpretKeyEvent hack won't work without this.
+// It makes calls to +[NSTextInputContext currentContext], deep in system
+// code, return the appropriate context.
+- (NSTextInputContext *)inputContext
+{
+  NSTextInputContext* pluginContext = NULL;
+  if (mGeckoChild && mGeckoChild->IsPluginFocused()) {
+    ComplexTextInputPanel* ctiPanel =
+      ComplexTextInputPanel::GetSharedComplexTextInputPanel();
+    if (ctiPanel) {
+      pluginContext = (NSTextInputContext*) ctiPanel->GetInputContext();
+    }
+  }
+  if (pluginContext) {
+    return pluginContext;
+  } else {
+    if (!mGeckoChild) {
+      // -[ChildView widgetDestroyed] has been called, but
+      // -[ChildView delayedTearDown] has not yet completed.  Accessing
+      // [super inputContext] now would uselessly recreate a text input context
+      // for us, under which -[ChildView validAttributesForMarkedText] would
+      // be called and the assertion checking for mTextInputHandler would fail.
+      // We return nil to avoid that.
+      return nil;
+    }
+    return [super inputContext];
+  }
+}
+
+- (void)installTextInputHandler:(TextInputHandler*)aHandler
+{
+  mTextInputHandler = aHandler;
+}
+
+- (void)uninstallTextInputHandler
+{
+  mTextInputHandler = nullptr;
+}
+
+- (bool)preRender:(NSOpenGLContext *)aGLContext
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (![self window] ||
+      ([[self window] isKindOfClass:[BaseWindow class]] &&
+       ![(BaseWindow*)[self window] isVisibleOrBeingShown])) {
+    // Before the window is shown, our GL context's front FBO is not
+    // framebuffer complete, so we refuse to render.
+    return false;
+  }
+
+  if (!mGLContext) {
+    mGLContext = aGLContext;
+    [mGLContext retain];
+    mNeedsGLUpdate = true;
+  }
+
+  CGLLockContext((CGLContextObj)[aGLContext CGLContextObj]);
+
+  if (mNeedsGLUpdate) {
+    [self updateGLContext];
+    mNeedsGLUpdate = NO;
+  }
+
+  return true;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+- (void)postRender:(NSOpenGLContext *)aGLContext
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  CGLUnlockContext((CGLContextObj)[aGLContext CGLContextObj]);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (NSView*)vibrancyViewsContainer {
+  return mVibrancyViewsContainer;
+}
+
+- (NSView*)nonDraggableViewsContainer {
+  return mNonDraggableViewsContainer;
+}
+
+- (NSView*)pixelHostingView {
+  return mPixelHostingView;
+}
+
+- (void)dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mGLContext release];
+  [mLastMouseDownEvent release];
+  [mLastKeyDownEvent release];
+  [mClickThroughMouseDownEvent release];
+  CGImageRelease(mTopLeftCornerMask);
+  ChildViewMouseTracker::OnDestroyView(self);
+
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  [[NSDistributedNotificationCenter defaultCenter] removeObserver:self];
+  [mVibrancyViewsContainer removeFromSuperview];
+  [mVibrancyViewsContainer release];
+  [mNonDraggableViewsContainer removeFromSuperview];
+  [mNonDraggableViewsContainer release];
+  [mPixelHostingView removeFromSuperview];
+  [mPixelHostingView release];
+
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)widgetDestroyed
+{
+  if (mTextInputHandler) {
+    mTextInputHandler->OnDestroyWidget(mGeckoChild);
+    mTextInputHandler = nullptr;
+  }
+  mGeckoChild = nullptr;
+
+  // Just in case we're destroyed abruptly and missed the draggingExited
+  // or performDragOperation message.
+  NS_IF_RELEASE(mDragService);
+}
+
+// mozView method, return our gecko child view widget. Note this does not AddRef.
+- (nsIWidget*) widget
+{
+  return static_cast<nsIWidget*>(mGeckoChild);
+}
+
+- (void)systemMetricsChanged
+{
+  if (mGeckoChild)
+    mGeckoChild->NotifyThemeChanged();
+}
+
+- (void)scrollbarSystemMetricChanged
+{
+  [self systemMetricsChanged];
+
+  if (mGeckoChild) {
+    nsIWidgetListener* listener = mGeckoChild->GetWidgetListener();
+    if (listener) {
+      nsIPresShell* presShell = listener->GetPresShell();
+      if (presShell) {
+        presShell->ReconstructFrames();
+      }
+    }
+  }
+}
+
+- (NSString*)description
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [NSString stringWithFormat:@"ChildView %p, gecko child %p, frame %@", self, mGeckoChild, NSStringFromRect([self frame])];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+// Make the origin of this view the topLeft corner (gecko origin) rather
+// than the bottomLeft corner (standard cocoa origin).
+- (BOOL)isFlipped
+{
+  return YES;
+}
+
+- (BOOL)isOpaque
+{
+  return [[self window] isOpaque];
+}
+
+- (void)sendFocusEvent:(EventMessage)eventMessage
+{
+  if (!mGeckoChild)
+    return;
+
+  nsEventStatus status = nsEventStatus_eIgnore;
+  WidgetGUIEvent focusGuiEvent(true, eventMessage, mGeckoChild);
+  focusGuiEvent.mTime = PR_IntervalNow();
+  mGeckoChild->DispatchEvent(&focusGuiEvent, status);
+}
+
+// We accept key and mouse events, so don't keep passing them up the chain. Allow
+// this to be a 'focused' widget for event dispatch.
+- (BOOL)acceptsFirstResponder
+{
+  return YES;
+}
+
+// Accept mouse down events on background windows
+- (BOOL)acceptsFirstMouse:(NSEvent*)aEvent
+{
+  if (![[self window] isKindOfClass:[PopupWindow class]]) {
+    // We rely on this function to tell us that the mousedown was on a
+    // background window. Inside mouseDown we can't tell whether we were
+    // inactive because at that point we've already been made active.
+    // Unfortunately, acceptsFirstMouse is called for PopupWindows even when
+    // their parent window is active, so ignore this on them for now.
+    mClickThroughMouseDownEvent = [aEvent retain];
+  }
+  return YES;
+}
+
+- (BOOL)mouseDownCanMoveWindow
+{
+  // Return YES so that parts of this view can be draggable. The non-draggable
+  // parts will be covered by NSViews that return NO from
+  // mouseDownCanMoveWindow and thus override draggability from the inside.
+  // These views are assembled in nsChildView::UpdateWindowDraggingRegion.
+  return YES;
+}
+
+-(void)updateGLContext
+{
+  [mGLContext setView:mPixelHostingView];
+  [mGLContext update];
+}
+
+- (void)_surfaceNeedsUpdate:(NSNotification*)notification
+{
+  if (mGLContext) {
+    CGLLockContext((CGLContextObj)[mGLContext CGLContextObj]);
+    mNeedsGLUpdate = YES;
+    CGLUnlockContext((CGLContextObj)[mGLContext CGLContextObj]);
+  }
+}
+
+- (void)viewDidChangeBackingProperties
+{
+  [super viewDidChangeBackingProperties];
+  if (mGeckoChild) {
+    // actually, it could be the color space that's changed,
+    // but we can't tell the difference here except by retrieving
+    // the backing scale factor and comparing to the old value
+    mGeckoChild->BackingScaleFactorChanged();
+  }
+}
+
+- (BOOL)isCoveringTitlebar
+{
+  return [[self window] isKindOfClass:[BaseWindow class]] &&
+         [(BaseWindow*)[self window] mainChildView] == self &&
+         [(BaseWindow*)[self window] drawsContentsIntoWindowFrame];
+}
+
+- (void)viewWillStartLiveResize
+{
+  nsCOMPtr<nsIObserverService> observerService = mozilla::services::GetObserverService();
+
+  if (!observerService) {
+    return;
+  }
+
+  observerService->NotifyObservers(nullptr, "live-resize-start", nullptr);
+}
+
+- (void)viewDidEndLiveResize
+{
+  nsCOMPtr<nsIObserverService> observerService = mozilla::services::GetObserverService();
+
+  if (!observerService) {
+    return;
+  }
+
+  observerService->NotifyObservers(nullptr, "live-resize-end", nullptr);
+}
+
+- (NSColor*)vibrancyFillColorForThemeGeometryType:(nsITheme::ThemeGeometryType)aThemeGeometryType
+{
+  if (!mGeckoChild) {
+    return [NSColor whiteColor];
+  }
+  return mGeckoChild->VibrancyFillColorForThemeGeometryType(aThemeGeometryType);
+}
+
+- (NSColor*)vibrancyFontSmoothingBackgroundColorForThemeGeometryType:(nsITheme::ThemeGeometryType)aThemeGeometryType
+{
+  if (!mGeckoChild) {
+    return [NSColor clearColor];
+  }
+  return mGeckoChild->VibrancyFontSmoothingBackgroundColorForThemeGeometryType(aThemeGeometryType);
+}
+
+- (LayoutDeviceIntRegion)nativeDirtyRegionWithBoundingRect:(NSRect)aRect
+{
+  LayoutDeviceIntRect boundingRect = mGeckoChild->CocoaPointsToDevPixels(aRect);
+  const NSRect *rects;
+  NSInteger count;
+  [mPixelHostingView getRectsBeingDrawn:&rects count:&count];
+
+  if (count > MAX_RECTS_IN_REGION) {
+    return boundingRect;
+  }
+
+  LayoutDeviceIntRegion region;
+  for (NSInteger i = 0; i < count; ++i) {
+    region.Or(region, mGeckoChild->CocoaPointsToDevPixels(rects[i]));
+  }
+  region.And(region, boundingRect);
+  return region;
+}
+
+// The display system has told us that a portion of our view is dirty. Tell
+// gecko to paint it
+// This method is called from mPixelHostingView's drawRect handler.
+- (void)doDrawRect:(NSRect)aRect
+{
+  if (!NS_IsMainThread()) {
+    // In the presence of CoreAnimation, this method can sometimes be called on
+    // a non-main thread. Ignore those calls because Gecko can only react to
+    // them on the main thread.
+    return;
+  }
+
+  if (!mGeckoChild || !mGeckoChild->IsVisible())
+    return;
+  CGContextRef cgContext = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
+
+  if ([self isUsingOpenGL]) {
+    // Since this view is usually declared as opaque, the window's pixel
+    // buffer may now contain garbage which we need to prevent from reaching
+    // the screen. The only place where garbage can show is in the window
+    // corners and the vibrant regions of the window - the rest of the window
+    // is covered by opaque content in our OpenGL surface.
+    // So we need to clear the pixel buffer contents in these areas.
+    [self clearCorners];
+
+    // Force a sync OMTC composite into the OpenGL context and return.
+    LayoutDeviceIntRect geckoBounds = mGeckoChild->GetBounds();
+    LayoutDeviceIntRegion region(geckoBounds);
+
+    mGeckoChild->PaintWindow(region);
+    return;
+  }
+
+  PROFILER_LABEL("ChildView", "drawRect",
+    js::ProfileEntry::Category::GRAPHICS);
+
+  // The CGContext that drawRect supplies us with comes with a transform that
+  // scales one user space unit to one Cocoa point, which can consist of
+  // multiple dev pixels. But Gecko expects its supplied context to be scaled
+  // to device pixels, so we need to reverse the scaling.
+  double scale = mGeckoChild->BackingScaleFactor();
+  CGContextSaveGState(cgContext);
+  CGContextScaleCTM(cgContext, 1.0 / scale, 1.0 / scale);
+
+  NSSize viewSize = [self bounds].size;
+  gfx::IntSize backingSize = gfx::IntSize::Truncate(viewSize.width * scale, viewSize.height * scale);
+  LayoutDeviceIntRegion region = [self nativeDirtyRegionWithBoundingRect:aRect];
+
+  bool painted = mGeckoChild->PaintWindowInContext(cgContext, region, backingSize);
+
+  // Undo the scale transform so that from now on the context is in
+  // CocoaPoints again.
+  CGContextRestoreGState(cgContext);
+
+  if (!painted && [mPixelHostingView isOpaque]) {
+    // Gecko refused to draw, but we've claimed to be opaque, so we have to
+    // draw something--fill with white.
+    CGContextSetRGBFillColor(cgContext, 1, 1, 1, 1);
+    CGContextFillRect(cgContext, NSRectToCGRect(aRect));
+  }
+
+  if ([self isCoveringTitlebar]) {
+    [self drawTitleString];
+    [self drawTitlebarHighlight];
+    [self maskTopCornersInContext:cgContext];
+  }
+}
+
+- (BOOL)isUsingOpenGL
+{
+  if (!mGeckoChild || ![self window])
+    return NO;
+
+  return mGLContext || mUsingOMTCompositor;
+}
+
+
+- (BOOL)hasRoundedBottomCorners
+{
+  return [[self window] respondsToSelector:@selector(bottomCornerRounded)] &&
+  [[self window] bottomCornerRounded];
+}
+
+- (CGFloat)cornerRadius
+{
+  NSView* frameView = [[[self window] contentView] superview];
+  if (!frameView || ![frameView respondsToSelector:@selector(roundedCornerRadius)])
+    return 4.0f;
+  return [frameView roundedCornerRadius];
+}
+
+-(void)setGLOpaque:(BOOL)aOpaque
+{
+  CGLLockContext((CGLContextObj)[mGLContext CGLContextObj]);
+  // Make the context opaque for fullscreen (since it performs better), and transparent
+  // for windowed (since we need it for rounded corners).
+  GLint opaque = aOpaque ? 1 : 0;
+  [mGLContext setValues:&opaque forParameter:NSOpenGLCPSurfaceOpacity];
+  CGLUnlockContext((CGLContextObj)[mGLContext CGLContextObj]);
+}
+
+// Accelerated windows have two NSSurfaces:
+//  (1) The window's pixel buffer in the back and
+//  (2) the OpenGL view in the front.
+// These two surfaces are composited by the window manager. Drawing into the
+// CGContext which is provided by drawRect ends up in (1).
+// When our window has rounded corners, the OpenGL view has transparent pixels
+// in the corners. In these places the contents of the window's pixel buffer
+// can show through. So we need to make sure that the pixel buffer is
+// transparent in the corners so that no garbage reaches the screen.
+// The contents of the pixel buffer in the rest of the window don't matter
+// because they're covered by opaque pixels of the OpenGL context.
+// Making the corners transparent works even though our window is
+// declared "opaque" (in the NSWindow's isOpaque method).
+- (void)clearCorners
+{
+  CGFloat radius = [self cornerRadius];
+  CGFloat w = [self bounds].size.width, h = [self bounds].size.height;
+  [[NSColor clearColor] set];
+
+  if ([self isCoveringTitlebar]) {
+    NSRectFill(NSMakeRect(0, 0, radius, radius));
+    NSRectFill(NSMakeRect(w - radius, 0, radius, radius));
+  }
+
+  if ([self hasRoundedBottomCorners]) {
+    NSRectFill(NSMakeRect(0, h - radius, radius, radius));
+    NSRectFill(NSMakeRect(w - radius, h - radius, radius, radius));
+  }
+}
+
+// This is the analog of nsChildView::MaybeDrawRoundedCorners for CGContexts.
+// We only need to mask the top corners here because Cocoa does the masking
+// for the window's bottom corners automatically (starting with 10.7).
+- (void)maskTopCornersInContext:(CGContextRef)aContext
+{
+  CGFloat radius = [self cornerRadius];
+  int32_t devPixelCornerRadius = mGeckoChild->CocoaPointsToDevPixels(radius);
+
+  // First make sure that mTopLeftCornerMask is set up.
+  if (!mTopLeftCornerMask ||
+      int32_t(CGImageGetWidth(mTopLeftCornerMask)) != devPixelCornerRadius) {
+    CGImageRelease(mTopLeftCornerMask);
+    CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
+    CGContextRef imgCtx = CGBitmapContextCreate(NULL,
+                                                devPixelCornerRadius,
+                                                devPixelCornerRadius,
+                                                8, devPixelCornerRadius * 4,
+                                                rgb, kCGImageAlphaPremultipliedFirst);
+    CGColorSpaceRelease(rgb);
+    DrawTopLeftCornerMask(imgCtx, devPixelCornerRadius);
+    mTopLeftCornerMask = CGBitmapContextCreateImage(imgCtx);
+    CGContextRelease(imgCtx);
+  }
+
+  // kCGBlendModeDestinationIn is the secret sauce which allows us to erase
+  // already painted pixels. It's defined as R = D * Sa: multiply all channels
+  // of the destination pixel with the alpha of the source pixel. In our case,
+  // the source is mTopLeftCornerMask.
+  CGContextSaveGState(aContext);
+  CGContextSetBlendMode(aContext, kCGBlendModeDestinationIn);
+
+  CGRect destRect = CGRectMake(0, 0, radius, radius);
+
+  // Erase the top left corner...
+  CGContextDrawImage(aContext, destRect, mTopLeftCornerMask);
+
+  // ... and the top right corner.
+  CGContextTranslateCTM(aContext, [self bounds].size.width, 0);
+  CGContextScaleCTM(aContext, -1, 1);
+  CGContextDrawImage(aContext, destRect, mTopLeftCornerMask);
+
+  CGContextRestoreGState(aContext);
+}
+
+- (void)drawTitleString
+{
+  BaseWindow* window = (BaseWindow*)[self window];
+  if (![window wantsTitleDrawn]) {
+    return;
+  }
+
+  NSView* frameView = [[window contentView] superview];
+  if (![frameView respondsToSelector:@selector(_drawTitleBar:)]) {
+    return;
+  }
+
+  NSGraphicsContext* oldContext = [NSGraphicsContext currentContext];
+  CGContextRef ctx = (CGContextRef)[oldContext graphicsPort];
+  CGContextSaveGState(ctx);
+  if ([oldContext isFlipped] != [frameView isFlipped]) {
+    CGContextTranslateCTM(ctx, 0, [self bounds].size.height);
+    CGContextScaleCTM(ctx, 1, -1);
+  }
+  [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:ctx flipped:[frameView isFlipped]]];
+  [frameView _drawTitleBar:[frameView bounds]];
+  CGContextRestoreGState(ctx);
+  [NSGraphicsContext setCurrentContext:oldContext];
+}
+
+- (void)drawTitlebarHighlight
+{
+  DrawTitlebarHighlight([self bounds].size, [self cornerRadius],
+                        mGeckoChild->DevPixelsToCocoaPoints(1));
+}
+
+- (void)viewWillDraw
+{
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  if (mGeckoChild) {
+    // The OS normally *will* draw our NSWindow, no matter what we do here.
+    // But Gecko can delete our parent widget(s) (along with mGeckoChild)
+    // while processing a paint request, which closes our NSWindow and
+    // makes the OS throw an NSInternalInconsistencyException assertion when
+    // it tries to draw it.  Sometimes the OS also aborts the browser process.
+    // So we need to retain our parent(s) here and not release it/them until
+    // the next time through the main thread's run loop.  When we do this we
+    // also need to retain and release mGeckoChild, which holds a strong
+    // reference to us.  See bug 550392.
+    nsIWidget* parent = mGeckoChild->GetParent();
+    if (parent) {
+      nsTArray<nsCOMPtr<nsIWidget>> widgetArray;
+      while (parent) {
+        widgetArray.AppendElement(parent);
+        parent = parent->GetParent();
+      }
+      widgetArray.AppendElement(mGeckoChild);
+      nsCOMPtr<nsIRunnable> releaserRunnable =
+        new WidgetsReleaserRunnable(Move(widgetArray));
+      NS_DispatchToMainThread(releaserRunnable);
+    }
+
+    if ([self isUsingOpenGL]) {
+      if (ShadowLayerForwarder* slf = mGeckoChild->GetLayerManager()->AsShadowForwarder()) {
+        slf->WindowOverlayChanged();
+      }
+    }
+
+    mGeckoChild->WillPaintWindow();
+  }
+  [super viewWillDraw];
+}
+
+#if USE_CLICK_HOLD_CONTEXTMENU
+//
+// -clickHoldCallback:
+//
+// called from a timer two seconds after a mouse down to see if we should display
+// a context menu (click-hold). |anEvent| is the original mouseDown event. If we're
+// still in that mouseDown by this time, put up the context menu, otherwise just
+// fuhgeddaboutit. |anEvent| has been retained by the OS until after this callback
+// fires so we're ok there.
+//
+// This code currently messes in a bunch of edge cases (bugs 234751, 232964, 232314)
+// so removing it until we get it straightened out.
+//
+- (void)clickHoldCallback:(id)theEvent;
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if( theEvent == [NSApp currentEvent] ) {
+    // we're still in the middle of the same mousedown event here, activate
+    // click-hold context menu by triggering the right mouseDown action.
+    NSEvent* clickHoldEvent = [NSEvent mouseEventWithType:NSRightMouseDown
+                                                  location:[theEvent locationInWindow]
+                                             modifierFlags:[theEvent modifierFlags]
+                                                 timestamp:[theEvent timestamp]
+                                              windowNumber:[theEvent windowNumber]
+                                                   context:[theEvent context]
+                                               eventNumber:[theEvent eventNumber]
+                                                clickCount:[theEvent clickCount]
+                                                  pressure:[theEvent pressure]];
+    [self rightMouseDown:clickHoldEvent];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+#endif
+
+// If we've just created a non-native context menu, we need to mark it as
+// such and let the OS (and other programs) know when it opens and closes
+// (this is how the OS knows to close other programs' context menus when
+// ours open).  We send the initial notification here, but others are sent
+// in nsCocoaWindow::Show().
+- (void)maybeInitContextMenuTracking
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+#ifdef MOZ_USE_NATIVE_POPUP_WINDOWS
+  return;
+#endif /* MOZ_USE_NATIVE_POPUP_WINDOWS */
+
+  nsIRollupListener* rollupListener = nsBaseWidget::GetActiveRollupListener();
+  NS_ENSURE_TRUE_VOID(rollupListener);
+  nsCOMPtr<nsIWidget> widget = rollupListener->GetRollupWidget();
+  NS_ENSURE_TRUE_VOID(widget);
+
+  NSWindow *popupWindow = (NSWindow*)widget->GetNativeData(NS_NATIVE_WINDOW);
+  if (!popupWindow || ![popupWindow isKindOfClass:[PopupWindow class]])
+    return;
+
+  [[NSDistributedNotificationCenter defaultCenter]
+    postNotificationName:@"com.apple.HIToolbox.beginMenuTrackingNotification"
+                  object:@"org.mozilla.gecko.PopupWindow"];
+  [(PopupWindow*)popupWindow setIsContextMenu:YES];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Returns true if the event should no longer be processed, false otherwise.
+// This does not return whether or not anything was rolled up.
+- (BOOL)maybeRollup:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  BOOL consumeEvent = NO;
+
+  nsIRollupListener* rollupListener = nsBaseWidget::GetActiveRollupListener();
+  NS_ENSURE_TRUE(rollupListener, false);
+  nsCOMPtr<nsIWidget> rollupWidget = rollupListener->GetRollupWidget();
+  if (rollupWidget) {
+    NSWindow* currentPopup = static_cast<NSWindow*>(rollupWidget->GetNativeData(NS_NATIVE_WINDOW));
+    if (!nsCocoaUtils::IsEventOverWindow(theEvent, currentPopup)) {
+      // event is not over the rollup window, default is to roll up
+      bool shouldRollup = true;
+
+      // check to see if scroll events should roll up the popup
+      if ([theEvent type] == NSScrollWheel) {
+        shouldRollup = rollupListener->ShouldRollupOnMouseWheelEvent();
+        // consume scroll events that aren't over the popup
+        // unless the popup is an arrow panel
+        consumeEvent = rollupListener->ShouldConsumeOnMouseWheelEvent();
+      }
+
+      // if we're dealing with menus, we probably have submenus and
+      // we don't want to rollup if the click is in a parent menu of
+      // the current submenu
+      uint32_t popupsToRollup = UINT32_MAX;
+      AutoTArray<nsIWidget*, 5> widgetChain;
+      uint32_t sameTypeCount = rollupListener->GetSubmenuWidgetChain(&widgetChain);
+      for (uint32_t i = 0; i < widgetChain.Length(); i++) {
+        nsIWidget* widget = widgetChain[i];
+        NSWindow* currWindow = (NSWindow*)widget->GetNativeData(NS_NATIVE_WINDOW);
+        if (nsCocoaUtils::IsEventOverWindow(theEvent, currWindow)) {
+          // don't roll up if the mouse event occurred within a menu of the
+          // same type. If the mouse event occurred in a menu higher than
+          // that, roll up, but pass the number of popups to Rollup so
+          // that only those of the same type close up.
+          if (i < sameTypeCount) {
+            shouldRollup = false;
+          }
+          else {
+            popupsToRollup = sameTypeCount;
+          }
+          break;
+        }
+      }
+
+      if (shouldRollup) {
+        if ([theEvent type] == NSLeftMouseDown) {
+          NSPoint point = [NSEvent mouseLocation];
+          FlipCocoaScreenCoordinate(point);
+          gfx::IntPoint pos = gfx::IntPoint::Truncate(point.x, point.y);
+          consumeEvent = (BOOL)rollupListener->Rollup(popupsToRollup, true, &pos, nullptr);
+        }
+        else {
+          consumeEvent = (BOOL)rollupListener->Rollup(popupsToRollup, true, nullptr, nullptr);
+        }
+      }
+    }
+  }
+
+  return consumeEvent;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+/*
+ * In OS X Mountain Lion and above, smart zoom gestures are implemented in
+ * smartMagnifyWithEvent. In OS X Lion, they are implemented in
+ * magnifyWithEvent. See inline comments for more info.
+ *
+ * The prototypes swipeWithEvent, beginGestureWithEvent, magnifyWithEvent,
+ * smartMagnifyWithEvent, rotateWithEvent, and endGestureWithEvent were
+ * obtained from the following links:
+ * https://developer.apple.com/library/mac/#documentation/Cocoa/Reference/ApplicationKit/Classes/NSResponder_Class/Reference/Reference.html
+ * https://developer.apple.com/library/mac/#releasenotes/Cocoa/AppKit.html
+ */
+
+- (void)swipeWithEvent:(NSEvent *)anEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!anEvent || !mGeckoChild)
+    return;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  float deltaX = [anEvent deltaX];  // left=1.0, right=-1.0
+  float deltaY = [anEvent deltaY];  // up=1.0, down=-1.0
+
+  // Setup the "swipe" event.
+  WidgetSimpleGestureEvent geckoEvent(true, eSwipeGesture, mGeckoChild);
+  [self convertCocoaMouseEvent:anEvent toGeckoEvent:&geckoEvent];
+
+  // Record the left/right direction.
+  if (deltaX > 0.0)
+    geckoEvent.mDirection |= nsIDOMSimpleGestureEvent::DIRECTION_LEFT;
+  else if (deltaX < 0.0)
+    geckoEvent.mDirection |= nsIDOMSimpleGestureEvent::DIRECTION_RIGHT;
+
+  // Record the up/down direction.
+  if (deltaY > 0.0)
+    geckoEvent.mDirection |= nsIDOMSimpleGestureEvent::DIRECTION_UP;
+  else if (deltaY < 0.0)
+    geckoEvent.mDirection |= nsIDOMSimpleGestureEvent::DIRECTION_DOWN;
+
+  // Send the event.
+  mGeckoChild->DispatchWindowEvent(geckoEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)beginGestureWithEvent:(NSEvent *)anEvent
+{
+  if (!anEvent)
+    return;
+
+  mGestureState = eGestureState_StartGesture;
+  mCumulativeMagnification = 0;
+  mCumulativeRotation = 0.0;
+}
+
+- (void)magnifyWithEvent:(NSEvent *)anEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!anEvent || !mGeckoChild)
+    return;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  float deltaZ = [anEvent deltaZ];
+
+  EventMessage msg;
+  switch (mGestureState) {
+  case eGestureState_StartGesture:
+    msg = eMagnifyGestureStart;
+    mGestureState = eGestureState_MagnifyGesture;
+    break;
+
+  case eGestureState_MagnifyGesture:
+    msg = eMagnifyGestureUpdate;
+    break;
+
+  case eGestureState_None:
+  case eGestureState_RotateGesture:
+  default:
+    return;
+  }
+
+  // Setup the event.
+  WidgetSimpleGestureEvent geckoEvent(true, msg, mGeckoChild);
+  geckoEvent.mDelta = deltaZ;
+  [self convertCocoaMouseEvent:anEvent toGeckoEvent:&geckoEvent];
+
+  // Send the event.
+  mGeckoChild->DispatchWindowEvent(geckoEvent);
+
+  // Keep track of the cumulative magnification for the final "magnify" event.
+  mCumulativeMagnification += deltaZ;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)smartMagnifyWithEvent:(NSEvent *)anEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!anEvent || !mGeckoChild) {
+    return;
+  }
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  // Setup the "double tap" event.
+  WidgetSimpleGestureEvent geckoEvent(true, eTapGesture, mGeckoChild);
+  [self convertCocoaMouseEvent:anEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.mClickCount = 1;
+
+  // Send the event.
+  mGeckoChild->DispatchWindowEvent(geckoEvent);
+
+  // Clear the gesture state
+  mGestureState = eGestureState_None;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)rotateWithEvent:(NSEvent *)anEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!anEvent || !mGeckoChild)
+    return;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  float rotation = [anEvent rotation];
+
+  EventMessage msg;
+  switch (mGestureState) {
+  case eGestureState_StartGesture:
+    msg = eRotateGestureStart;
+    mGestureState = eGestureState_RotateGesture;
+    break;
+
+  case eGestureState_RotateGesture:
+    msg = eRotateGestureUpdate;
+    break;
+
+  case eGestureState_None:
+  case eGestureState_MagnifyGesture:
+  default:
+    return;
+  }
+
+  // Setup the event.
+  WidgetSimpleGestureEvent geckoEvent(true, msg, mGeckoChild);
+  [self convertCocoaMouseEvent:anEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.mDelta = -rotation;
+  if (rotation > 0.0) {
+    geckoEvent.mDirection = nsIDOMSimpleGestureEvent::ROTATION_COUNTERCLOCKWISE;
+  } else {
+    geckoEvent.mDirection = nsIDOMSimpleGestureEvent::ROTATION_CLOCKWISE;
+  }
+
+  // Send the event.
+  mGeckoChild->DispatchWindowEvent(geckoEvent);
+
+  // Keep track of the cumulative rotation for the final "rotate" event.
+  mCumulativeRotation += rotation;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)endGestureWithEvent:(NSEvent *)anEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!anEvent || !mGeckoChild) {
+    // Clear the gestures state if we cannot send an event.
+    mGestureState = eGestureState_None;
+    mCumulativeMagnification = 0.0;
+    mCumulativeRotation = 0.0;
+    return;
+  }
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  switch (mGestureState) {
+  case eGestureState_MagnifyGesture:
+    {
+      // Setup the "magnify" event.
+      WidgetSimpleGestureEvent geckoEvent(true, eMagnifyGesture, mGeckoChild);
+      geckoEvent.mDelta = mCumulativeMagnification;
+      [self convertCocoaMouseEvent:anEvent toGeckoEvent:&geckoEvent];
+
+      // Send the event.
+      mGeckoChild->DispatchWindowEvent(geckoEvent);
+    }
+    break;
+
+  case eGestureState_RotateGesture:
+    {
+      // Setup the "rotate" event.
+      WidgetSimpleGestureEvent geckoEvent(true, eRotateGesture, mGeckoChild);
+      [self convertCocoaMouseEvent:anEvent toGeckoEvent:&geckoEvent];
+      geckoEvent.mDelta = -mCumulativeRotation;
+      if (mCumulativeRotation > 0.0) {
+        geckoEvent.mDirection = nsIDOMSimpleGestureEvent::ROTATION_COUNTERCLOCKWISE;
+      } else {
+        geckoEvent.mDirection = nsIDOMSimpleGestureEvent::ROTATION_CLOCKWISE;
+      }
+
+      // Send the event.
+      mGeckoChild->DispatchWindowEvent(geckoEvent);
+    }
+    break;
+
+  case eGestureState_None:
+  case eGestureState_StartGesture:
+  default:
+    break;
+  }
+
+  // Clear the gestures state.
+  mGestureState = eGestureState_None;
+  mCumulativeMagnification = 0.0;
+  mCumulativeRotation = 0.0;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (bool)shouldConsiderStartingSwipeFromEvent:(NSEvent*)anEvent
+{
+  // This method checks whether the AppleEnableSwipeNavigateWithScrolls global
+  // preference is set.  If it isn't, fluid swipe tracking is disabled, and a
+  // horizontal two-finger gesture is always a scroll (even in Safari).  This
+  // preference can't (currently) be set from the Preferences UI -- only using
+  // 'defaults write'.
+  if (![NSEvent isSwipeTrackingFromScrollEventsEnabled]) {
+    return false;
+  }
+
+  // Only initiate horizontal tracking for gestures that have just begun --
+  // otherwise a scroll to one side of the page can have a swipe tacked on
+  // to it.
+  NSEventPhase eventPhase = nsCocoaUtils::EventPhase(anEvent);
+  if ([anEvent type] != NSScrollWheel ||
+      eventPhase != NSEventPhaseBegan ||
+      ![anEvent hasPreciseScrollingDeltas]) {
+    return false;
+  }
+
+  // Only initiate horizontal tracking for events whose horizontal element is
+  // at least eight times larger than its vertical element. This minimizes
+  // performance problems with vertical scrolls (by minimizing the possibility
+  // that they'll be misinterpreted as horizontal swipes), while still
+  // tolerating a small vertical element to a true horizontal swipe.  The number
+  // '8' was arrived at by trial and error.
+  CGFloat deltaX = [anEvent scrollingDeltaX];
+  CGFloat deltaY = [anEvent scrollingDeltaY];
+  return std::abs(deltaX) > std::abs(deltaY) * 8;
+}
+
+- (void)setUsingOMTCompositor:(BOOL)aUseOMTC
+{
+  mUsingOMTCompositor = aUseOMTC;
+}
+
+// Returning NO from this method only disallows ordering on mousedown - in order
+// to prevent it for mouseup too, we need to call [NSApp preventWindowOrdering]
+// when handling the mousedown event.
+- (BOOL)shouldDelayWindowOrderingForEvent:(NSEvent*)aEvent
+{
+  // Always using system-provided window ordering for normal windows.
+  if (![[self window] isKindOfClass:[PopupWindow class]])
+    return NO;
+
+  // Don't reorder when we don't have a parent window, like when we're a
+  // context menu or a tooltip.
+  return ![[self window] parentWindow];
+}
+
+- (void)mouseDown:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if ([self shouldDelayWindowOrderingForEvent:theEvent]) {
+    [NSApp preventWindowOrdering];
+  }
+
+  // If we've already seen this event due to direct dispatch from menuForEvent:
+  // just bail; if not, remember it.
+  if (mLastMouseDownEvent == theEvent) {
+    [mLastMouseDownEvent release];
+    mLastMouseDownEvent = nil;
+    return;
+  }
+  else {
+    [mLastMouseDownEvent release];
+    mLastMouseDownEvent = [theEvent retain];
+  }
+
+  [gLastDragMouseDownEvent release];
+  gLastDragMouseDownEvent = [theEvent retain];
+
+  // We need isClickThrough because at this point the window we're in might
+  // already have become main, so the check for isMainWindow in
+  // WindowAcceptsEvent isn't enough. It also has to check isClickThrough.
+  BOOL isClickThrough = (theEvent == mClickThroughMouseDownEvent);
+  [mClickThroughMouseDownEvent release];
+  mClickThroughMouseDownEvent = nil;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  if ([self maybeRollup:theEvent] ||
+      !ChildViewMouseTracker::WindowAcceptsEvent([self window], theEvent, self, isClickThrough)) {
+    // Remember blocking because that means we want to block mouseup as well.
+    mBlockedLastMouseDown = YES;
+    return;
+  }
+
+#if USE_CLICK_HOLD_CONTEXTMENU
+  // fire off timer to check for click-hold after two seconds. retains |theEvent|
+  [self performSelector:@selector(clickHoldCallback:) withObject:theEvent afterDelay:2.0];
+#endif
+
+  // in order to send gecko events we'll need a gecko widget
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  NSUInteger modifierFlags = [theEvent modifierFlags];
+
+  WidgetMouseEvent geckoEvent(true, eMouseDown, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+
+  NSInteger clickCount = [theEvent clickCount];
+  if (mBlockedLastMouseDown && clickCount > 1) {
+    // Don't send a double click if the first click of the double click was
+    // blocked.
+    clickCount--;
+  }
+  geckoEvent.mClickCount = clickCount;
+
+  if (modifierFlags & NSControlKeyMask)
+    geckoEvent.button = WidgetMouseEvent::eRightButton;
+  else
+    geckoEvent.button = WidgetMouseEvent::eLeftButton;
+
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+  mBlockedLastMouseDown = NO;
+
+  // XXX maybe call markedTextSelectionChanged:client: here?
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)mouseUp:(NSEvent *)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mGeckoChild || mBlockedLastMouseDown)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  WidgetMouseEvent geckoEvent(true, eMouseUp, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  if ([theEvent modifierFlags] & NSControlKeyMask)
+    geckoEvent.button = WidgetMouseEvent::eRightButton;
+  else
+    geckoEvent.button = WidgetMouseEvent::eLeftButton;
+
+  // This might destroy our widget (and null out mGeckoChild).
+  bool defaultPrevented =
+    (mGeckoChild->DispatchInputEvent(&geckoEvent) == nsEventStatus_eConsumeNoDefault);
+
+  // Check to see if we are double-clicking in the titlebar.
+  CGFloat locationInTitlebar = [[self window] frame].size.height - [theEvent locationInWindow].y;
+  LayoutDeviceIntPoint pos = geckoEvent.mRefPoint;
+  if (!defaultPrevented && [theEvent clickCount] == 2 &&
+      !mGeckoChild->GetNonDraggableRegion().Contains(pos.x, pos.y) &&
+      [[self window] isKindOfClass:[ToolbarWindow class]] &&
+      (locationInTitlebar < [(ToolbarWindow*)[self window] titlebarHeight] ||
+       locationInTitlebar < [(ToolbarWindow*)[self window] unifiedToolbarHeight])) {
+    if ([self shouldZoomOnDoubleClick]) {
+      [[self window] performZoom:nil];
+    } else if ([self shouldMinimizeOnTitlebarDoubleClick]) {
+      NSButton *minimizeButton = [[self window] standardWindowButton:NSWindowMiniaturizeButton];
+      [minimizeButton performClick:self];
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)sendMouseEnterOrExitEvent:(NSEvent*)aEvent
+                            enter:(BOOL)aEnter
+                         exitFrom:(WidgetMouseEvent::ExitFrom)aExitFrom
+{
+  if (!mGeckoChild)
+    return;
+
+  NSPoint windowEventLocation = nsCocoaUtils::EventLocationForWindow(aEvent, [self window]);
+  NSPoint localEventLocation = [self convertPoint:windowEventLocation fromView:nil];
+
+  EventMessage msg = aEnter ? eMouseEnterIntoWidget : eMouseExitFromWidget;
+  WidgetMouseEvent event(true, msg, mGeckoChild, WidgetMouseEvent::eReal);
+  event.mRefPoint = mGeckoChild->CocoaPointsToDevPixels(localEventLocation);
+
+  event.mExitFrom = aExitFrom;
+
+  nsEventStatus status; // ignored
+  mGeckoChild->DispatchEvent(&event, status);
+}
+
+- (void)handleMouseMoved:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  WidgetMouseEvent geckoEvent(true, eMouseMove, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)mouseDragged:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  gLastDragView = self;
+
+  WidgetMouseEvent geckoEvent(true, eMouseMove, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+
+  // Note, sending the above event might have destroyed our widget since we didn't retain.
+  // Fine so long as we don't access any local variables from here on.
+  gLastDragView = nil;
+
+  // XXX maybe call markedTextSelectionChanged:client: here?
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)rightMouseDown:(NSEvent *)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  [self maybeRollup:theEvent];
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  // The right mouse went down, fire off a right mouse down event to gecko
+  WidgetMouseEvent geckoEvent(true, eMouseDown, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.button = WidgetMouseEvent::eRightButton;
+  geckoEvent.mClickCount = [theEvent clickCount];
+
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+  if (!mGeckoChild)
+    return;
+
+  // Let the superclass do the context menu stuff.
+  [super rightMouseDown:theEvent];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)rightMouseUp:(NSEvent *)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  WidgetMouseEvent geckoEvent(true, eMouseUp, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.button = WidgetMouseEvent::eRightButton;
+  geckoEvent.mClickCount = [theEvent clickCount];
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)rightMouseDragged:(NSEvent*)theEvent
+{
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  WidgetMouseEvent geckoEvent(true, eMouseMove, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.button = WidgetMouseEvent::eRightButton;
+
+  // send event into Gecko by going directly to the
+  // the widget.
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+}
+
+- (void)otherMouseDown:(NSEvent *)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  if ([self maybeRollup:theEvent] ||
+      !ChildViewMouseTracker::WindowAcceptsEvent([self window], theEvent, self))
+    return;
+
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  WidgetMouseEvent geckoEvent(true, eMouseDown, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.button = WidgetMouseEvent::eMiddleButton;
+  geckoEvent.mClickCount = [theEvent clickCount];
+
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)otherMouseUp:(NSEvent *)theEvent
+{
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  WidgetMouseEvent geckoEvent(true, eMouseUp, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.button = WidgetMouseEvent::eMiddleButton;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+}
+
+- (void)otherMouseDragged:(NSEvent*)theEvent
+{
+  if (!mGeckoChild)
+    return;
+  if (mTextInputHandler->OnHandleEvent(theEvent)) {
+    return;
+  }
+
+  WidgetMouseEvent geckoEvent(true, eMouseMove, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.button = WidgetMouseEvent::eMiddleButton;
+
+  // send event into Gecko by going directly to the
+  // the widget.
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+}
+
+- (void)sendWheelStartOrStop:(EventMessage)msg forEvent:(NSEvent *)theEvent
+{
+  WidgetWheelEvent wheelEvent(true, msg, mGeckoChild);
+  [self convertCocoaMouseWheelEvent:theEvent toGeckoEvent:&wheelEvent];
+  mExpectingWheelStop = (msg == eWheelOperationStart);
+  mGeckoChild->DispatchInputEvent(wheelEvent.AsInputEvent());
+}
+
+- (void)sendWheelCondition:(BOOL)condition
+                     first:(EventMessage)first
+                    second:(EventMessage)second
+                  forEvent:(NSEvent *)theEvent
+{
+  if (mExpectingWheelStop == condition) {
+    [self sendWheelStartOrStop:first forEvent:theEvent];
+  }
+  [self sendWheelStartOrStop:second forEvent:theEvent];
+}
+
+static PanGestureInput::PanGestureType
+PanGestureTypeForEvent(NSEvent* aEvent)
+{
+  switch (nsCocoaUtils::EventPhase(aEvent)) {
+    case NSEventPhaseMayBegin:
+      return PanGestureInput::PANGESTURE_MAYSTART;
+    case NSEventPhaseCancelled:
+      return PanGestureInput::PANGESTURE_CANCELLED;
+    case NSEventPhaseBegan:
+      return PanGestureInput::PANGESTURE_START;
+    case NSEventPhaseChanged:
+      return PanGestureInput::PANGESTURE_PAN;
+    case NSEventPhaseEnded:
+      return PanGestureInput::PANGESTURE_END;
+    case NSEventPhaseNone:
+      switch (nsCocoaUtils::EventMomentumPhase(aEvent)) {
+        case NSEventPhaseBegan:
+          return PanGestureInput::PANGESTURE_MOMENTUMSTART;
+        case NSEventPhaseChanged:
+          return PanGestureInput::PANGESTURE_MOMENTUMPAN;
+        case NSEventPhaseEnded:
+          return PanGestureInput::PANGESTURE_MOMENTUMEND;
+        default:
+          NS_ERROR("unexpected event phase");
+          return PanGestureInput::PANGESTURE_PAN;
+      }
+    default:
+      NS_ERROR("unexpected event phase");
+      return PanGestureInput::PANGESTURE_PAN;
+  }
+}
+
+static int32_t RoundUp(double aDouble)
+{
+  return aDouble < 0 ? static_cast<int32_t>(floor(aDouble)) :
+                       static_cast<int32_t>(ceil(aDouble));
+}
+
+static int32_t
+TakeLargestInt(gfx::Float* aFloat)
+{
+  int32_t result(*aFloat); // truncate towards zero
+  *aFloat -= result;
+  return result;
+}
+
+static gfx::IntPoint
+AccumulateIntegerDelta(NSEvent* aEvent)
+{
+  static gfx::Point sAccumulator(0.0f, 0.0f);
+  if (nsCocoaUtils::EventPhase(aEvent) == NSEventPhaseBegan) {
+    sAccumulator = gfx::Point(0.0f, 0.0f);
+  }
+  sAccumulator.x += [aEvent deltaX];
+  sAccumulator.y += [aEvent deltaY];
+  return gfx::IntPoint(TakeLargestInt(&sAccumulator.x),
+                       TakeLargestInt(&sAccumulator.y));
+}
+
+static gfx::IntPoint
+GetIntegerDeltaForEvent(NSEvent* aEvent)
+{
+  if (nsCocoaFeatures::OnSierraOrLater() && [aEvent hasPreciseScrollingDeltas]) {
+    // Pixel scroll events (events with hasPreciseScrollingDeltas == YES)
+    // carry pixel deltas in the scrollingDeltaX/Y fields and line scroll
+    // information in the deltaX/Y fields.
+    // Prior to 10.12, these line scroll fields would be zero for most pixel
+    // scroll events and non-zero for some, whenever at least a full line
+    // worth of pixel scrolling had accumulated. That's the behavior we want.
+    // Starting with 10.12 however, pixel scroll events no longer accumulate
+    // deltaX and deltaY; they just report floating point values for every
+    // single event. So we need to do our own accumulation.
+    return AccumulateIntegerDelta(aEvent);
+  }
+
+  // For line scrolls, or pre-10.12, just use the rounded up value of deltaX / deltaY.
+  return gfx::IntPoint(RoundUp([aEvent deltaX]), RoundUp([aEvent deltaY]));
+}
+
+- (void)scrollWheel:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  ChildViewMouseTracker::MouseScrolled(theEvent);
+
+  if ([self maybeRollup:theEvent]) {
+    return;
+  }
+
+  if (!mGeckoChild) {
+    return;
+  }
+
+  NSEventPhase phase = nsCocoaUtils::EventPhase(theEvent);
+  // Fire eWheelOperationStart/End events when 2 fingers touch/release the
+  // touchpad.
+  if (phase & NSEventPhaseMayBegin) {
+    [self sendWheelCondition:YES
+                       first:eWheelOperationEnd
+                      second:eWheelOperationStart
+                    forEvent:theEvent];
+  } else if (phase & (NSEventPhaseEnded | NSEventPhaseCancelled)) {
+    [self sendWheelCondition:NO
+                       first:eWheelOperationStart
+                      second:eWheelOperationEnd
+                    forEvent:theEvent];
+  }
+
+  if (!mGeckoChild) {
+    return;
+  }
+  RefPtr<nsChildView> geckoChildDeathGrip(mGeckoChild);
+
+  NSPoint locationInWindow = nsCocoaUtils::EventLocationForWindow(theEvent, [self window]);
+
+  // Use convertWindowCoordinatesRoundDown when converting the position to
+  // integer screen pixels in order to ensure that coordinates which are just
+  // inside the right / bottom edges of the window don't end up outside of the
+  // window after rounding.
+  ScreenPoint position = ViewAs<ScreenPixel>(
+    [self convertWindowCoordinatesRoundDown:locationInWindow],
+    PixelCastJustification::LayoutDeviceIsScreenForUntransformedEvent);
+
+  bool usePreciseDeltas = nsCocoaUtils::HasPreciseScrollingDeltas(theEvent) &&
+    Preferences::GetBool("mousewheel.enable_pixel_scrolling", true);
+  bool hasPhaseInformation = nsCocoaUtils::EventHasPhaseInformation(theEvent);
+
+  gfx::IntPoint lineOrPageDelta = -GetIntegerDeltaForEvent(theEvent);
+
+  Modifiers modifiers = nsCocoaUtils::ModifiersForEvent(theEvent);
+
+  NSTimeInterval beforeNow = [[NSProcessInfo processInfo] systemUptime] - [theEvent timestamp];
+  PRIntervalTime eventIntervalTime = PR_IntervalNow() - PR_MillisecondsToInterval(beforeNow * 1000);
+  TimeStamp eventTimeStamp = TimeStamp::Now() - TimeDuration::FromSeconds(beforeNow);
+
+  ScreenPoint preciseDelta;
+  if (usePreciseDeltas) {
+    CGFloat pixelDeltaX = 0, pixelDeltaY = 0;
+    nsCocoaUtils::GetScrollingDeltas(theEvent, &pixelDeltaX, &pixelDeltaY);
+    double scale = geckoChildDeathGrip->BackingScaleFactor();
+    preciseDelta = ScreenPoint(-pixelDeltaX * scale, -pixelDeltaY * scale);
+  }
+
+  if (usePreciseDeltas && hasPhaseInformation) {
+    PanGestureInput panEvent(PanGestureTypeForEvent(theEvent),
+                             eventIntervalTime, eventTimeStamp,
+                             position, preciseDelta, modifiers);
+    panEvent.mLineOrPageDeltaX = lineOrPageDelta.x;
+    panEvent.mLineOrPageDeltaY = lineOrPageDelta.y;
+
+    if (panEvent.mType == PanGestureInput::PANGESTURE_END) {
+      // Check if there's a momentum start event in the event queue, so that we
+      // can annotate this event.
+      NSEvent* nextWheelEvent =
+        [NSApp nextEventMatchingMask:NSScrollWheelMask
+                           untilDate:[NSDate distantPast]
+                              inMode:NSDefaultRunLoopMode
+                             dequeue:NO];
+      if (nextWheelEvent &&
+          PanGestureTypeForEvent(nextWheelEvent) == PanGestureInput::PANGESTURE_MOMENTUMSTART) {
+        panEvent.mFollowedByMomentum = true;
+      }
+    }
+
+    bool canTriggerSwipe = [self shouldConsiderStartingSwipeFromEvent:theEvent];
+    panEvent.mRequiresContentResponseIfCannotScrollHorizontallyInStartDirection = canTriggerSwipe;
+    geckoChildDeathGrip->DispatchAPZWheelInputEvent(panEvent, canTriggerSwipe);
+  } else if (usePreciseDeltas) {
+    // This is on 10.6 or old touchpads that don't have any phase information.
+    ScrollWheelInput wheelEvent(eventIntervalTime, eventTimeStamp, modifiers,
+                                ScrollWheelInput::SCROLLMODE_INSTANT,
+                                ScrollWheelInput::SCROLLDELTA_PIXEL,
+                                position,
+                                preciseDelta.x,
+                                preciseDelta.y,
+                                false);
+    wheelEvent.mLineOrPageDeltaX = lineOrPageDelta.x;
+    wheelEvent.mLineOrPageDeltaY = lineOrPageDelta.y;
+    wheelEvent.mIsMomentum = nsCocoaUtils::IsMomentumScrollEvent(theEvent);
+    geckoChildDeathGrip->DispatchAPZWheelInputEvent(wheelEvent, false);
+  } else {
+    ScrollWheelInput::ScrollMode scrollMode = ScrollWheelInput::SCROLLMODE_INSTANT;
+    if (gfxPrefs::SmoothScrollEnabled() && gfxPrefs::WheelSmoothScrollEnabled()) {
+      scrollMode = ScrollWheelInput::SCROLLMODE_SMOOTH;
+    }
+    ScrollWheelInput wheelEvent(eventIntervalTime, eventTimeStamp, modifiers,
+                                scrollMode,
+                                ScrollWheelInput::SCROLLDELTA_LINE,
+                                position,
+                                lineOrPageDelta.x,
+                                lineOrPageDelta.y,
+                                false);
+    wheelEvent.mLineOrPageDeltaX = lineOrPageDelta.x;
+    wheelEvent.mLineOrPageDeltaY = lineOrPageDelta.y;
+    geckoChildDeathGrip->DispatchAPZWheelInputEvent(wheelEvent, false);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+-(NSMenu*)menuForEvent:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if (!mGeckoChild)
+    return nil;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  [self maybeRollup:theEvent];
+  if (!mGeckoChild)
+    return nil;
+
+  // Cocoa doesn't always dispatch a mouseDown: for a control-click event,
+  // depends on what we return from menuForEvent:. Gecko always expects one
+  // and expects the mouse down event before the context menu event, so
+  // get that event sent first if this is a left mouse click.
+  if ([theEvent type] == NSLeftMouseDown) {
+    [self mouseDown:theEvent];
+    if (!mGeckoChild)
+      return nil;
+  }
+
+  WidgetMouseEvent geckoEvent(true, eContextMenu, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:theEvent toGeckoEvent:&geckoEvent];
+  geckoEvent.button = WidgetMouseEvent::eRightButton;
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+  if (!mGeckoChild)
+    return nil;
+
+  [self maybeInitContextMenuTracking];
+
+  // Go up our view chain to fetch the correct menu to return.
+  return [self contextMenu];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (NSMenu*)contextMenu
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSView* superView = [self superview];
+  if ([superView respondsToSelector:@selector(contextMenu)])
+    return [(NSView<mozView>*)superView contextMenu];
+
+  return nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void) convertCocoaMouseWheelEvent:(NSEvent*)aMouseEvent
+                        toGeckoEvent:(WidgetWheelEvent*)outWheelEvent
+{
+  [self convertCocoaMouseEvent:aMouseEvent toGeckoEvent:outWheelEvent];
+
+  bool usePreciseDeltas = nsCocoaUtils::HasPreciseScrollingDeltas(aMouseEvent) &&
+    Preferences::GetBool("mousewheel.enable_pixel_scrolling", true);
+
+  outWheelEvent->mDeltaMode =
+    usePreciseDeltas ? nsIDOMWheelEvent::DOM_DELTA_PIXEL
+                     : nsIDOMWheelEvent::DOM_DELTA_LINE;
+  outWheelEvent->mIsMomentum = nsCocoaUtils::IsMomentumScrollEvent(aMouseEvent);
+}
+
+- (void) convertCocoaMouseEvent:(NSEvent*)aMouseEvent
+                   toGeckoEvent:(WidgetInputEvent*)outGeckoEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_ASSERTION(outGeckoEvent, "convertCocoaMouseEvent:toGeckoEvent: requires non-null aoutGeckoEvent");
+  if (!outGeckoEvent)
+    return;
+
+  nsCocoaUtils::InitInputEvent(*outGeckoEvent, aMouseEvent);
+
+  // convert point to view coordinate system
+  NSPoint locationInWindow = nsCocoaUtils::EventLocationForWindow(aMouseEvent, [self window]);
+
+  outGeckoEvent->mRefPoint = [self convertWindowCoordinates:locationInWindow];
+
+  WidgetMouseEventBase* mouseEvent = outGeckoEvent->AsMouseEventBase();
+  mouseEvent->buttons = 0;
+  NSUInteger mouseButtons = [NSEvent pressedMouseButtons];
+
+  if (mouseButtons & 0x01) {
+    mouseEvent->buttons |= WidgetMouseEvent::eLeftButtonFlag;
+  }
+  if (mouseButtons & 0x02) {
+    mouseEvent->buttons |= WidgetMouseEvent::eRightButtonFlag;
+  }
+  if (mouseButtons & 0x04) {
+    mouseEvent->buttons |= WidgetMouseEvent::eMiddleButtonFlag;
+  }
+  if (mouseButtons & 0x08) {
+    mouseEvent->buttons |= WidgetMouseEvent::e4thButtonFlag;
+  }
+  if (mouseButtons & 0x10) {
+    mouseEvent->buttons |= WidgetMouseEvent::e5thButtonFlag;
+  }
+
+  switch ([aMouseEvent type]) {
+    case NSLeftMouseDown:
+    case NSLeftMouseUp:
+    case NSLeftMouseDragged:
+    case NSRightMouseDown:
+    case NSRightMouseUp:
+    case NSRightMouseDragged:
+    case NSOtherMouseDown:
+    case NSOtherMouseUp:
+    case NSOtherMouseDragged:
+      if ([aMouseEvent subtype] == NSTabletPointEventSubtype) {
+        mouseEvent->pressure = [aMouseEvent pressure];
+        MOZ_ASSERT(mouseEvent->pressure >= 0.0 && mouseEvent->pressure <= 1.0);
+      }
+      break;
+
+    default:
+      // Don't check other NSEvents for pressure.
+      break;
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (BOOL)shouldZoomOnDoubleClick
+{
+  if ([NSWindow respondsToSelector:@selector(_shouldZoomOnDoubleClick)]) {
+    return [NSWindow _shouldZoomOnDoubleClick];
+  }
+  return nsCocoaFeatures::OnYosemiteOrLater();
+}
+
+- (BOOL)shouldMinimizeOnTitlebarDoubleClick
+{
+  NSString *MDAppleMiniaturizeOnDoubleClickKey =
+                                      @"AppleMiniaturizeOnDoubleClick";
+  NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
+  bool shouldMinimize = [[userDefaults
+          objectForKey:MDAppleMiniaturizeOnDoubleClickKey] boolValue];
+
+  return shouldMinimize;
+}
+
+#pragma mark -
+// NSTextInputClient implementation
+
+- (NSRange)markedRange
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NS_ENSURE_TRUE(mTextInputHandler, NSMakeRange(NSNotFound, 0));
+  return mTextInputHandler->MarkedRange();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSMakeRange(0, 0));
+}
+
+- (NSRange)selectedRange
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NS_ENSURE_TRUE(mTextInputHandler, NSMakeRange(NSNotFound, 0));
+  return mTextInputHandler->SelectedRange();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSMakeRange(0, 0));
+}
+
+- (BOOL)drawsVerticallyForCharacterAtIndex:(NSUInteger)charIndex
+{
+  NS_ENSURE_TRUE(mTextInputHandler, NO);
+  if (charIndex == NSNotFound) {
+    return NO;
+  }
+  return mTextInputHandler->DrawsVerticallyForCharacterAtIndex(charIndex);
+}
+
+- (NSUInteger)characterIndexForPoint:(NSPoint)thePoint
+{
+  NS_ENSURE_TRUE(mTextInputHandler, 0);
+  return mTextInputHandler->CharacterIndexForPoint(thePoint);
+}
+
+- (NSArray*)validAttributesForMarkedText
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NS_ENSURE_TRUE(mTextInputHandler, [NSArray array]);
+  return mTextInputHandler->GetValidAttributesForMarkedText();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)insertText:(id)aString replacementRange:(NSRange)replacementRange
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_ENSURE_TRUE_VOID(mGeckoChild);
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  NSAttributedString* attrStr;
+  if ([aString isKindOfClass:[NSAttributedString class]]) {
+    attrStr = static_cast<NSAttributedString*>(aString);
+  } else {
+    attrStr = [[[NSAttributedString alloc] initWithString:aString] autorelease];
+  }
+
+  mTextInputHandler->InsertText(attrStr, &replacementRange);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)doCommandBySelector:(SEL)aSelector
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mGeckoChild || !mTextInputHandler) {
+    return;
+  }
+
+  const char* sel = reinterpret_cast<const char*>(aSelector);
+  if (!mTextInputHandler->DoCommandBySelector(sel)) {
+    [super doCommandBySelector:aSelector];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)unmarkText
+{
+  NS_ENSURE_TRUE_VOID(mTextInputHandler);
+  mTextInputHandler->CommitIMEComposition();
+}
+
+- (BOOL) hasMarkedText
+{
+  NS_ENSURE_TRUE(mTextInputHandler, NO);
+  return mTextInputHandler->HasMarkedText();
+}
+
+- (void)setMarkedText:(id)aString selectedRange:(NSRange)selectedRange
+                               replacementRange:(NSRange)replacementRange
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_ENSURE_TRUE_VOID(mTextInputHandler);
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  NSAttributedString* attrStr;
+  if ([aString isKindOfClass:[NSAttributedString class]]) {
+    attrStr = static_cast<NSAttributedString*>(aString);
+  } else {
+    attrStr = [[[NSAttributedString alloc] initWithString:aString] autorelease];
+  }
+
+  mTextInputHandler->SetMarkedText(attrStr, selectedRange, &replacementRange);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (NSAttributedString*)attributedSubstringForProposedRange:(NSRange)aRange
+                                        actualRange:(NSRangePointer)actualRange
+{
+  NS_ENSURE_TRUE(mTextInputHandler, nil);
+  return mTextInputHandler->GetAttributedSubstringFromRange(aRange,
+                                                            actualRange);
+}
+
+- (NSRect)firstRectForCharacterRange:(NSRange)aRange
+                         actualRange:(NSRangePointer)actualRange
+{
+  NS_ENSURE_TRUE(mTextInputHandler, NSMakeRect(0.0, 0.0, 0.0, 0.0));
+  return mTextInputHandler->FirstRectForCharacterRange(aRange, actualRange);
+}
+
+- (void)quickLookWithEvent:(NSEvent*)event
+{
+  // Show dictionary by current point
+  WidgetContentCommandEvent
+    contentCommandEvent(true, eContentCommandLookUpDictionary, mGeckoChild);
+  NSPoint point = [self convertPoint:[event locationInWindow] fromView:nil];
+  contentCommandEvent.mRefPoint = mGeckoChild->CocoaPointsToDevPixels(point);
+  mGeckoChild->DispatchWindowEvent(contentCommandEvent);
+  // The widget might have been destroyed.
+}
+
+- (NSInteger)windowLevel
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NS_ENSURE_TRUE(mTextInputHandler, [[self window] level]);
+  return mTextInputHandler->GetWindowLevel();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSNormalWindowLevel);
+}
+
+#pragma mark -
+
+// This is a private API that Cocoa uses.
+// Cocoa will call this after the menu system returns "NO" for "performKeyEquivalent:".
+// We want all they key events we can get so just return YES. In particular, this fixes
+// ctrl-tab - we don't get a "keyDown:" call for that without this.
+- (BOOL)_wantsKeyDownForEvent:(NSEvent*)event
+{
+  return YES;
+}
+
+- (NSEvent*)lastKeyDownEvent
+{
+  return mLastKeyDownEvent;
+}
+
+- (void)keyDown:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mLastKeyDownEvent release];
+  mLastKeyDownEvent = [theEvent retain];
+
+  // Weird things can happen on keyboard input if the key window isn't in the
+  // current space.  For example see bug 1056251.  To get around this, always
+  // make sure that, if our window is key, it's also made frontmost.  Doing
+  // this automatically switches to whatever space our window is in.  Safari
+  // does something similar.  Our window should normally always be key --
+  // otherwise why is the OS sending us a key down event?  But it's just
+  // possible we're in Gecko's hidden window, so we check first.
+  NSWindow *viewWindow = [self window];
+  if (viewWindow && [viewWindow isKeyWindow]) {
+    [viewWindow orderWindow:NSWindowAbove relativeTo:0];
+  }
+
+#if !defined(RELEASE_OR_BETA) || defined(DEBUG)
+  if (!Preferences::GetBool("intl.allow-insecure-text-input", false) &&
+      mGeckoChild && mTextInputHandler && mTextInputHandler->IsFocused()) {
+    if (mGeckoChild->GetInputContext().IsPasswordEditor() &&
+               !TextInputHandler::IsSecureEventInputEnabled()) {
+      #define CRASH_MESSAGE "A password editor has focus, but not in secure input mode"
+      MOZ_CRASH(CRASH_MESSAGE);
+      #undef CRASH_MESSAGE
+    } else if (!mGeckoChild->GetInputContext().IsPasswordEditor() &&
+               TextInputHandler::IsSecureEventInputEnabled()) {
+      #define CRASH_MESSAGE "A non-password editor has focus, but in secure input mode"
+      MOZ_CRASH(CRASH_MESSAGE);
+      #undef CRASH_MESSAGE
+    }
+  }
+#endif // #if !defined(RELEASE_OR_BETA) || defined(DEBUG)
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  bool handled = false;
+  if (mGeckoChild && mTextInputHandler) {
+    handled = mTextInputHandler->HandleKeyDownEvent(theEvent);
+  }
+
+  // We always allow keyboard events to propagate to keyDown: but if they are not
+  // handled we give special Application menu items a chance to act.
+  if (!handled && sApplicationMenu) {
+    [sApplicationMenu performKeyEquivalent:theEvent];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)keyUp:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_ENSURE_TRUE(mGeckoChild, );
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  mTextInputHandler->HandleKeyUpEvent(theEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)insertNewline:(id)sender
+{
+  if (mTextInputHandler) {
+    NSAttributedString *attrStr = [[NSAttributedString alloc] initWithString:@"\n"];
+    mTextInputHandler->InsertText(attrStr);
+    [attrStr release];
+  }
+}
+
+- (void)flagsChanged:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NS_ENSURE_TRUE(mGeckoChild, );
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  mTextInputHandler->HandleFlagsChanged(theEvent);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (BOOL) isFirstResponder
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NSResponder* resp = [[self window] firstResponder];
+  return (resp == (NSResponder*)self);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+- (BOOL)isDragInProgress
+{
+  if (!mDragService)
+    return NO;
+
+  nsCOMPtr<nsIDragSession> dragSession;
+  mDragService->GetCurrentSession(getter_AddRefs(dragSession));
+  return dragSession != nullptr;
+}
+
+- (BOOL)inactiveWindowAcceptsMouseEvent:(NSEvent*)aEvent
+{
+  // If we're being destroyed assume the default -- return YES.
+  if (!mGeckoChild)
+    return YES;
+
+  WidgetMouseEvent geckoEvent(true, eMouseActivate, mGeckoChild,
+                              WidgetMouseEvent::eReal);
+  [self convertCocoaMouseEvent:aEvent toGeckoEvent:&geckoEvent];
+  return (mGeckoChild->DispatchInputEvent(&geckoEvent) != nsEventStatus_eConsumeNoDefault);
+}
+
+// We must always call through to our superclass, even when mGeckoChild is
+// nil -- otherwise the keyboard focus can end up in the wrong NSView.
+- (BOOL)becomeFirstResponder
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return [super becomeFirstResponder];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(YES);
+}
+
+- (void)viewsWindowDidBecomeKey
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mGeckoChild)
+    return;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  // check to see if the window implements the mozWindow protocol. This
+  // allows embedders to avoid re-entrant calls to -makeKeyAndOrderFront,
+  // which can happen because these activate calls propagate out
+  // to the embedder via nsIEmbeddingSiteWindow::SetFocus().
+  BOOL isMozWindow = [[self window] respondsToSelector:@selector(setSuppressMakeKeyFront:)];
+  if (isMozWindow)
+    [[self window] setSuppressMakeKeyFront:YES];
+
+  nsIWidgetListener* listener = mGeckoChild->GetWidgetListener();
+  if (listener)
+    listener->WindowActivated();
+
+  if (isMozWindow)
+    [[self window] setSuppressMakeKeyFront:NO];
+
+  if (mGeckoChild->GetInputContext().IsPasswordEditor()) {
+    TextInputHandler::EnableSecureEventInput();
+  } else {
+    TextInputHandler::EnsureSecureEventInputDisabled();
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)viewsWindowDidResignKey
+{
+  if (!mGeckoChild)
+    return;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  nsIWidgetListener* listener = mGeckoChild->GetWidgetListener();
+  if (listener)
+    listener->WindowDeactivated();
+
+  TextInputHandler::EnsureSecureEventInputDisabled();
+}
+
+// If the call to removeFromSuperview isn't delayed from nsChildView::
+// TearDownView(), the NSView hierarchy might get changed during calls to
+// [ChildView drawRect:], which leads to "beyond bounds" exceptions in
+// NSCFArray.  For more info see bmo bug 373122.  Apple's docs claim that
+// removeFromSuperviewWithoutNeedingDisplay "can be safely invoked during
+// display" (whatever "display" means).  But it's _not_ true that it can be
+// safely invoked during calls to [NSView drawRect:].  We use
+// removeFromSuperview here because there's no longer any danger of being
+// "invoked during display", and because doing do clears up bmo bug 384343.
+- (void)delayedTearDown
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [self removeFromSuperview];
+  [self release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+#pragma mark -
+
+// drag'n'drop stuff
+#define kDragServiceContractID "@mozilla.org/widget/dragservice;1"
+
+- (NSDragOperation)dragOperationFromDragAction:(int32_t)aDragAction
+{
+  if (nsIDragService::DRAGDROP_ACTION_LINK & aDragAction)
+    return NSDragOperationLink;
+  if (nsIDragService::DRAGDROP_ACTION_COPY & aDragAction)
+    return NSDragOperationCopy;
+  if (nsIDragService::DRAGDROP_ACTION_MOVE & aDragAction)
+    return NSDragOperationGeneric;
+  return NSDragOperationNone;
+}
+
+- (LayoutDeviceIntPoint)convertWindowCoordinates:(NSPoint)aPoint
+{
+  if (!mGeckoChild) {
+    return LayoutDeviceIntPoint(0, 0);
+  }
+
+  NSPoint localPoint = [self convertPoint:aPoint fromView:nil];
+  return mGeckoChild->CocoaPointsToDevPixels(localPoint);
+}
+
+- (LayoutDeviceIntPoint)convertWindowCoordinatesRoundDown:(NSPoint)aPoint
+{
+  if (!mGeckoChild) {
+    return LayoutDeviceIntPoint(0, 0);
+  }
+
+  NSPoint localPoint = [self convertPoint:aPoint fromView:nil];
+  return mGeckoChild->CocoaPointsToDevPixelsRoundDown(localPoint);
+}
+
+// This is a utility function used by NSView drag event methods
+// to send events. It contains all of the logic needed for Gecko
+// dragging to work. Returns the appropriate cocoa drag operation code.
+- (NSDragOperation)doDragAction:(EventMessage)aMessage sender:(id)aSender
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (!mGeckoChild)
+    return NSDragOperationNone;
+
+  MOZ_LOG(sCocoaLog, LogLevel::Info, ("ChildView doDragAction: entered\n"));
+
+  if (!mDragService) {
+    CallGetService(kDragServiceContractID, &mDragService);
+    NS_ASSERTION(mDragService, "Couldn't get a drag service - big problem!");
+    if (!mDragService)
+      return NSDragOperationNone;
+  }
+
+  if (aMessage == eDragEnter) {
+    mDragService->StartDragSession();
+  }
+
+  nsCOMPtr<nsIDragSession> dragSession;
+  mDragService->GetCurrentSession(getter_AddRefs(dragSession));
+  if (dragSession) {
+    if (aMessage == eDragOver) {
+      // fire the drag event at the source. Just ignore whether it was
+      // cancelled or not as there isn't actually a means to stop the drag
+      mDragService->FireDragEventAtSource(eDrag);
+      dragSession->SetCanDrop(false);
+    } else if (aMessage == eDrop) {
+      // We make the assumption that the dragOver handlers have correctly set
+      // the |canDrop| property of the Drag Session.
+      bool canDrop = false;
+      if (!NS_SUCCEEDED(dragSession->GetCanDrop(&canDrop)) || !canDrop) {
+        [self doDragAction:eDragExit sender:aSender];
+
+        nsCOMPtr<nsIDOMNode> sourceNode;
+        dragSession->GetSourceNode(getter_AddRefs(sourceNode));
+        if (!sourceNode) {
+          mDragService->EndDragSession(false);
+        }
+        return NSDragOperationNone;
+      }
+    }
+
+    unsigned int modifierFlags = [[NSApp currentEvent] modifierFlags];
+    uint32_t action = nsIDragService::DRAGDROP_ACTION_MOVE;
+    // force copy = option, alias = cmd-option, default is move
+    if (modifierFlags & NSAlternateKeyMask) {
+      if (modifierFlags & NSCommandKeyMask)
+        action = nsIDragService::DRAGDROP_ACTION_LINK;
+      else
+        action = nsIDragService::DRAGDROP_ACTION_COPY;
+    }
+    dragSession->SetDragAction(action);
+  }
+
+  // set up gecko event
+  WidgetDragEvent geckoEvent(true, aMessage, mGeckoChild);
+  nsCocoaUtils::InitInputEvent(geckoEvent, [NSApp currentEvent]);
+
+  // Use our own coordinates in the gecko event.
+  // Convert event from gecko global coords to gecko view coords.
+  NSPoint draggingLoc = [aSender draggingLocation];
+
+  geckoEvent.mRefPoint = [self convertWindowCoordinates:draggingLoc];
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  mGeckoChild->DispatchInputEvent(&geckoEvent);
+  if (!mGeckoChild)
+    return NSDragOperationNone;
+
+  if (dragSession) {
+    switch (aMessage) {
+      case eDragEnter:
+      case eDragOver: {
+        uint32_t dragAction;
+        dragSession->GetDragAction(&dragAction);
+
+        // If TakeChildProcessDragAction returns something other than
+        // DRAGDROP_ACTION_UNINITIALIZED, it means that the last event was sent
+        // to the child process and this event is also being sent to the child
+        // process. In this case, use the last event's action instead.
+        nsDragService* dragService = static_cast<nsDragService *>(mDragService);
+        int32_t childDragAction = dragService->TakeChildProcessDragAction();
+        if (childDragAction != nsIDragService::DRAGDROP_ACTION_UNINITIALIZED) {
+          dragAction = childDragAction;
+        }
+
+        return [self dragOperationFromDragAction:dragAction];
+      }
+      case eDragExit:
+      case eDrop: {
+        nsCOMPtr<nsIDOMNode> sourceNode;
+        dragSession->GetSourceNode(getter_AddRefs(sourceNode));
+        if (!sourceNode) {
+          // We're leaving a window while doing a drag that was
+          // initiated in a different app. End the drag session,
+          // since we're done with it for now (until the user
+          // drags back into mozilla).
+          mDragService->EndDragSession(false);
+        }
+      }
+      default:
+        break;
+    }
+  }
+
+  return NSDragOperationGeneric;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSDragOperationNone);
+}
+
+- (NSDragOperation)draggingEntered:(id <NSDraggingInfo>)sender
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  MOZ_LOG(sCocoaLog, LogLevel::Info, ("ChildView draggingEntered: entered\n"));
+
+  // there should never be a globalDragPboard when "draggingEntered:" is
+  // called, but just in case we'll take care of it here.
+  [globalDragPboard release];
+
+  // Set the global drag pasteboard that will be used for this drag session.
+  // This will be set back to nil when the drag session ends (mouse exits
+  // the view or a drop happens within the view).
+  globalDragPboard = [[sender draggingPasteboard] retain];
+
+  return [self doDragAction:eDragEnter sender:sender];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSDragOperationNone);
+}
+
+- (NSDragOperation)draggingUpdated:(id <NSDraggingInfo>)sender
+{
+  MOZ_LOG(sCocoaLog, LogLevel::Info, ("ChildView draggingUpdated: entered\n"));
+
+  return [self doDragAction:eDragOver sender:sender];
+}
+
+- (void)draggingExited:(id <NSDraggingInfo>)sender
+{
+  MOZ_LOG(sCocoaLog, LogLevel::Info, ("ChildView draggingExited: entered\n"));
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  [self doDragAction:eDragExit sender:sender];
+  NS_IF_RELEASE(mDragService);
+}
+
+- (BOOL)performDragOperation:(id <NSDraggingInfo>)sender
+{
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  BOOL handled = [self doDragAction:eDrop sender:sender] != NSDragOperationNone;
+  NS_IF_RELEASE(mDragService);
+  return handled;
+}
+
+// NSDraggingSource
+- (void)draggedImage:(NSImage *)anImage movedTo:(NSPoint)aPoint
+{
+  // Get the drag service if it isn't already cached. The drag service
+  // isn't cached when dragging over a different application.
+  nsCOMPtr<nsIDragService> dragService = mDragService;
+  if (!dragService) {
+    dragService = do_GetService(kDragServiceContractID);
+  }
+
+  if (dragService) {
+    NSPoint pnt = [NSEvent mouseLocation];
+    FlipCocoaScreenCoordinate(pnt);
+
+    LayoutDeviceIntPoint devPoint = mGeckoChild->CocoaPointsToDevPixels(pnt);
+    dragService->DragMoved(devPoint.x, devPoint.y);
+  }
+}
+
+// NSDraggingSource
+- (void)draggedImage:(NSImage *)anImage endedAt:(NSPoint)aPoint operation:(NSDragOperation)operation
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  gDraggedTransferables = nullptr;
+
+  NSEvent *currentEvent = [NSApp currentEvent];
+  gUserCancelledDrag = ([currentEvent type] == NSKeyDown &&
+                        [currentEvent keyCode] == kVK_Escape);
+
+  if (!mDragService) {
+    CallGetService(kDragServiceContractID, &mDragService);
+    NS_ASSERTION(mDragService, "Couldn't get a drag service - big problem!");
+  }
+
+  if (mDragService) {
+    // set the dragend point from the current mouse location
+    nsDragService* dragService = static_cast<nsDragService *>(mDragService);
+    NSPoint pnt = [NSEvent mouseLocation];
+    FlipCocoaScreenCoordinate(pnt);
+    dragService->SetDragEndPoint(gfx::IntPoint::Round(pnt.x, pnt.y));
+
+    // XXX: dropEffect should be updated per |operation|.
+    // As things stand though, |operation| isn't well handled within "our"
+    // events, that is, when the drop happens within the window: it is set
+    // either to NSDragOperationGeneric or to NSDragOperationNone.
+    // For that reason, it's not yet possible to override dropEffect per the
+    // given OS value, and it's also unclear what's the correct dropEffect
+    // value for NSDragOperationGeneric that is passed by other applications.
+    // All that said, NSDragOperationNone is still reliable.
+    if (operation == NSDragOperationNone) {
+      nsCOMPtr<nsIDOMDataTransfer> dataTransfer;
+      dragService->GetDataTransfer(getter_AddRefs(dataTransfer));
+      if (dataTransfer)
+        dataTransfer->SetDropEffectInt(nsIDragService::DRAGDROP_ACTION_NONE);
+    }
+
+    mDragService->EndDragSession(true);
+    NS_RELEASE(mDragService);
+  }
+
+  [globalDragPboard release];
+  globalDragPboard = nil;
+  [gLastDragMouseDownEvent release];
+  gLastDragMouseDownEvent = nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// NSDraggingSource
+// this is just implemented so we comply with the NSDraggingSource informal protocol
+- (NSDragOperation)draggingSourceOperationMaskForLocal:(BOOL)isLocal
+{
+  return UINT_MAX;
+}
+
+// This method is a callback typically invoked in response to a drag ending on the desktop
+// or a Findow folder window; the argument passed is a path to the drop location, to be used
+// in constructing a complete pathname for the file(s) we want to create as a result of
+// the drag.
+- (NSArray *)namesOfPromisedFilesDroppedAtDestination:(NSURL*)dropDestination
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  nsresult rv;
+
+  MOZ_LOG(sCocoaLog, LogLevel::Info, ("ChildView namesOfPromisedFilesDroppedAtDestination: entering callback for promised files\n"));
+
+  nsCOMPtr<nsIFile> targFile;
+  NS_NewLocalFile(EmptyString(), true, getter_AddRefs(targFile));
+  nsCOMPtr<nsILocalFileMac> macLocalFile = do_QueryInterface(targFile);
+  if (!macLocalFile) {
+    NS_ERROR("No Mac local file");
+    return nil;
+  }
+
+  if (!NS_SUCCEEDED(macLocalFile->InitWithCFURL((CFURLRef)dropDestination))) {
+    NS_ERROR("failed InitWithCFURL");
+    return nil;
+  }
+
+  if (!gDraggedTransferables)
+    return nil;
+
+  uint32_t transferableCount;
+  rv = gDraggedTransferables->GetLength(&transferableCount);
+  if (NS_FAILED(rv))
+    return nil;
+
+  for (uint32_t i = 0; i < transferableCount; i++) {
+    nsCOMPtr<nsITransferable> item = do_QueryElementAt(gDraggedTransferables, i);
+    if (!item) {
+      NS_ERROR("no transferable");
+      return nil;
+    }
+
+    item->SetTransferData(kFilePromiseDirectoryMime, macLocalFile, sizeof(nsIFile*));
+
+    // now request the kFilePromiseMime data, which will invoke the data provider
+    // If successful, the returned data is a reference to the resulting file.
+    nsCOMPtr<nsISupports> fileDataPrimitive;
+    uint32_t dataSize = 0;
+    item->GetTransferData(kFilePromiseMime, getter_AddRefs(fileDataPrimitive), &dataSize);
+  }
+
+  NSPasteboard* generalPboard = [NSPasteboard pasteboardWithName:NSDragPboard];
+  NSData* data = [generalPboard dataForType:@"application/x-moz-file-promise-dest-filename"];
+  NSString* name = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
+  NSArray* rslt = [NSArray arrayWithObject:name];
+
+  [name release];
+
+  return rslt;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+#pragma mark -
+
+// Support for the "Services" menu. We currently only support sending strings
+// and HTML to system services.
+
+- (id)validRequestorForSendType:(NSString *)sendType
+                     returnType:(NSString *)returnType
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  // sendType contains the type of data that the service would like this
+  // application to send to it.  sendType is nil if the service is not
+  // requesting any data.
+  //
+  // returnType contains the type of data the the service would like to
+  // return to this application (e.g., to overwrite the selection).
+  // returnType is nil if the service will not return any data.
+  //
+  // The following condition thus triggers when the service expects a string
+  // or HTML from us or no data at all AND when the service will either not
+  // send back any data to us or will send a string or HTML back to us.
+
+#define IsSupportedType(typeStr) ([typeStr isEqual:NSStringPboardType] || [typeStr isEqual:NSHTMLPboardType])
+
+  id result = nil;
+
+  if ((!sendType || IsSupportedType(sendType)) &&
+      (!returnType || IsSupportedType(returnType))) {
+    if (mGeckoChild) {
+      // Assume that this object will be able to handle this request.
+      result = self;
+
+      // Keep the ChildView alive during this operation.
+      nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+      if (sendType) {
+        // Determine if there is a current selection (chrome/content).
+        if (!nsClipboard::sSelectionCache) {
+          result = nil;
+        }
+      }
+
+      // Determine if we can paste (if receiving data from the service).
+      if (mGeckoChild && returnType) {
+        WidgetContentCommandEvent command(true,
+                                          eContentCommandPasteTransferable,
+                                          mGeckoChild, true);
+        // This might possibly destroy our widget (and null out mGeckoChild).
+        mGeckoChild->DispatchWindowEvent(command);
+        if (!mGeckoChild || !command.mSucceeded || !command.mIsEnabled)
+          result = nil;
+      }
+    }
+  }
+
+#undef IsSupportedType
+
+  // Give the superclass a chance if this object will not handle this request.
+  if (!result)
+    result = [super validRequestorForSendType:sendType returnType:returnType];
+
+  return result;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (BOOL)writeSelectionToPasteboard:(NSPasteboard *)pboard
+                             types:(NSArray *)types
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+
+  // Make sure that the service will accept strings or HTML.
+  if ([types containsObject:NSStringPboardType] == NO &&
+      [types containsObject:NSHTMLPboardType] == NO)
+    return NO;
+
+  // Bail out if there is no Gecko object.
+  if (!mGeckoChild)
+    return NO;
+
+  // Transform the transferable to an NSDictionary.
+  NSDictionary* pasteboardOutputDict = nullptr;
+
+  pasteboardOutputDict = nsClipboard::
+      PasteboardDictFromTransferable(nsClipboard::sSelectionCache);
+
+  if (!pasteboardOutputDict)
+    return NO;
+
+  // Declare the pasteboard types.
+  unsigned int typeCount = [pasteboardOutputDict count];
+  NSMutableArray* declaredTypes = [NSMutableArray arrayWithCapacity:typeCount];
+  [declaredTypes addObjectsFromArray:[pasteboardOutputDict allKeys]];
+  [pboard declareTypes:declaredTypes owner:nil];
+
+  // Write the data to the pasteboard.
+  for (unsigned int i = 0; i < typeCount; i++) {
+    NSString* currentKey = [declaredTypes objectAtIndex:i];
+    id currentValue = [pasteboardOutputDict valueForKey:currentKey];
+
+    if (currentKey == NSStringPboardType ||
+        currentKey == kCorePboardType_url ||
+        currentKey == kCorePboardType_urld ||
+        currentKey == kCorePboardType_urln) {
+      [pboard setString:currentValue forType:currentKey];
+    } else if (currentKey == NSHTMLPboardType) {
+      [pboard setString:(nsClipboard::WrapHtmlForSystemPasteboard(currentValue)) forType:currentKey];
+    } else if (currentKey == NSTIFFPboardType) {
+      [pboard setData:currentValue forType:currentKey];
+    } else if (currentKey == NSFilesPromisePboardType) {
+      [pboard setPropertyList:currentValue forType:currentKey];
+    }
+  }
+
+  return YES;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+// Called if the service wants us to replace the current selection.
+- (BOOL)readSelectionFromPasteboard:(NSPasteboard *)pboard
+{
+  nsresult rv;
+  nsCOMPtr<nsITransferable> trans = do_CreateInstance("@mozilla.org/widget/transferable;1", &rv);
+  if (NS_FAILED(rv))
+    return NO;
+  trans->Init(nullptr);
+
+  trans->AddDataFlavor(kUnicodeMime);
+  trans->AddDataFlavor(kHTMLMime);
+
+  rv = nsClipboard::TransferableFromPasteboard(trans, pboard);
+  if (NS_FAILED(rv))
+    return NO;
+
+  NS_ENSURE_TRUE(mGeckoChild, false);
+
+  WidgetContentCommandEvent command(true,
+                                    eContentCommandPasteTransferable,
+                                    mGeckoChild);
+  command.mTransferable = trans;
+  mGeckoChild->DispatchWindowEvent(command);
+
+  return command.mSucceeded && command.mIsEnabled;
+}
+
+NS_IMETHODIMP
+nsChildView::GetSelectionAsPlaintext(nsAString& aResult)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!nsClipboard::sSelectionCache) {
+    MOZ_ASSERT(aResult.IsEmpty());
+    return NS_OK;
+  }
+
+  // Get the current chrome or content selection.
+  NSDictionary* pasteboardOutputDict = nullptr;
+  pasteboardOutputDict = nsClipboard::
+    PasteboardDictFromTransferable(nsClipboard::sSelectionCache);
+
+  if (NS_WARN_IF(!pasteboardOutputDict)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // Declare the pasteboard types.
+  unsigned int typeCount = [pasteboardOutputDict count];
+  NSMutableArray* declaredTypes = [NSMutableArray arrayWithCapacity:typeCount];
+  [declaredTypes addObjectsFromArray:[pasteboardOutputDict allKeys]];
+  NSString* currentKey = [declaredTypes objectAtIndex:0];
+  NSString* currentValue = [pasteboardOutputDict valueForKey:currentKey];
+  const char* textSelection = [currentValue UTF8String];
+  aResult = NS_ConvertUTF8toUTF16(textSelection);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+#pragma mark -
+
+#ifdef ACCESSIBILITY
+
+/* Every ChildView has a corresponding mozDocAccessible object that is doing all
+   the heavy lifting. The topmost ChildView corresponds to a mozRootAccessible
+   object.
+
+   All ChildView needs to do is to route all accessibility calls (from the NSAccessibility APIs)
+   down to its object, pretending that they are the same.
+*/
+- (id<mozAccessible>)accessible
+{
+  if (!mGeckoChild)
+    return nil;
+
+  id<mozAccessible> nativeAccessible = nil;
+
+  nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  RefPtr<nsChildView> geckoChild(mGeckoChild);
+  RefPtr<a11y::Accessible> accessible = geckoChild->GetDocumentAccessible();
+  if (!accessible)
+    return nil;
+
+  accessible->GetNativeInterface((void**)&nativeAccessible);
+
+#ifdef DEBUG_hakan
+  NSAssert(![nativeAccessible isExpired], @"native acc is expired!!!");
+#endif
+
+  return nativeAccessible;
+}
+
+/* Implementation of formal mozAccessible formal protocol (enabling mozViews
+   to talk to mozAccessible objects in the accessibility module). */
+
+- (BOOL)hasRepresentedView
+{
+  return YES;
+}
+
+- (id)representedView
+{
+  return self;
+}
+
+- (BOOL)isRoot
+{
+  return [[self accessible] isRoot];
+}
+
+#ifdef DEBUG
+- (void)printHierarchy
+{
+  [[self accessible] printHierarchy];
+}
+#endif
+
+#pragma mark -
+
+// general
+
+- (BOOL)accessibilityIsIgnored
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityIsIgnored];
+
+  return [[self accessible] accessibilityIsIgnored];
+}
+
+- (id)accessibilityHitTest:(NSPoint)point
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityHitTest:point];
+
+  return [[self accessible] accessibilityHitTest:point];
+}
+
+- (id)accessibilityFocusedUIElement
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityFocusedUIElement];
+
+  return [[self accessible] accessibilityFocusedUIElement];
+}
+
+// actions
+
+- (NSArray*)accessibilityActionNames
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityActionNames];
+
+  return [[self accessible] accessibilityActionNames];
+}
+
+- (NSString*)accessibilityActionDescription:(NSString*)action
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityActionDescription:action];
+
+  return [[self accessible] accessibilityActionDescription:action];
+}
+
+- (void)accessibilityPerformAction:(NSString*)action
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityPerformAction:action];
+
+  return [[self accessible] accessibilityPerformAction:action];
+}
+
+// attributes
+
+- (NSArray*)accessibilityAttributeNames
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityAttributeNames];
+
+  return [[self accessible] accessibilityAttributeNames];
+}
+
+- (BOOL)accessibilityIsAttributeSettable:(NSString*)attribute
+{
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityIsAttributeSettable:attribute];
+
+  return [[self accessible] accessibilityIsAttributeSettable:attribute];
+}
+
+- (id)accessibilityAttributeValue:(NSString*)attribute
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if (!mozilla::a11y::ShouldA11yBeEnabled())
+    return [super accessibilityAttributeValue:attribute];
+
+  id<mozAccessible> accessible = [self accessible];
+
+  // if we're the root (topmost) accessible, we need to return our native AXParent as we
+  // traverse outside to the hierarchy of whoever embeds us. thus, fall back on NSView's
+  // default implementation for this attribute.
+  if ([attribute isEqualToString:NSAccessibilityParentAttribute] && [accessible isRoot]) {
+    id parentAccessible = [super accessibilityAttributeValue:attribute];
+    return parentAccessible;
+  }
+
+  return [accessible accessibilityAttributeValue:attribute];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+#endif /* ACCESSIBILITY */
+
+@end
+
+@implementation PixelHostingView
+
+- (BOOL)isFlipped {
+  return YES;
+}
+
+- (NSView*)hitTest:(NSPoint)aPoint {
+  return nil;
+}
+
+- (void)drawRect:(NSRect)aRect {
+  [(ChildView*)[self superview] doDrawRect:aRect];
+}
+
+- (BOOL)wantsBestResolutionOpenGLSurface {
+  return nsCocoaUtils::HiDPIEnabled() ? YES : NO;
+}
+
+@end
+
+#pragma mark -
+
+void
+ChildViewMouseTracker::OnDestroyView(ChildView* aView)
+{
+  if (sLastMouseEventView == aView) {
+    sLastMouseEventView = nil;
+    [sLastMouseMoveEvent release];
+    sLastMouseMoveEvent = nil;
+  }
+}
+
+void
+ChildViewMouseTracker::OnDestroyWindow(NSWindow* aWindow)
+{
+  if (sWindowUnderMouse == aWindow) {
+    sWindowUnderMouse = nil;
+  }
+}
+
+void
+ChildViewMouseTracker::MouseEnteredWindow(NSEvent* aEvent)
+{
+  sWindowUnderMouse = [aEvent window];
+  ReEvaluateMouseEnterState(aEvent);
+}
+
+void
+ChildViewMouseTracker::MouseExitedWindow(NSEvent* aEvent)
+{
+  if (sWindowUnderMouse == [aEvent window]) {
+    sWindowUnderMouse = nil;
+    ReEvaluateMouseEnterState(aEvent);
+  }
+}
+
+void
+ChildViewMouseTracker::ReEvaluateMouseEnterState(NSEvent* aEvent, ChildView* aOldView)
+{
+  ChildView* oldView = aOldView ? aOldView : sLastMouseEventView;
+  sLastMouseEventView = ViewForEvent(aEvent);
+  if (sLastMouseEventView != oldView) {
+    // Send enter and / or exit events.
+    WidgetMouseEvent::ExitFrom exitFrom =
+      [sLastMouseEventView window] == [oldView window] ?
+        WidgetMouseEvent::eChild : WidgetMouseEvent::eTopLevel;
+    [oldView sendMouseEnterOrExitEvent:aEvent
+                                 enter:NO
+                              exitFrom:exitFrom];
+    // After the cursor exits the window set it to a visible regular arrow cursor.
+    if (exitFrom == WidgetMouseEvent::eTopLevel) {
+      [[nsCursorManager sharedInstance] setCursor:eCursor_standard];
+    }
+    [sLastMouseEventView sendMouseEnterOrExitEvent:aEvent
+                                             enter:YES
+                                          exitFrom:exitFrom];
+  }
+}
+
+void
+ChildViewMouseTracker::ResendLastMouseMoveEvent()
+{
+  if (sLastMouseMoveEvent) {
+    MouseMoved(sLastMouseMoveEvent);
+  }
+}
+
+void
+ChildViewMouseTracker::MouseMoved(NSEvent* aEvent)
+{
+  MouseEnteredWindow(aEvent);
+  [sLastMouseEventView handleMouseMoved:aEvent];
+  if (sLastMouseMoveEvent != aEvent) {
+    [sLastMouseMoveEvent release];
+    sLastMouseMoveEvent = [aEvent retain];
+  }
+}
+
+void
+ChildViewMouseTracker::MouseScrolled(NSEvent* aEvent)
+{
+  if (!nsCocoaUtils::IsMomentumScrollEvent(aEvent)) {
+    // Store the position so we can pin future momentum scroll events.
+    sLastScrollEventScreenLocation = nsCocoaUtils::ScreenLocationForEvent(aEvent);
+  }
+}
+
+ChildView*
+ChildViewMouseTracker::ViewForEvent(NSEvent* aEvent)
+{
+  NSWindow* window = sWindowUnderMouse;
+  if (!window)
+    return nil;
+
+  NSPoint windowEventLocation = nsCocoaUtils::EventLocationForWindow(aEvent, window);
+  NSView* view = [[[window contentView] superview] hitTest:windowEventLocation];
+
+  if (![view isKindOfClass:[ChildView class]])
+    return nil;
+
+  ChildView* childView = (ChildView*)view;
+  // If childView is being destroyed return nil.
+  if (![childView widget])
+    return nil;
+  return WindowAcceptsEvent(window, aEvent, childView) ? childView : nil;
+}
+
+BOOL
+ChildViewMouseTracker::WindowAcceptsEvent(NSWindow* aWindow, NSEvent* aEvent,
+                                          ChildView* aView, BOOL aIsClickThrough)
+{
+  // Right mouse down events may get through to all windows, even to a top level
+  // window with an open sheet.
+  if (!aWindow || [aEvent type] == NSRightMouseDown)
+    return YES;
+
+  id delegate = [aWindow delegate];
+  if (!delegate || ![delegate isKindOfClass:[WindowDelegate class]])
+    return YES;
+
+  nsIWidget *windowWidget = [(WindowDelegate *)delegate geckoWidget];
+  if (!windowWidget)
+    return YES;
+
+  NSWindow* topLevelWindow = nil;
+
+  switch (windowWidget->WindowType()) {
+    case eWindowType_popup:
+      // If this is a context menu, it won't have a parent. So we'll always
+      // accept mouse move events on context menus even when none of our windows
+      // is active, which is the right thing to do.
+      // For panels, the parent window is the XUL window that owns the panel.
+      return WindowAcceptsEvent([aWindow parentWindow], aEvent, aView, aIsClickThrough);
+
+    case eWindowType_toplevel:
+    case eWindowType_dialog:
+      if ([aWindow attachedSheet])
+        return NO;
+
+      topLevelWindow = aWindow;
+      break;
+    case eWindowType_sheet: {
+      nsIWidget* parentWidget = windowWidget->GetSheetWindowParent();
+      if (!parentWidget)
+        return YES;
+
+      topLevelWindow = (NSWindow*)parentWidget->GetNativeData(NS_NATIVE_WINDOW);
+      break;
+    }
+
+    default:
+      return YES;
+  }
+
+  if (!topLevelWindow ||
+      ([topLevelWindow isMainWindow] && !aIsClickThrough) ||
+      [aEvent type] == NSOtherMouseDown ||
+      (([aEvent modifierFlags] & NSCommandKeyMask) != 0 &&
+       [aEvent type] != NSMouseMoved))
+    return YES;
+
+  // If we're here then we're dealing with a left click or mouse move on an
+  // inactive window or something similar. Ask Gecko what to do.
+  return [aView inactiveWindowAcceptsMouseEvent:aEvent];
+}
+
+#pragma mark -
+
+@interface NSView (MethodSwizzling)
+- (BOOL)nsChildView_NSView_mouseDownCanMoveWindow;
+@end
+
+@implementation NSView (MethodSwizzling)
+
+// All top-level browser windows belong to the ToolbarWindow class and have
+// NSTexturedBackgroundWindowMask turned on in their "style" (see particularly
+// [ToolbarWindow initWithContentRect:...] in nsCocoaWindow.mm).  This style
+// normally means the window "may be moved by clicking and dragging anywhere
+// in the window background", but we've suppressed this by giving the
+// ChildView class a mouseDownCanMoveWindow method that always returns NO.
+// Normally a ToolbarWindow's contentView (not a ChildView) returns YES when
+// NSTexturedBackgroundWindowMask is turned on.  But normally this makes no
+// difference.  However, under some (probably very unusual) circumstances
+// (and only on Leopard) it *does* make a difference -- for example it
+// triggers bmo bugs 431902 and 476393.  So here we make sure that a
+// ToolbarWindow's contentView always returns NO from the
+// mouseDownCanMoveWindow method.
+- (BOOL)nsChildView_NSView_mouseDownCanMoveWindow
+{
+  NSWindow *ourWindow = [self window];
+  NSView *contentView = [ourWindow contentView];
+  if ([ourWindow isKindOfClass:[ToolbarWindow class]] && (self == contentView))
+    return [ourWindow isMovableByWindowBackground];
+  return [self nsChildView_NSView_mouseDownCanMoveWindow];
+}
+
+@end
diff --git a/widget/cocoa/nsClipboard.h b/widget/cocoa/nsClipboard.h
new file mode 100644
index 0000000000..45871efe10
--- /dev/null
+++ b/widget/cocoa/nsClipboard.h
@@ -0,0 +1,55 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsClipboard_h_
+#define nsClipboard_h_
+
+#include "nsIClipboard.h"
+#include "nsXPIDLString.h"
+#include "mozilla/StaticPtr.h"
+
+#import <Cocoa/Cocoa.h>
+
+class nsITransferable;
+
+class nsClipboard : public nsIClipboard
+{
+
+public:
+  nsClipboard();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSICLIPBOARD
+
+  // On macOS, cache the transferable of the current selection (chrome/content)
+  // in the parent process. This is needed for the services menu which
+  // requires synchronous access to the current selection.
+  static mozilla::StaticRefPtr<nsITransferable> sSelectionCache;
+
+  // Helper methods, used also by nsDragService
+  static NSDictionary* PasteboardDictFromTransferable(nsITransferable *aTransferable);
+  static bool IsStringType(const nsCString& aMIMEType, NSString** aPasteboardType);
+  static NSString* WrapHtmlForSystemPasteboard(NSString* aString);
+  static nsresult TransferableFromPasteboard(nsITransferable *aTransferable, NSPasteboard *pboard);
+
+protected:
+
+  // impelement the native clipboard behavior
+  NS_IMETHOD SetNativeClipboardData(int32_t aWhichClipboard);
+  NS_IMETHOD GetNativeClipboardData(nsITransferable * aTransferable, int32_t aWhichClipboard);
+  void ClearSelectionCache();
+  void SetSelectionCache(nsITransferable* aTransferable);
+  
+private:
+  virtual ~nsClipboard();
+  int32_t mCachedClipboard;
+  int32_t mChangeCount; // Set to the native change count after any modification of the clipboard.
+
+  bool                        mIgnoreEmptyNotification;
+  nsCOMPtr<nsIClipboardOwner> mClipboardOwner;
+  nsCOMPtr<nsITransferable>   mTransferable;
+};
+
+#endif // nsClipboard_h_
diff --git a/widget/cocoa/nsClipboard.mm b/widget/cocoa/nsClipboard.mm
new file mode 100644
index 0000000000..4146f17851
--- /dev/null
+++ b/widget/cocoa/nsClipboard.mm
@@ -0,0 +1,775 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Logging.h"
+
+#include "mozilla/Unused.h"
+
+#include "gfxPlatform.h"
+#include "nsArrayUtils.h"
+#include "nsCOMPtr.h"
+#include "nsClipboard.h"
+#include "nsString.h"
+#include "nsISupportsPrimitives.h"
+#include "nsXPIDLString.h"
+#include "nsPrimitiveHelpers.h"
+#include "nsMemory.h"
+#include "nsIFile.h"
+#include "nsStringStream.h"
+#include "nsDragService.h"
+#include "nsEscape.h"
+#include "nsPrintfCString.h"
+#include "nsObjCExceptions.h"
+#include "imgIContainer.h"
+#include "nsCocoaUtils.h"
+
+using mozilla::gfx::DataSourceSurface;
+using mozilla::gfx::SourceSurface;
+using mozilla::LogLevel;
+
+// Screenshots use the (undocumented) png pasteboard type.
+#define IMAGE_PASTEBOARD_TYPES NSTIFFPboardType, @"Apple PNG pasteboard type", nil
+
+extern PRLogModuleInfo* sCocoaLog;
+
+extern void EnsureLogInitialized();
+
+mozilla::StaticRefPtr<nsITransferable> nsClipboard::sSelectionCache;
+
+nsClipboard::nsClipboard()
+  : mCachedClipboard(-1)
+  , mChangeCount(0)
+  , mIgnoreEmptyNotification(false)
+{
+  EnsureLogInitialized();
+}
+
+nsClipboard::~nsClipboard()
+{
+  EmptyClipboard(kGlobalClipboard);
+  EmptyClipboard(kFindClipboard);
+  ClearSelectionCache();
+}
+
+NS_IMPL_ISUPPORTS(nsClipboard, nsIClipboard)
+
+// We separate this into its own function because after an @try, all local
+// variables within that function get marked as volatile, and our C++ type
+// system doesn't like volatile things.
+static NSData*
+GetDataFromPasteboard(NSPasteboard* aPasteboard, NSString* aType)
+{
+  NSData *data = nil;
+  @try {
+    data = [aPasteboard dataForType:aType];
+  } @catch (NSException* e) {
+    NS_WARNING(nsPrintfCString("Exception raised while getting data from the pasteboard: \"%s - %s\"",
+                               [[e name] UTF8String], [[e reason] UTF8String]).get());
+    mozilla::Unused << e;
+  }
+  return data;
+}
+
+void
+nsClipboard::SetSelectionCache(nsITransferable *aTransferable)
+{
+  sSelectionCache = aTransferable;
+}
+
+void
+nsClipboard::ClearSelectionCache()
+{
+  sSelectionCache = nullptr;
+}
+
+NS_IMETHODIMP
+nsClipboard::SetNativeClipboardData(int32_t aWhichClipboard)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if ((aWhichClipboard != kGlobalClipboard && aWhichClipboard != kFindClipboard) || !mTransferable)
+    return NS_ERROR_FAILURE;
+
+  mIgnoreEmptyNotification = true;
+
+  NSDictionary* pasteboardOutputDict = PasteboardDictFromTransferable(mTransferable);
+  if (!pasteboardOutputDict)
+    return NS_ERROR_FAILURE;
+
+  unsigned int outputCount = [pasteboardOutputDict count];
+  NSArray* outputKeys = [pasteboardOutputDict allKeys];
+  NSPasteboard* cocoaPasteboard;
+  if (aWhichClipboard == kFindClipboard) {
+    cocoaPasteboard = [NSPasteboard pasteboardWithName:NSFindPboard];
+    [cocoaPasteboard declareTypes:[NSArray arrayWithObject:NSStringPboardType] owner:nil];
+  } else {
+    // Write everything else out to the general pasteboard.
+    cocoaPasteboard = [NSPasteboard generalPasteboard];
+    [cocoaPasteboard declareTypes:outputKeys owner:nil];
+  }
+
+  for (unsigned int i = 0; i < outputCount; i++) {
+    NSString* currentKey = [outputKeys objectAtIndex:i];
+    id currentValue = [pasteboardOutputDict valueForKey:currentKey];
+    if (aWhichClipboard == kFindClipboard) {
+      if (currentKey == NSStringPboardType)
+        [cocoaPasteboard setString:currentValue forType:currentKey];
+    } else {
+      if (currentKey == NSStringPboardType ||
+          currentKey == kCorePboardType_url ||
+          currentKey == kCorePboardType_urld ||
+          currentKey == kCorePboardType_urln) {
+        [cocoaPasteboard setString:currentValue forType:currentKey];
+      } else if (currentKey == NSHTMLPboardType) {
+        [cocoaPasteboard setString:(nsClipboard::WrapHtmlForSystemPasteboard(currentValue))
+                         forType:currentKey];
+      } else {
+        [cocoaPasteboard setData:currentValue forType:currentKey];
+      }
+    }
+  }
+
+  mCachedClipboard = aWhichClipboard;
+  mChangeCount = [cocoaPasteboard changeCount];
+
+  mIgnoreEmptyNotification = false;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult
+nsClipboard::TransferableFromPasteboard(nsITransferable *aTransferable, NSPasteboard *cocoaPasteboard)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // get flavor list that includes all acceptable flavors (including ones obtained through conversion)
+  nsCOMPtr<nsIArray> flavorList;
+  nsresult rv = aTransferable->FlavorsTransferableCanImport(getter_AddRefs(flavorList));
+  if (NS_FAILED(rv))
+    return NS_ERROR_FAILURE;
+
+  uint32_t flavorCount;
+  flavorList->GetLength(&flavorCount);
+
+  for (uint32_t i = 0; i < flavorCount; i++) {
+    nsCOMPtr<nsISupportsCString> currentFlavor = do_QueryElementAt(flavorList, i);
+    if (!currentFlavor)
+      continue;
+
+    nsXPIDLCString flavorStr;
+    currentFlavor->ToString(getter_Copies(flavorStr)); // i has a flavr
+
+    // printf("looking for clipboard data of type %s\n", flavorStr.get());
+
+    NSString *pboardType = nil;
+    if (nsClipboard::IsStringType(flavorStr, &pboardType)) {
+      NSString* pString = [cocoaPasteboard stringForType:pboardType];
+      if (!pString)
+        continue;
+
+      NSData* stringData;
+      if ([pboardType isEqualToString:NSRTFPboardType]) {
+        stringData = [pString dataUsingEncoding:NSASCIIStringEncoding];
+      } else {
+        stringData = [pString dataUsingEncoding:NSUnicodeStringEncoding];
+      }
+      unsigned int dataLength = [stringData length];
+      void* clipboardDataPtr = malloc(dataLength);
+      if (!clipboardDataPtr)
+        return NS_ERROR_OUT_OF_MEMORY;
+      [stringData getBytes:clipboardDataPtr];
+
+      // The DOM only wants LF, so convert from MacOS line endings to DOM line endings.
+      int32_t signedDataLength = dataLength;
+      nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(flavorStr, &clipboardDataPtr, &signedDataLength);
+      dataLength = signedDataLength;
+
+      // skip BOM (Byte Order Mark to distinguish little or big endian)      
+      char16_t* clipboardDataPtrNoBOM = (char16_t*)clipboardDataPtr;
+      if ((dataLength > 2) &&
+          ((clipboardDataPtrNoBOM[0] == 0xFEFF) ||
+           (clipboardDataPtrNoBOM[0] == 0xFFFE))) {
+        dataLength -= sizeof(char16_t);
+        clipboardDataPtrNoBOM += 1;
+      }
+
+      nsCOMPtr<nsISupports> genericDataWrapper;
+      nsPrimitiveHelpers::CreatePrimitiveForData(flavorStr, clipboardDataPtrNoBOM, dataLength,
+                                                 getter_AddRefs(genericDataWrapper));
+      aTransferable->SetTransferData(flavorStr, genericDataWrapper, dataLength);
+      free(clipboardDataPtr);
+      break;
+    }
+    else if (flavorStr.EqualsLiteral(kCustomTypesMime)) {
+      NSString* type = [cocoaPasteboard availableTypeFromArray:[NSArray arrayWithObject:kCustomTypesPboardType]];
+      if (!type) {
+        continue;
+      }
+
+      NSData* pasteboardData = GetDataFromPasteboard(cocoaPasteboard, type);
+      if (!pasteboardData) {
+        continue;
+      }
+
+      unsigned int dataLength = [pasteboardData length];
+      void* clipboardDataPtr = malloc(dataLength);
+      if (!clipboardDataPtr) {
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+      [pasteboardData getBytes:clipboardDataPtr];
+
+      nsCOMPtr<nsISupports> genericDataWrapper;
+      nsPrimitiveHelpers::CreatePrimitiveForData(flavorStr, clipboardDataPtr, dataLength,
+                                                 getter_AddRefs(genericDataWrapper));
+
+      aTransferable->SetTransferData(flavorStr, genericDataWrapper, dataLength);
+      free(clipboardDataPtr);
+    }
+    else if (flavorStr.EqualsLiteral(kJPEGImageMime) ||
+             flavorStr.EqualsLiteral(kJPGImageMime) ||
+             flavorStr.EqualsLiteral(kPNGImageMime) ||
+             flavorStr.EqualsLiteral(kGIFImageMime)) {
+      // Figure out if there's data on the pasteboard we can grab (sanity check)
+      NSString *type = [cocoaPasteboard availableTypeFromArray:[NSArray arrayWithObjects:IMAGE_PASTEBOARD_TYPES]];
+      if (!type)
+        continue;
+
+      // Read data off the clipboard
+      NSData *pasteboardData = GetDataFromPasteboard(cocoaPasteboard, type);
+      if (!pasteboardData)
+        continue;
+
+      // Figure out what type we're converting to
+      CFStringRef outputType = NULL; 
+      if (flavorStr.EqualsLiteral(kJPEGImageMime) ||
+          flavorStr.EqualsLiteral(kJPGImageMime))
+        outputType = CFSTR("public.jpeg");
+      else if (flavorStr.EqualsLiteral(kPNGImageMime))
+        outputType = CFSTR("public.png");
+      else if (flavorStr.EqualsLiteral(kGIFImageMime))
+        outputType = CFSTR("com.compuserve.gif");
+      else
+        continue;
+
+      // Use ImageIO to interpret the data on the clipboard and transcode.
+      // Note that ImageIO, like all CF APIs, allows NULLs to propagate freely
+      // and safely in most cases (like ObjC). A notable exception is CFRelease.
+      NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
+                                (NSNumber*)kCFBooleanTrue, kCGImageSourceShouldAllowFloat,
+                                (type == NSTIFFPboardType ? @"public.tiff" : @"public.png"),
+                                kCGImageSourceTypeIdentifierHint, nil];
+
+      CGImageSourceRef source = CGImageSourceCreateWithData((CFDataRef)pasteboardData, 
+                                                            (CFDictionaryRef)options);
+      NSMutableData *encodedData = [NSMutableData data];
+      CGImageDestinationRef dest = CGImageDestinationCreateWithData((CFMutableDataRef)encodedData,
+                                                                    outputType,
+                                                                    1, NULL);
+      CGImageDestinationAddImageFromSource(dest, source, 0, NULL);
+      bool successfullyConverted = CGImageDestinationFinalize(dest);
+
+      if (successfullyConverted) {
+        // Put the converted data in a form Gecko can understand
+        nsCOMPtr<nsIInputStream> byteStream;
+        NS_NewByteInputStream(getter_AddRefs(byteStream), (const char*)[encodedData bytes],
+                                   [encodedData length], NS_ASSIGNMENT_COPY);
+  
+        aTransferable->SetTransferData(flavorStr, byteStream, sizeof(nsIInputStream*));
+      }
+
+      if (dest)
+        CFRelease(dest);
+      if (source)
+        CFRelease(source);
+      
+      if (successfullyConverted)
+        break;
+      else
+        continue;
+    }
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsClipboard::GetNativeClipboardData(nsITransferable* aTransferable, int32_t aWhichClipboard)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if ((aWhichClipboard != kGlobalClipboard && aWhichClipboard != kFindClipboard) || !aTransferable)
+    return NS_ERROR_FAILURE;
+
+  NSPasteboard* cocoaPasteboard;
+  if (aWhichClipboard == kFindClipboard) {
+    cocoaPasteboard = [NSPasteboard pasteboardWithName:NSFindPboard];
+  } else {
+    cocoaPasteboard = [NSPasteboard generalPasteboard];
+  }
+  if (!cocoaPasteboard)
+    return NS_ERROR_FAILURE;
+
+  // get flavor list that includes all acceptable flavors (including ones obtained through conversion)
+  nsCOMPtr<nsIArray> flavorList;
+  nsresult rv = aTransferable->FlavorsTransferableCanImport(getter_AddRefs(flavorList));
+  if (NS_FAILED(rv))
+    return NS_ERROR_FAILURE;
+
+  uint32_t flavorCount;
+  flavorList->GetLength(&flavorCount);
+
+  // If we were the last ones to put something on the pasteboard, then just use the cached
+  // transferable. Otherwise clear it because it isn't relevant any more.
+  if (mCachedClipboard == aWhichClipboard &&
+      mChangeCount == [cocoaPasteboard changeCount]) {
+    if (mTransferable) {
+      for (uint32_t i = 0; i < flavorCount; i++) {
+        nsCOMPtr<nsISupportsCString> currentFlavor = do_QueryElementAt(flavorList, i);
+        if (!currentFlavor)
+          continue;
+
+        nsXPIDLCString flavorStr;
+        currentFlavor->ToString(getter_Copies(flavorStr));
+
+        nsCOMPtr<nsISupports> dataSupports;
+        uint32_t dataSize = 0;
+        rv = mTransferable->GetTransferData(flavorStr, getter_AddRefs(dataSupports), &dataSize);
+        if (NS_SUCCEEDED(rv)) {
+          aTransferable->SetTransferData(flavorStr, dataSupports, dataSize);
+          return NS_OK; // maybe try to fill in more types? Is there a point?
+        }
+      }
+    }
+  } else {
+    EmptyClipboard(aWhichClipboard);
+  }
+
+  // at this point we can't satisfy the request from cache data so let's look
+  // for things other people put on the system clipboard
+
+  return nsClipboard::TransferableFromPasteboard(aTransferable, cocoaPasteboard);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// returns true if we have *any* of the passed in flavors available for pasting
+NS_IMETHODIMP
+nsClipboard::HasDataMatchingFlavors(const char** aFlavorList, uint32_t aLength,
+                                    int32_t aWhichClipboard, bool* outResult)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  *outResult = false;
+
+  if ((aWhichClipboard != kGlobalClipboard) || !aFlavorList)
+    return NS_OK;
+
+  // first see if we have data for this in our cached transferable
+  if (mTransferable) {
+    nsCOMPtr<nsIArray> transferableFlavorList;
+    nsresult rv = mTransferable->FlavorsTransferableCanImport(getter_AddRefs(transferableFlavorList));
+    if (NS_SUCCEEDED(rv)) {
+      uint32_t transferableFlavorCount;
+      transferableFlavorList->GetLength(&transferableFlavorCount);
+      for (uint32_t j = 0; j < transferableFlavorCount; j++) {
+        nsCOMPtr<nsISupportsCString> currentTransferableFlavor =
+            do_QueryElementAt(transferableFlavorList, j);
+        if (!currentTransferableFlavor)
+          continue;
+        nsXPIDLCString transferableFlavorStr;
+        currentTransferableFlavor->ToString(getter_Copies(transferableFlavorStr));
+
+        for (uint32_t k = 0; k < aLength; k++) {
+          if (transferableFlavorStr.Equals(aFlavorList[k])) {
+            *outResult = true;
+            return NS_OK;
+          }
+        }
+      }      
+    }    
+  }
+
+  NSPasteboard* generalPBoard = [NSPasteboard generalPasteboard];
+
+  for (uint32_t i = 0; i < aLength; i++) {
+    nsDependentCString mimeType(aFlavorList[i]);
+    NSString *pboardType = nil;
+
+    if (nsClipboard::IsStringType(mimeType, &pboardType)) {
+      NSString* availableType = [generalPBoard availableTypeFromArray:[NSArray arrayWithObject:pboardType]];
+      if (availableType && [availableType isEqualToString:pboardType]) {
+        *outResult = true;
+        break;
+      }
+    } else if (!strcmp(aFlavorList[i], kCustomTypesMime)) {
+      NSString* availableType = [generalPBoard availableTypeFromArray:[NSArray arrayWithObject:kCustomTypesPboardType]];
+      if (availableType) {
+        *outResult = true;
+        break;
+      }
+    } else if (!strcmp(aFlavorList[i], kJPEGImageMime) ||
+               !strcmp(aFlavorList[i], kJPGImageMime) ||
+               !strcmp(aFlavorList[i], kPNGImageMime) ||
+               !strcmp(aFlavorList[i], kGIFImageMime)) {
+      NSString* availableType = [generalPBoard availableTypeFromArray:
+                                  [NSArray arrayWithObjects:IMAGE_PASTEBOARD_TYPES]];
+      if (availableType) {
+        *outResult = true;
+        break;
+      }
+    }
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsClipboard::SupportsFindClipboard(bool *_retval)
+{
+  NS_ENSURE_ARG_POINTER(_retval);
+  *_retval = true;
+  return NS_OK;
+}
+
+// This function converts anything that other applications might understand into the system format
+// and puts it into a dictionary which it returns.
+// static
+NSDictionary* 
+nsClipboard::PasteboardDictFromTransferable(nsITransferable* aTransferable)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if (!aTransferable)
+    return nil;
+
+  NSMutableDictionary* pasteboardOutputDict = [NSMutableDictionary dictionary];
+
+  nsCOMPtr<nsIArray> flavorList;
+  nsresult rv = aTransferable->FlavorsTransferableCanExport(getter_AddRefs(flavorList));
+  if (NS_FAILED(rv))
+    return nil;
+
+  uint32_t flavorCount;
+  flavorList->GetLength(&flavorCount);
+  for (uint32_t i = 0; i < flavorCount; i++) {
+    nsCOMPtr<nsISupportsCString> currentFlavor = do_QueryElementAt(flavorList, i);
+    if (!currentFlavor)
+      continue;
+
+    nsXPIDLCString flavorStr;
+    currentFlavor->ToString(getter_Copies(flavorStr));
+
+    MOZ_LOG(sCocoaLog, LogLevel::Info, ("writing out clipboard data of type %s (%d)\n", flavorStr.get(), i));
+
+    NSString *pboardType = nil;
+
+    if (nsClipboard::IsStringType(flavorStr, &pboardType)) {
+      void* data = nullptr;
+      uint32_t dataSize = 0;
+      nsCOMPtr<nsISupports> genericDataWrapper;
+      rv = aTransferable->GetTransferData(flavorStr, getter_AddRefs(genericDataWrapper), &dataSize);
+      nsPrimitiveHelpers::CreateDataFromPrimitive(flavorStr, genericDataWrapper, &data, dataSize);
+
+      NSString* nativeString;
+      if (data)
+        nativeString = [NSString stringWithCharacters:(const unichar*)data length:(dataSize / sizeof(char16_t))];
+      else
+        nativeString = [NSString string];
+      
+      // be nice to Carbon apps, normalize the receiver's contents using Form C.
+      nativeString = [nativeString precomposedStringWithCanonicalMapping];
+
+      [pasteboardOutputDict setObject:nativeString forKey:pboardType];
+      
+      free(data);
+    }
+    else if (flavorStr.EqualsLiteral(kCustomTypesMime)) {
+      void* data = nullptr;
+      uint32_t dataSize = 0;
+      nsCOMPtr<nsISupports> genericDataWrapper;
+      rv = aTransferable->GetTransferData(flavorStr, getter_AddRefs(genericDataWrapper), &dataSize);
+      nsPrimitiveHelpers::CreateDataFromPrimitive(flavorStr, genericDataWrapper, &data, dataSize);
+
+      if (data) {
+        NSData* nativeData = [NSData dataWithBytes:data length:dataSize];
+
+        [pasteboardOutputDict setObject:nativeData forKey:kCustomTypesPboardType];
+        free(data);
+      }
+    }
+    else if (flavorStr.EqualsLiteral(kPNGImageMime) || flavorStr.EqualsLiteral(kJPEGImageMime) ||
+             flavorStr.EqualsLiteral(kJPGImageMime) || flavorStr.EqualsLiteral(kGIFImageMime) ||
+             flavorStr.EqualsLiteral(kNativeImageMime)) {
+      uint32_t dataSize = 0;
+      nsCOMPtr<nsISupports> transferSupports;
+      aTransferable->GetTransferData(flavorStr, getter_AddRefs(transferSupports), &dataSize);
+      nsCOMPtr<nsISupportsInterfacePointer> ptrPrimitive(do_QueryInterface(transferSupports));
+      if (!ptrPrimitive)
+        continue;
+
+      nsCOMPtr<nsISupports> primitiveData;
+      ptrPrimitive->GetData(getter_AddRefs(primitiveData));
+
+      nsCOMPtr<imgIContainer> image(do_QueryInterface(primitiveData));
+      if (!image) {
+        NS_WARNING("Image isn't an imgIContainer in transferable");
+        continue;
+      }
+
+      RefPtr<SourceSurface> surface =
+        image->GetFrame(imgIContainer::FRAME_CURRENT,
+                        imgIContainer::FLAG_SYNC_DECODE);
+      if (!surface) {
+        continue;
+      }
+      CGImageRef imageRef = NULL;
+      rv = nsCocoaUtils::CreateCGImageFromSurface(surface, &imageRef);
+      if (NS_FAILED(rv) || !imageRef) {
+        continue;
+      }
+
+      // Convert the CGImageRef to TIFF data.
+      CFMutableDataRef tiffData = CFDataCreateMutable(kCFAllocatorDefault, 0);
+      CGImageDestinationRef destRef = CGImageDestinationCreateWithData(tiffData,
+                                                                       CFSTR("public.tiff"),
+                                                                       1,
+                                                                       NULL);
+      CGImageDestinationAddImage(destRef, imageRef, NULL);
+      bool successfullyConverted = CGImageDestinationFinalize(destRef);
+
+      CGImageRelease(imageRef);
+      if (destRef)
+        CFRelease(destRef);
+
+      if (!successfullyConverted) {
+        if (tiffData)
+          CFRelease(tiffData);
+        continue;
+      }
+
+      [pasteboardOutputDict setObject:(NSMutableData*)tiffData forKey:NSTIFFPboardType];
+      if (tiffData)
+        CFRelease(tiffData);
+    }
+    else if (flavorStr.EqualsLiteral(kFileMime)) {
+      uint32_t len = 0;
+      nsCOMPtr<nsISupports> genericFile;
+      rv = aTransferable->GetTransferData(flavorStr, getter_AddRefs(genericFile), &len);
+      if (NS_FAILED(rv)) {
+        continue;
+      }
+
+      nsCOMPtr<nsIFile> file(do_QueryInterface(genericFile));
+      if (!file) {
+        nsCOMPtr<nsISupportsInterfacePointer> ptr(do_QueryInterface(genericFile));
+
+        if (ptr) {
+          ptr->GetData(getter_AddRefs(genericFile));
+          file = do_QueryInterface(genericFile);
+        }
+      }
+
+      if (!file) {
+        continue;
+      }
+
+      nsAutoString fileURI;
+      rv = file->GetPath(fileURI);
+      if (NS_FAILED(rv)) {
+        continue;
+      }
+
+      NSString* str = nsCocoaUtils::ToNSString(fileURI);
+      NSArray* fileList = [NSArray arrayWithObjects:str, nil];
+      [pasteboardOutputDict setObject:fileList forKey:NSFilenamesPboardType];
+    }
+    else if (flavorStr.EqualsLiteral(kFilePromiseMime)) {
+      [pasteboardOutputDict setObject:[NSArray arrayWithObject:@""] forKey:NSFilesPromisePboardType];      
+    }
+    else if (flavorStr.EqualsLiteral(kURLMime)) {
+      uint32_t len = 0;
+      nsCOMPtr<nsISupports> genericURL;
+      rv = aTransferable->GetTransferData(flavorStr, getter_AddRefs(genericURL), &len);
+      nsCOMPtr<nsISupportsString> urlObject(do_QueryInterface(genericURL));
+
+      nsAutoString url;
+      urlObject->GetData(url);
+
+      // A newline embedded in the URL means that the form is actually URL + title.
+      int32_t newlinePos = url.FindChar(char16_t('\n'));
+      if (newlinePos >= 0) {
+        url.Truncate(newlinePos);
+
+        nsAutoString urlTitle;
+        urlObject->GetData(urlTitle);
+        urlTitle.Mid(urlTitle, newlinePos + 1, len - (newlinePos + 1));
+
+        NSString *nativeTitle = [[NSString alloc] initWithCharacters:reinterpret_cast<const unichar*>(urlTitle.get())
+                                                              length:urlTitle.Length()];
+        // be nice to Carbon apps, normalize the receiver's contents using Form C.
+        [pasteboardOutputDict setObject:[nativeTitle precomposedStringWithCanonicalMapping] forKey:kCorePboardType_urln];
+        // Also put the title out as 'urld', since some recipients will look for that.
+        [pasteboardOutputDict setObject:[nativeTitle precomposedStringWithCanonicalMapping] forKey:kCorePboardType_urld];
+        [nativeTitle release];
+      }
+
+      // The Finder doesn't like getting random binary data aka
+      // Unicode, so change it into an escaped URL containing only
+      // ASCII.
+      nsAutoCString utf8Data = NS_ConvertUTF16toUTF8(url.get(), url.Length());
+      nsAutoCString escData;
+      NS_EscapeURL(utf8Data.get(), utf8Data.Length(), esc_OnlyNonASCII|esc_AlwaysCopy, escData);
+
+      // printf("Escaped url is %s, length %d\n", escData.get(), escData.Length());
+
+      NSString *nativeURL = [NSString stringWithUTF8String:escData.get()];
+      [pasteboardOutputDict setObject:nativeURL forKey:kCorePboardType_url];
+    }
+    // If it wasn't a type that we recognize as exportable we don't put it on the system
+    // clipboard. We'll just access it from our cached transferable when we need it.
+  }
+
+  return pasteboardOutputDict;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+bool nsClipboard::IsStringType(const nsCString& aMIMEType, NSString** aPasteboardType)
+{
+  if (aMIMEType.EqualsLiteral(kUnicodeMime)) {
+    *aPasteboardType = NSStringPboardType;
+    return true;
+  } else if (aMIMEType.EqualsLiteral(kRTFMime)) {
+    *aPasteboardType = NSRTFPboardType;
+    return true;
+  } else if (aMIMEType.EqualsLiteral(kHTMLMime)) {
+    *aPasteboardType = NSHTMLPboardType;
+    return true;
+  } else {
+    return false;
+  }
+}
+
+NSString* nsClipboard::WrapHtmlForSystemPasteboard(NSString* aString)
+{
+  NSString* wrapped =
+    [NSString stringWithFormat:
+      @"<html>"
+         "<head>"
+           "<meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\">"
+         "</head>"
+         "<body>"
+           "%@"
+         "</body>"
+       "</html>", aString];
+  return wrapped;
+}
+
+/**
+  * Sets the transferable object
+  *
+  */
+NS_IMETHODIMP
+nsClipboard::SetData(nsITransferable* aTransferable, nsIClipboardOwner* anOwner,
+                     int32_t aWhichClipboard)
+{
+  NS_ASSERTION (aTransferable, "clipboard given a null transferable");
+
+  if (aWhichClipboard == kSelectionCache) {
+    if (aTransferable) {
+      SetSelectionCache(aTransferable);
+      return NS_OK;
+    }
+    return NS_ERROR_FAILURE;
+  }
+
+  if (aTransferable == mTransferable && anOwner == mClipboardOwner) {
+    return NS_OK;
+  }
+  bool selectClipPresent;
+  SupportsSelectionClipboard(&selectClipPresent);
+  bool findClipPresent;
+  SupportsFindClipboard(&findClipPresent);
+  if (!selectClipPresent && !findClipPresent && aWhichClipboard != kGlobalClipboard) {
+    return NS_ERROR_FAILURE;
+  }
+
+  EmptyClipboard(aWhichClipboard);
+
+  mClipboardOwner = anOwner;
+  mTransferable = aTransferable;
+
+  nsresult rv = NS_ERROR_FAILURE;
+  if (mTransferable) {
+    rv = SetNativeClipboardData(aWhichClipboard);
+  }
+
+  return rv;
+}
+
+/**
+  * Gets the transferable object
+  *
+  */
+NS_IMETHODIMP
+nsClipboard::GetData(nsITransferable* aTransferable, int32_t aWhichClipboard)
+{
+  NS_ASSERTION (aTransferable, "clipboard given a null transferable");
+
+  bool selectClipPresent;
+  SupportsSelectionClipboard(&selectClipPresent);
+  bool findClipPresent;
+  SupportsFindClipboard(&findClipPresent);
+  if (!selectClipPresent && !findClipPresent && aWhichClipboard != kGlobalClipboard)
+    return NS_ERROR_FAILURE;
+
+  if (aTransferable) {
+    return GetNativeClipboardData(aTransferable, aWhichClipboard);
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsClipboard::EmptyClipboard(int32_t aWhichClipboard)
+{
+  if (aWhichClipboard == kSelectionCache) {
+    ClearSelectionCache();
+    return NS_OK;
+  }
+
+  bool selectClipPresent;
+  SupportsSelectionClipboard(&selectClipPresent);
+  bool findClipPresent;
+  SupportsFindClipboard(&findClipPresent);
+  if (!selectClipPresent && !findClipPresent && aWhichClipboard != kGlobalClipboard) {
+    return NS_ERROR_FAILURE;
+  }
+
+  if (mIgnoreEmptyNotification) {
+    return NS_OK;
+  }
+
+  if (mClipboardOwner) {
+    mClipboardOwner->LosingOwnership(mTransferable);
+    mClipboardOwner = nullptr;
+  }
+
+  mTransferable = nullptr;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsClipboard::SupportsSelectionClipboard(bool* _retval)
+{
+  *_retval = false;   // we don't support the selection clipboard by default.
+  return NS_OK;
+}
diff --git a/widget/cocoa/nsCocoaDebugUtils.h b/widget/cocoa/nsCocoaDebugUtils.h
new file mode 100644
index 0000000000..814f060878
--- /dev/null
+++ b/widget/cocoa/nsCocoaDebugUtils.h
@@ -0,0 +1,136 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsCocoaDebugUtils_h_
+#define nsCocoaDebugUtils_h_
+
+#include <CoreServices/CoreServices.h>
+
+// Definitions and declarations of stuff used by us from the CoreSymbolication
+// framework.  This is an undocumented, private framework available on OS X
+// 10.6 and up.  It's used by Apple utilities like dtrace, atos, ReportCrash
+// and crashreporterd.
+
+typedef struct _CSTypeRef {
+  unsigned long type;
+  void* contents;
+} CSTypeRef;
+
+typedef CSTypeRef CSSymbolicatorRef;
+typedef CSTypeRef CSSymbolOwnerRef;
+typedef CSTypeRef CSSymbolRef;
+typedef CSTypeRef CSSourceInfoRef;
+
+typedef struct _CSRange {
+  unsigned long long location;
+  unsigned long long length;
+} CSRange;
+
+typedef unsigned long long CSArchitecture;
+
+#define kCSNow LONG_MAX
+
+extern "C" {
+
+CSSymbolicatorRef
+CSSymbolicatorCreateWithPid(pid_t pid);
+
+CSSymbolicatorRef
+CSSymbolicatorCreateWithPidFlagsAndNotification(pid_t pid,
+                                                uint32_t flags,
+                                                uint32_t notification);
+
+CSArchitecture
+CSSymbolicatorGetArchitecture(CSSymbolicatorRef symbolicator);
+
+CSSymbolOwnerRef
+CSSymbolicatorGetSymbolOwnerWithAddressAtTime(CSSymbolicatorRef symbolicator,
+                                              unsigned long long address,
+                                              long time);
+
+const char*
+CSSymbolOwnerGetName(CSSymbolOwnerRef owner);
+
+unsigned long long
+CSSymbolOwnerGetBaseAddress(CSSymbolOwnerRef owner);
+
+CSSymbolRef
+CSSymbolOwnerGetSymbolWithAddress(CSSymbolOwnerRef owner,
+                                  unsigned long long address);
+
+CSSourceInfoRef
+CSSymbolOwnerGetSourceInfoWithAddress(CSSymbolOwnerRef owner,
+                                      unsigned long long address);
+
+const char*
+CSSymbolGetName(CSSymbolRef symbol);
+
+CSRange
+CSSymbolGetRange(CSSymbolRef symbol);
+
+const char*
+CSSourceInfoGetFilename(CSSourceInfoRef info);
+
+uint32_t
+CSSourceInfoGetLineNumber(CSSourceInfoRef info);
+
+CSTypeRef
+CSRetain(CSTypeRef);
+
+void
+CSRelease(CSTypeRef);
+
+bool
+CSIsNull(CSTypeRef);
+
+void
+CSShow(CSTypeRef);
+
+const char*
+CSArchitectureGetFamilyName(CSArchitecture);
+
+} // extern "C"
+
+class nsCocoaDebugUtils
+{
+public:
+  // Like NSLog() but records more information (for example the full path to
+  // the executable and the "thread name").  Like NSLog(), writes to both
+  // stdout and the system log.
+  static void DebugLog(const char* aFormat, ...);
+
+  // Logs a stack trace of the current point of execution, to both stdout and
+  // the system log.
+  static void PrintStackTrace();
+
+  // Returns the name of the module that "owns" aAddress.  This must be
+  // free()ed by the caller.
+  static char* GetOwnerName(void* aAddress);
+
+  // Returns a symbolicated representation of aAddress.  This must be
+  // free()ed by the caller.
+  static char* GetAddressString(void* aAddress);
+
+private:
+  static void DebugLogInt(bool aDecorate, const char* aFormat, ...);
+  static void DebugLogV(bool aDecorate, CFStringRef aFormat, va_list aArgs);
+
+  static void PrintAddress(void* aAddress);
+
+  // The values returned by GetOwnerNameInt() and GetAddressStringInt() must
+  // be free()ed by the caller.
+  static char* GetOwnerNameInt(void* aAddress,
+                               CSTypeRef aOwner = sInitializer);
+  static char* GetAddressStringInt(void* aAddress,
+                                   CSTypeRef aOwner = sInitializer);
+
+  static CSSymbolicatorRef GetSymbolicatorRef();
+  static void ReleaseSymbolicator();
+
+  static CSTypeRef sInitializer;
+  static CSSymbolicatorRef sSymbolicator;
+};
+
+#endif // nsCocoaDebugUtils_h_
diff --git a/widget/cocoa/nsCocoaDebugUtils.mm b/widget/cocoa/nsCocoaDebugUtils.mm
new file mode 100644
index 0000000000..35896dc401
--- /dev/null
+++ b/widget/cocoa/nsCocoaDebugUtils.mm
@@ -0,0 +1,284 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsCocoaDebugUtils.h"
+
+#include <pthread.h>
+#include <libproc.h>
+#include <stdarg.h>
+#include <time.h>
+#include <execinfo.h>
+#include <asl.h>
+
+static char gProcPath[PROC_PIDPATHINFO_MAXSIZE] = {0};
+static char gBundleID[MAXPATHLEN] = {0};
+
+static void MaybeGetPathAndID()
+{
+  if (!gProcPath[0]) {
+    proc_pidpath(getpid(), gProcPath, sizeof(gProcPath));
+  }
+  if (!gBundleID[0]) {
+    // Apple's CFLog() uses "com.apple.console" (in its call to asl_open()) if
+    // it can't find the bundle id.
+    CFStringRef bundleID = NULL;
+    CFBundleRef mainBundle = CFBundleGetMainBundle();
+    if (mainBundle) {
+      bundleID = CFBundleGetIdentifier(mainBundle);
+    }
+    if (!bundleID) {
+      strcpy(gBundleID, "com.apple.console");
+    } else {
+      CFStringGetCString(bundleID, gBundleID, sizeof(gBundleID),
+                         kCFStringEncodingUTF8);
+    }
+  }
+}
+
+static void GetThreadName(char* aName, size_t aSize)
+{
+  pthread_getname_np(pthread_self(), aName, aSize);
+}
+
+void
+nsCocoaDebugUtils::DebugLog(const char* aFormat, ...)
+{
+  va_list args;
+  va_start(args, aFormat);
+  CFStringRef formatCFSTR =
+    CFStringCreateWithCString(kCFAllocatorDefault, aFormat,
+                              kCFStringEncodingUTF8);
+  DebugLogV(true, formatCFSTR, args);
+  CFRelease(formatCFSTR);
+  va_end(args);
+}
+
+void
+nsCocoaDebugUtils::DebugLogInt(bool aDecorate, const char* aFormat, ...)
+{
+  va_list args;
+  va_start(args, aFormat);
+  CFStringRef formatCFSTR =
+    CFStringCreateWithCString(kCFAllocatorDefault, aFormat,
+                              kCFStringEncodingUTF8);
+  DebugLogV(aDecorate, formatCFSTR, args);
+  CFRelease(formatCFSTR);
+  va_end(args);
+}
+
+void
+nsCocoaDebugUtils::DebugLogV(bool aDecorate, CFStringRef aFormat,
+                             va_list aArgs)
+{
+  MaybeGetPathAndID();
+
+  CFStringRef message =
+    CFStringCreateWithFormatAndArguments(kCFAllocatorDefault, NULL,
+                                         aFormat, aArgs);
+
+  int msgLength =
+    CFStringGetMaximumSizeForEncoding(CFStringGetLength(message),
+                                      kCFStringEncodingUTF8);
+  char* msgUTF8 = (char*) calloc(msgLength, 1);
+  CFStringGetCString(message, msgUTF8, msgLength, kCFStringEncodingUTF8);
+  CFRelease(message);
+
+  int finishedLength = msgLength + PROC_PIDPATHINFO_MAXSIZE;
+  char* finished = (char*) calloc(finishedLength, 1);
+  const time_t currentTime = time(NULL);
+  char timestamp[30] = {0};
+  ctime_r(&currentTime, timestamp);
+  if (aDecorate) {
+    char threadName[MAXPATHLEN] = {0};
+    GetThreadName(threadName, sizeof(threadName));
+    snprintf(finished, finishedLength, "(%s) %s[%u] %s[%p] %s\n",
+            timestamp, gProcPath, getpid(), threadName, pthread_self(), msgUTF8);
+  } else {
+    snprintf(finished, finishedLength, "%s\n", msgUTF8);
+  }
+  free(msgUTF8);
+
+  fputs(finished, stdout);
+
+  // Use the Apple System Log facility, as NSLog and CFLog do.
+  aslclient asl = asl_open(NULL, gBundleID, ASL_OPT_NO_DELAY);
+  aslmsg msg = asl_new(ASL_TYPE_MSG);
+  asl_set(msg, ASL_KEY_LEVEL, "4"); // kCFLogLevelWarning, used by NSLog()
+  asl_set(msg, ASL_KEY_MSG, finished);
+  asl_send(asl, msg);
+  asl_free(msg);
+  asl_close(asl);
+
+  free(finished);
+}
+
+CSTypeRef
+nsCocoaDebugUtils::sInitializer = {0};
+
+CSSymbolicatorRef
+nsCocoaDebugUtils::sSymbolicator = {0};
+
+#define STACK_MAX 256
+
+void
+nsCocoaDebugUtils::PrintStackTrace()
+{
+  void** addresses = (void**) calloc(STACK_MAX, sizeof(void*));
+  if (!addresses) {
+    return;
+  }
+
+  CSSymbolicatorRef symbolicator = GetSymbolicatorRef();
+  if (CSIsNull(symbolicator)) {
+    free(addresses);
+    return;
+  }
+
+  uint32_t count = backtrace(addresses, STACK_MAX);
+  for (uint32_t i = 0; i < count; ++i) {
+    PrintAddress(addresses[i]);
+  }
+
+  ReleaseSymbolicator();
+  free(addresses);
+}
+
+void
+nsCocoaDebugUtils::PrintAddress(void* aAddress)
+{
+  const char* ownerName = "unknown";
+  const char* addressString = "unknown + 0";
+
+  char* allocatedOwnerName = nullptr;
+  char* allocatedAddressString = nullptr;
+
+  CSSymbolOwnerRef owner = {0};
+  CSSymbolicatorRef symbolicator = GetSymbolicatorRef();
+
+  if (!CSIsNull(symbolicator)) {
+    owner =
+      CSSymbolicatorGetSymbolOwnerWithAddressAtTime(symbolicator,
+                                                    (unsigned long long) aAddress,
+                                                    kCSNow);
+  }
+  if (!CSIsNull(owner)) {
+    ownerName = allocatedOwnerName = GetOwnerNameInt(aAddress, owner);
+    addressString = allocatedAddressString = GetAddressStringInt(aAddress, owner);
+  }
+  DebugLogInt(false, "    (%s) %s", ownerName, addressString);
+
+  free(allocatedOwnerName);
+  free(allocatedAddressString);
+
+  ReleaseSymbolicator();
+}
+
+char*
+nsCocoaDebugUtils::GetOwnerName(void* aAddress)
+{
+  return GetOwnerNameInt(aAddress);
+}
+
+char*
+nsCocoaDebugUtils::GetOwnerNameInt(void* aAddress, CSTypeRef aOwner)
+{
+  char* retval = (char*) calloc(MAXPATHLEN, 1);
+
+  const char* ownerName = "unknown";
+
+  CSSymbolicatorRef symbolicator = GetSymbolicatorRef();
+  CSTypeRef owner = aOwner;
+
+  if (CSIsNull(owner) && !CSIsNull(symbolicator)) {
+    owner =
+      CSSymbolicatorGetSymbolOwnerWithAddressAtTime(symbolicator,
+                                                    (unsigned long long) aAddress,
+                                                    kCSNow);
+  }
+
+  if (!CSIsNull(owner)) {
+    ownerName = CSSymbolOwnerGetName(owner);
+  }
+
+  snprintf(retval, MAXPATHLEN, "%s", ownerName);
+  ReleaseSymbolicator();
+
+  return retval;
+}
+
+char*
+nsCocoaDebugUtils::GetAddressString(void* aAddress)
+{
+  return GetAddressStringInt(aAddress);
+}
+
+char*
+nsCocoaDebugUtils::GetAddressStringInt(void* aAddress, CSTypeRef aOwner)
+{
+  char* retval = (char*) calloc(MAXPATHLEN, 1);
+
+  const char* addressName = "unknown";
+  unsigned long long addressOffset = 0;
+
+  CSSymbolicatorRef symbolicator = GetSymbolicatorRef();
+  CSTypeRef owner = aOwner;
+
+  if (CSIsNull(owner) && !CSIsNull(symbolicator)) {
+    owner =
+      CSSymbolicatorGetSymbolOwnerWithAddressAtTime(symbolicator,
+                                                    (unsigned long long) aAddress,
+                                                    kCSNow);
+  }
+
+  if (!CSIsNull(owner)) {
+    CSSymbolRef symbol =
+      CSSymbolOwnerGetSymbolWithAddress(owner,
+                                        (unsigned long long) aAddress);
+    if (!CSIsNull(symbol)) {
+      addressName = CSSymbolGetName(symbol);
+      CSRange range = CSSymbolGetRange(symbol);
+      addressOffset = (unsigned long long) aAddress - range.location;
+    } else {
+      addressOffset = (unsigned long long)
+        aAddress - CSSymbolOwnerGetBaseAddress(owner);
+    }
+  }
+
+  snprintf(retval, MAXPATHLEN, "%s + 0x%llx",
+           addressName, addressOffset);
+  ReleaseSymbolicator();
+
+  return retval;
+}
+
+CSSymbolicatorRef
+nsCocoaDebugUtils::GetSymbolicatorRef()
+{
+  if (CSIsNull(sSymbolicator)) {
+    // 0x40e0000 is the value returned by
+    // uint32_t CSSymbolicatorGetFlagsForNListOnlyData(void).  We don't use
+    // this method directly because it doesn't exist on OS X 10.6.  Unless
+    // we limit ourselves to NList data, it will take too long to get a
+    // stack trace where Dwarf debugging info is available (about 15 seconds
+    // with Firefox).  This means we won't be able to get a CSSourceInfoRef,
+    // or line number information.  Oh well.
+    sSymbolicator =
+      CSSymbolicatorCreateWithPidFlagsAndNotification(getpid(),
+                                                      0x40e0000, 0);
+  }
+  // Retaining just after creation prevents crashes when calling symbolicator
+  // code (for example from PrintStackTrace()) as Firefox is quitting.  Not
+  // sure why.  Doing this may mean that we leak sSymbolicator on quitting
+  // (if we ever created it).  No particular harm in that, though.
+  return CSRetain(sSymbolicator);
+}
+
+void
+nsCocoaDebugUtils::ReleaseSymbolicator()
+{
+  if (!CSIsNull(sSymbolicator)) {
+    CSRelease(sSymbolicator);
+  }
+}
diff --git a/widget/cocoa/nsCocoaFeatures.h b/widget/cocoa/nsCocoaFeatures.h
new file mode 100644
index 0000000000..a9cab95d56
--- /dev/null
+++ b/widget/cocoa/nsCocoaFeatures.h
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsCocoaFeatures_h_
+#define nsCocoaFeatures_h_
+
+#include <stdint.h>
+
+/// Note that this class assumes we support the platform we are running on.
+/// For better or worse, if the version is unknown or less than what we
+/// support, we set it to the minimum supported version.  GetSystemVersion
+/// is the only call that returns the unadjusted values.
+class nsCocoaFeatures {
+public:
+  static int32_t macOSVersion();
+  static int32_t macOSVersionMajor();
+  static int32_t macOSVersionMinor();
+  static int32_t macOSVersionBugFix();
+  static bool OnYosemiteOrLater();
+  static bool OnElCapitanOrLater();
+  static bool OnSierraOrLater();
+  static bool OnHighSierraOrLater();
+  static bool OnMojaveOrLater();
+  static bool OnCatalinaOrLater();
+  static bool OnBigSurOrLater();
+
+  static bool IsAtLeastVersion(int32_t aMajor, int32_t aMinor, int32_t aBugFix=0);
+
+  // These are utilities that do not change or depend on the value of mOSXVersion
+  // and instead just encapsulate the encoding algorithm.  Note that GetVersion
+  // actually adjusts to the lowest supported OS, so it will always return
+  // a "supported" version.  GetSystemVersion does not make any modifications.
+  static void GetSystemVersion(int &aMajor, int &aMinor, int &aBugFix);
+  static int32_t GetVersion(int32_t aMajor, int32_t aMinor, int32_t aBugFix);
+  static int32_t ExtractMajorVersion(int32_t aVersion);
+  static int32_t ExtractMinorVersion(int32_t aVersion);
+  static int32_t ExtractBugFixVersion(int32_t aVersion);
+
+private:
+  static void InitializeVersionNumbers();
+
+  static int32_t mOSVersion;
+};
+#endif // nsCocoaFeatures_h_
diff --git a/widget/cocoa/nsCocoaFeatures.mm b/widget/cocoa/nsCocoaFeatures.mm
new file mode 100644
index 0000000000..e0fafb7d96
--- /dev/null
+++ b/widget/cocoa/nsCocoaFeatures.mm
@@ -0,0 +1,209 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// This file makes some assumptions about the versions of macOS.
+// We are assuming that the major, minor and bugfix versions are each less than
+// 256.
+// There are MOZ_ASSERTs for that.
+
+// The formula for the version integer is (major << 16) + (minor << 8) + bugfix.
+
+#define MACOS_VERSION_MASK 0x00FFFFFF
+#define MACOS_MAJOR_VERSION_MASK 0x00FFFFFF
+#define MACOS_MINOR_VERSION_MASK 0x00FFFFFF
+#define MACOS_BUGFIX_VERSION_MASK 0x00FFFFFF
+#define MACOS_VERSION_10_0_HEX 0x000A0000
+#define MACOS_VERSION_10_7_HEX 0x000A0700
+#define MACOS_VERSION_10_8_HEX 0x000A0800
+#define MACOS_VERSION_10_9_HEX 0x000A0900
+#define MACOS_VERSION_10_10_HEX 0x000A0A00
+#define MACOS_VERSION_10_11_HEX 0x000A0B00
+#define MACOS_VERSION_10_12_HEX 0x000A0C00
+#define MACOS_VERSION_10_13_HEX 0x000A0D00
+#define MACOS_VERSION_10_14_HEX 0x000A0E00
+#define MACOS_VERSION_10_15_HEX 0x000A0F00
+#define MACOS_VERSION_10_16_HEX 0x000A1000
+#define MACOS_VERSION_11_0_HEX 0x000B0000
+
+#include "nsCocoaFeatures.h"
+#include "nsCocoaUtils.h"
+#include "nsDebug.h"
+#include "nsObjCExceptions.h"
+
+#import <Cocoa/Cocoa.h>
+
+int32_t nsCocoaFeatures::mOSVersion = 0;
+
+// This should not be called with unchecked aMajor, which should be >= 10.
+inline int32_t AssembleVersion(int32_t aMajor, int32_t aMinor, int32_t aBugFix)
+{
+  MOZ_ASSERT(aMajor >= 10);
+  return (aMajor << 16) + (aMinor << 8) + aBugFix;
+}
+
+int32_t nsCocoaFeatures::ExtractMajorVersion(int32_t aVersion)
+{
+  MOZ_ASSERT((aVersion & MACOS_VERSION_MASK) == aVersion);
+  return (aVersion & 0xFF0000) >> 16;
+}
+
+int32_t nsCocoaFeatures::ExtractMinorVersion(int32_t aVersion)
+{
+  MOZ_ASSERT((aVersion & MACOS_VERSION_MASK) == aVersion);
+  return (aVersion & 0xFF00) >> 8;
+}
+
+int32_t nsCocoaFeatures::ExtractBugFixVersion(int32_t aVersion)
+{
+  MOZ_ASSERT((aVersion & MACOS_VERSION_MASK) == aVersion);
+  return aVersion & 0xFF;
+}
+
+static int intAtStringIndex(NSArray *array, int index)
+{
+  return [(NSString*)[array objectAtIndex:index] integerValue];
+}
+
+void nsCocoaFeatures::GetSystemVersion(int &major, int &minor, int &bugfix)
+{
+    major = minor = bugfix = 0;
+
+    NSString* versionString = [[NSDictionary dictionaryWithContentsOfFile:
+                                @"/System/Library/CoreServices/SystemVersion.plist"] objectForKey:@"ProductVersion"];
+    NSArray* versions = [versionString componentsSeparatedByString:@"."];
+    NSUInteger count = [versions count];
+    if (count > 0) {
+        major = intAtStringIndex(versions, 0);
+        if (count > 1) {
+            minor = intAtStringIndex(versions, 1);
+            if (count > 2) {
+                bugfix = intAtStringIndex(versions, 2);
+            }
+        }
+    }
+}
+
+int32_t nsCocoaFeatures::GetVersion(int32_t aMajor, int32_t aMinor, int32_t aBugFix)
+{
+  int32_t macOSVersion;
+  if (aMajor < 10) {
+    aMajor = 10;
+    NS_ERROR("Couldn't determine macOS version, assuming 10.7");
+    macOSVersion = MACOS_VERSION_10_7_HEX;
+  } else if (aMajor == 10 && aMinor < 7) {
+    aMinor = 7;
+    NS_ERROR("macOS version too old, assuming 10.7");
+    macOSVersion = MACOS_VERSION_10_7_HEX;
+  } else {
+    MOZ_ASSERT(aMajor >= 10);
+    MOZ_ASSERT(aMajor < 256);
+    MOZ_ASSERT(aMinor >= 0);
+    MOZ_ASSERT(aMinor < 256);
+    MOZ_ASSERT(aBugFix >= 0);
+    MOZ_ASSERT(aBugFix < 256);
+    macOSVersion = AssembleVersion(aMajor, aMinor, aBugFix);
+  }
+  MOZ_ASSERT(aMajor == ExtractMajorVersion(macOSVersion));
+  MOZ_ASSERT(aMinor == ExtractMinorVersion(macOSVersion));
+  MOZ_ASSERT(aBugFix == ExtractBugFixVersion(macOSVersion));
+  return macOSVersion;
+}
+
+/*static*/ void
+nsCocoaFeatures::InitializeVersionNumbers()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Provide an autorelease pool to avoid leaking Cocoa objects,
+  // as this gets called before the main autorelease pool is in place.
+  nsAutoreleasePool localPool;
+
+  int major, minor, bugfix;
+  GetSystemVersion(major, minor, bugfix);
+  mOSVersion = GetVersion(major, minor, bugfix);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+/* static */ int32_t
+nsCocoaFeatures::macOSVersion()
+{
+  // Don't let this be called while we're first setting the value...
+  MOZ_ASSERT((mOSVersion & MACOS_VERSION_MASK) >= 0);
+  if (!mOSVersion) {
+    mOSVersion = -1;
+    InitializeVersionNumbers();
+  }
+  return mOSVersion;
+}
+
+/* static */ int32_t
+nsCocoaFeatures::macOSVersionMajor()
+{
+  return ExtractMajorVersion(macOSVersion());
+}
+
+/* static */ int32_t
+nsCocoaFeatures::macOSVersionMinor()
+{
+  return ExtractMinorVersion(macOSVersion());
+}
+
+/* static */ int32_t
+nsCocoaFeatures::macOSVersionBugFix()
+{
+  return ExtractBugFixVersion(macOSVersion());
+}
+
+/* static */ bool
+nsCocoaFeatures::OnYosemiteOrLater()
+{
+  return (macOSVersion() >= MACOS_VERSION_10_10_HEX);
+}
+
+/* static */ bool
+nsCocoaFeatures::OnElCapitanOrLater()
+{
+  return (macOSVersion() >= MACOS_VERSION_10_11_HEX);
+}
+
+/* static */ bool
+nsCocoaFeatures::OnSierraOrLater()
+{
+  return (macOSVersion() >= MACOS_VERSION_10_12_HEX);
+}
+
+/* static */ bool 
+nsCocoaFeatures::OnHighSierraOrLater() 
+{
+  return (macOSVersion() >= MACOS_VERSION_10_13_HEX);
+}
+
+/* static */ bool 
+nsCocoaFeatures::OnMojaveOrLater() 
+{
+  return (macOSVersion() >= MACOS_VERSION_10_14_HEX);
+}
+
+/* static */ bool 
+nsCocoaFeatures::OnCatalinaOrLater() 
+{
+  return (macOSVersion() >= MACOS_VERSION_10_15_HEX);
+}
+
+/* static */ bool
+nsCocoaFeatures::OnBigSurOrLater()
+{
+  // Account for the version being 10.16 (which occurs when the
+  // application is linked with an older SDK) or 11.0 on Big Sur.
+  return ((macOSVersion() >= MACOS_VERSION_10_16_HEX) ||
+          (macOSVersion() >= MACOS_VERSION_11_0_HEX));
+}
+
+/* static */ bool
+nsCocoaFeatures::IsAtLeastVersion(int32_t aMajor, int32_t aMinor, int32_t aBugFix)
+{
+    return macOSVersion() >= GetVersion(aMajor, aMinor, aBugFix);
+}
diff --git a/widget/cocoa/nsCocoaUtils.h b/widget/cocoa/nsCocoaUtils.h
new file mode 100644
index 0000000000..139e76b4ad
--- /dev/null
+++ b/widget/cocoa/nsCocoaUtils.h
@@ -0,0 +1,389 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsCocoaUtils_h_
+#define nsCocoaUtils_h_
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsRect.h"
+#include "imgIContainer.h"
+#include "npapi.h"
+#include "nsTArray.h"
+#include "Units.h"
+
+// This must be the last include:
+#include "nsObjCExceptions.h"
+
+#include "mozilla/EventForwards.h"
+
+// Declare the backingScaleFactor method that we want to call
+// on NSView/Window/Screen objects, if they recognize it.
+@interface NSObject (BackingScaleFactorCategory)
+- (CGFloat)backingScaleFactor;
+@end
+
+#if !defined(MAC_OS_X_VERSION_10_8) || MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_8
+enum {
+  NSEventPhaseMayBegin    = 0x1 << 5
+};
+#endif
+
+class nsIWidget;
+
+namespace mozilla {
+namespace gfx {
+class SourceSurface;
+} // namespace gfx
+} // namespace mozilla
+
+// Used to retain a Cocoa object for the remainder of a method's execution.
+class nsAutoRetainCocoaObject {
+public:
+explicit nsAutoRetainCocoaObject(id anObject)
+{
+  mObject = NS_OBJC_TRY_EXPR_ABORT([anObject retain]);
+}
+~nsAutoRetainCocoaObject()
+{
+  NS_OBJC_TRY_ABORT([mObject release]);
+}
+private:
+  id mObject;  // [STRONG]
+};
+
+// Provide a local autorelease pool for the remainder of a method's execution.
+class nsAutoreleasePool {
+public:
+  nsAutoreleasePool()
+  {
+    mLocalPool = [[NSAutoreleasePool alloc] init];
+  }
+  ~nsAutoreleasePool()
+  {
+    [mLocalPool release];
+  }
+private:
+  NSAutoreleasePool *mLocalPool;
+};
+
+@interface NSApplication (Undocumented)
+
+// Present in all versions of OS X from (at least) 10.2.8 through 10.5.
+- (BOOL)_isRunningModal;
+- (BOOL)_isRunningAppModal;
+
+// It's sometimes necessary to explicitly remove a window from the "window
+// cache" in order to deactivate it.  The "window cache" is an undocumented
+// subsystem, all of whose methods are included in the NSWindowCache category
+// of the NSApplication class (in header files generated using class-dump).
+// Present in all versions of OS X from (at least) 10.2.8 through 10.5.
+- (void)_removeWindowFromCache:(NSWindow *)aWindow;
+
+// Send an event to the current Cocoa app-modal session.  Present in all
+// versions of OS X from (at least) 10.2.8 through 10.5.
+- (void)_modalSession:(NSModalSession)aSession sendEvent:(NSEvent *)theEvent;
+
+@end
+
+struct KeyBindingsCommand
+{
+  SEL selector;
+  id data;
+};
+
+@interface NativeKeyBindingsRecorder : NSResponder
+{
+@private
+  nsTArray<KeyBindingsCommand>* mCommands;
+}
+
+- (void)startRecording:(nsTArray<KeyBindingsCommand>&)aCommands;
+
+- (void)doCommandBySelector:(SEL)aSelector;
+
+- (void)insertText:(id)aString;
+
+@end // NativeKeyBindingsRecorder
+
+class nsCocoaUtils
+{
+  typedef mozilla::gfx::SourceSurface SourceSurface;
+  typedef mozilla::LayoutDeviceIntPoint LayoutDeviceIntPoint;
+  typedef mozilla::LayoutDeviceIntRect LayoutDeviceIntRect;
+
+public:
+
+  // Get the backing scale factor from an object that supports this selector
+  // (NSView/Window/Screen, on 10.7 or later), returning 1.0 if not supported
+  static CGFloat
+  GetBackingScaleFactor(id aObject)
+  {
+    if (HiDPIEnabled() &&
+        [aObject respondsToSelector:@selector(backingScaleFactor)]) {
+      return [aObject backingScaleFactor];
+    }
+    return 1.0;
+  }
+
+  // Conversions between Cocoa points and device pixels, given the backing
+  // scale factor from a view/window/screen.
+  static int32_t
+  CocoaPointsToDevPixels(CGFloat aPts, CGFloat aBackingScale)
+  {
+    return NSToIntRound(aPts * aBackingScale);
+  }
+
+  static LayoutDeviceIntPoint
+  CocoaPointsToDevPixels(const NSPoint& aPt, CGFloat aBackingScale)
+  {
+    return LayoutDeviceIntPoint(NSToIntRound(aPt.x * aBackingScale),
+                                NSToIntRound(aPt.y * aBackingScale));
+  }
+
+  static LayoutDeviceIntPoint
+  CocoaPointsToDevPixelsRoundDown(const NSPoint& aPt, CGFloat aBackingScale)
+  {
+    return LayoutDeviceIntPoint(NSToIntFloor(aPt.x * aBackingScale),
+                                NSToIntFloor(aPt.y * aBackingScale));
+  }
+
+  static LayoutDeviceIntRect
+  CocoaPointsToDevPixels(const NSRect& aRect, CGFloat aBackingScale)
+  {
+    return LayoutDeviceIntRect(NSToIntRound(aRect.origin.x * aBackingScale),
+                               NSToIntRound(aRect.origin.y * aBackingScale),
+                               NSToIntRound(aRect.size.width * aBackingScale),
+                               NSToIntRound(aRect.size.height * aBackingScale));
+  }
+
+  static CGFloat
+  DevPixelsToCocoaPoints(int32_t aPixels, CGFloat aBackingScale)
+  {
+    return (CGFloat)aPixels / aBackingScale;
+  }
+
+  static NSPoint
+  DevPixelsToCocoaPoints(const mozilla::LayoutDeviceIntPoint& aPt,
+                         CGFloat aBackingScale)
+  {
+    return NSMakePoint((CGFloat)aPt.x / aBackingScale,
+                       (CGFloat)aPt.y / aBackingScale);
+  }
+
+  // Implements an NSPoint equivalent of -[NSWindow convertRectFromScreen:].
+  static NSPoint
+  ConvertPointFromScreen(NSWindow* aWindow, const NSPoint& aPt)
+  {
+    return [aWindow convertRectFromScreen:NSMakeRect(aPt.x, aPt.y, 0, 0)].origin;
+  }
+
+  // Implements an NSPoint equivalent of -[NSWindow convertRectToScreen:].
+  static NSPoint
+  ConvertPointToScreen(NSWindow* aWindow, const NSPoint& aPt)
+  {
+    return [aWindow convertRectToScreen:NSMakeRect(aPt.x, aPt.y, 0, 0)].origin;
+  }
+
+  static NSRect
+  DevPixelsToCocoaPoints(const LayoutDeviceIntRect& aRect,
+                         CGFloat aBackingScale)
+  {
+    return NSMakeRect((CGFloat)aRect.x / aBackingScale,
+                      (CGFloat)aRect.y / aBackingScale,
+                      (CGFloat)aRect.width / aBackingScale,
+                      (CGFloat)aRect.height / aBackingScale);
+  }
+
+  // Returns the given y coordinate, which must be in screen coordinates,
+  // flipped from Gecko to Cocoa or Cocoa to Gecko.
+  static float FlippedScreenY(float y);
+
+  // The following functions come in "DevPix" variants that work with
+  // backing-store (device pixel) coordinates, as well as the original
+  // versions that expect coordinates in Cocoa points/CSS pixels.
+  // The difference becomes important in HiDPI display modes, where Cocoa
+  // points and backing-store pixels are no longer 1:1.
+
+  // Gecko rects (nsRect) contain an origin (x,y) in a coordinate
+  // system with (0,0) in the top-left of the primary screen. Cocoa rects
+  // (NSRect) contain an origin (x,y) in a coordinate system with (0,0)
+  // in the bottom-left of the primary screen. Both nsRect and NSRect
+  // contain width/height info, with no difference in their use.
+  // This function does no scaling, so the Gecko coordinates are
+  // expected to be desktop pixels, which are equal to Cocoa points
+  // (by definition).
+  static NSRect GeckoRectToCocoaRect(const mozilla::DesktopIntRect &geckoRect);
+
+  // Converts aGeckoRect in dev pixels to points in Cocoa coordinates
+  static NSRect
+  GeckoRectToCocoaRectDevPix(const mozilla::LayoutDeviceIntRect &aGeckoRect,
+                             CGFloat aBackingScale);
+
+  // See explanation for geckoRectToCocoaRect, guess what this does...
+  static mozilla::DesktopIntRect CocoaRectToGeckoRect(const NSRect &cocoaRect);
+
+  static mozilla::LayoutDeviceIntRect CocoaRectToGeckoRectDevPix(
+    const NSRect& aCocoaRect, CGFloat aBackingScale);
+
+  // Gives the location for the event in screen coordinates. Do not call this
+  // unless the window the event was originally targeted at is still alive!
+  // anEvent may be nil -- in that case the current mouse location is returned.
+  static NSPoint ScreenLocationForEvent(NSEvent* anEvent);
+  
+  // Determines if an event happened over a window, whether or not the event
+  // is for the window. Does not take window z-order into account.
+  static BOOL IsEventOverWindow(NSEvent* anEvent, NSWindow* aWindow);
+
+  // Events are set up so that their coordinates refer to the window to which they
+  // were originally sent. If we reroute the event somewhere else, we'll have
+  // to get the window coordinates this way. Do not call this unless the window
+  // the event was originally targeted at is still alive!
+  static NSPoint EventLocationForWindow(NSEvent* anEvent, NSWindow* aWindow);
+
+  // Compatibility wrappers for the -[NSEvent phase], -[NSEvent momentumPhase],
+  // -[NSEvent hasPreciseScrollingDeltas] and -[NSEvent scrollingDeltaX/Y] APIs
+  // that became availaible starting with the 10.7 SDK.
+  // All of these can be removed once we drop support for 10.6.
+  static NSEventPhase EventPhase(NSEvent* aEvent);
+  static NSEventPhase EventMomentumPhase(NSEvent* aEvent);
+  static BOOL IsMomentumScrollEvent(NSEvent* aEvent);
+  static BOOL HasPreciseScrollingDeltas(NSEvent* aEvent);
+  static void GetScrollingDeltas(NSEvent* aEvent, CGFloat* aOutDeltaX, CGFloat* aOutDeltaY);
+  static BOOL EventHasPhaseInformation(NSEvent* aEvent);
+
+  // Hides the Menu bar and the Dock. Multiple hide/show requests can be nested.
+  static void HideOSChromeOnScreen(bool aShouldHide);
+
+  static nsIWidget* GetHiddenWindowWidget();
+
+  static void PrepareForNativeAppModalDialog();
+  static void CleanUpAfterNativeAppModalDialog();
+
+  // 3 utility functions to go from a frame of imgIContainer to CGImage and then to NSImage
+  // Convert imgIContainer -> CGImageRef, caller owns result
+  
+  /** Creates a <code>CGImageRef</code> from a frame contained in an <code>imgIContainer</code>.
+      Copies the pixel data from the indicated frame of the <code>imgIContainer</code> into a new <code>CGImageRef</code>.
+      The caller owns the <code>CGImageRef</code>. 
+      @param aFrame the frame to convert
+      @param aResult the resulting CGImageRef
+      @return NS_OK if the conversion worked, NS_ERROR_FAILURE otherwise
+   */
+  static nsresult CreateCGImageFromSurface(SourceSurface* aSurface,
+                                           CGImageRef* aResult);
+  
+  /** Creates a Cocoa <code>NSImage</code> from a <code>CGImageRef</code>.
+      Copies the pixel data from the <code>CGImageRef</code> into a new <code>NSImage</code>.
+      The caller owns the <code>NSImage</code>. 
+      @param aInputImage the image to convert
+      @param aResult the resulting NSImage
+      @return NS_OK if the conversion worked, NS_ERROR_FAILURE otherwise
+   */
+  static nsresult CreateNSImageFromCGImage(CGImageRef aInputImage, NSImage **aResult);
+
+  /** Creates a Cocoa <code>NSImage</code> from a frame of an <code>imgIContainer</code>.
+      Combines the two methods above. The caller owns the <code>NSImage</code>.
+      @param aImage the image to extract a frame from
+      @param aWhichFrame the frame to extract (see imgIContainer FRAME_*)
+      @param aResult the resulting NSImage
+      @param scaleFactor the desired scale factor of the NSImage (2 for a retina display)
+      @return NS_OK if the conversion worked, NS_ERROR_FAILURE otherwise
+   */  
+  static nsresult CreateNSImageFromImageContainer(imgIContainer *aImage, uint32_t aWhichFrame, NSImage **aResult, CGFloat scaleFactor);
+
+  /**
+   * Returns nsAString for aSrc.
+   */
+  static void GetStringForNSString(const NSString *aSrc, nsAString& aDist);
+
+  /**
+   * Makes NSString instance for aString.
+   */
+  static NSString* ToNSString(const nsAString& aString);
+
+  /**
+   * Returns NSRect for aGeckoRect.
+   * Just copies values between the two types; it does no coordinate-system
+   * conversion, so both rects must have the same coordinate origin/direction.
+   */
+  static void GeckoRectToNSRect(const nsIntRect& aGeckoRect,
+                                NSRect& aOutCocoaRect);
+
+  /**
+   * Returns Gecko rect for aCocoaRect.
+   * Just copies values between the two types; it does no coordinate-system
+   * conversion, so both rects must have the same coordinate origin/direction.
+   */
+  static void NSRectToGeckoRect(const NSRect& aCocoaRect,
+                                nsIntRect& aOutGeckoRect);
+
+  /**
+   * Makes NSEvent instance for aEventTytpe and aEvent.
+   */
+  static NSEvent* MakeNewCocoaEventWithType(NSEventType aEventType,
+                                            NSEvent *aEvent);
+
+  /**
+   * Initializes aNPCocoaEvent.
+   */
+  static void InitNPCocoaEvent(NPCocoaEvent* aNPCocoaEvent);
+
+  /**
+   * Initializes WidgetInputEvent for aNativeEvent or aModifiers.
+   */
+  static void InitInputEvent(mozilla::WidgetInputEvent &aInputEvent,
+                             NSEvent* aNativeEvent);
+
+  /**
+   * Converts the native modifiers from aNativeEvent into WidgetMouseEvent
+   * Modifiers. aNativeEvent can be null.
+   */
+  static mozilla::Modifiers ModifiersForEvent(NSEvent* aNativeEvent);
+
+  /**
+   * ConvertToCarbonModifier() returns carbon modifier flags for the cocoa
+   * modifier flags.
+   * NOTE: The result never includes right*Key.
+   */
+  static UInt32 ConvertToCarbonModifier(NSUInteger aCocoaModifier);
+
+  /**
+   * Whether to support HiDPI rendering. For testing purposes, to be removed
+   * once we're comfortable with the HiDPI behavior.
+   */
+  static bool HiDPIEnabled();
+
+  /**
+   * Keys can optionally be bound by system or user key bindings to one or more
+   * commands based on selectors. This collects any such commands in the
+   * provided array.
+   */
+  static void GetCommandsFromKeyEvent(NSEvent* aEvent,
+                                      nsTArray<KeyBindingsCommand>& aCommands);
+
+  /**
+   * Converts the string name of a Gecko key (like "VK_HOME") to the
+   * corresponding Cocoa Unicode character.
+   */
+  static uint32_t ConvertGeckoNameToMacCharCode(const nsAString& aKeyCodeName);
+
+  /**
+   * Converts a Gecko key code (like NS_VK_HOME) to the corresponding Cocoa
+   * Unicode character.
+   */
+  static uint32_t ConvertGeckoKeyCodeToMacCharCode(uint32_t aKeyCode);
+
+  /**
+   * Convert string with font attribute to NSMutableAttributedString
+   */
+  static NSMutableAttributedString* GetNSMutableAttributedString(
+           const nsAString& aText,
+           const nsTArray<mozilla::FontRange>& aFontRanges,
+           const bool aIsVertical,
+           const CGFloat aBackingScaleFactor);
+};
+
+#endif // nsCocoaUtils_h_
diff --git a/widget/cocoa/nsCocoaUtils.mm b/widget/cocoa/nsCocoaUtils.mm
new file mode 100644
index 0000000000..3138245aa7
--- /dev/null
+++ b/widget/cocoa/nsCocoaUtils.mm
@@ -0,0 +1,1022 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <cmath>
+
+#include "gfx2DGlue.h"
+#include "gfxPlatform.h"
+#include "gfxUtils.h"
+#include "ImageRegion.h"
+#include "nsCocoaUtils.h"
+#include "nsChildView.h"
+#include "nsMenuBarX.h"
+#include "nsCocoaWindow.h"
+#include "nsCOMPtr.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIAppShellService.h"
+#include "nsIXULWindow.h"
+#include "nsIBaseWindow.h"
+#include "nsIServiceManager.h"
+#include "nsMenuUtilsX.h"
+#include "nsToolkit.h"
+#include "nsCRT.h"
+#include "SVGImageContext.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/MiscEvents.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/TextEvents.h"
+
+using namespace mozilla;
+using namespace mozilla::widget;
+
+using mozilla::gfx::BackendType;
+using mozilla::gfx::DataSourceSurface;
+using mozilla::gfx::DrawTarget;
+using mozilla::gfx::Factory;
+using mozilla::gfx::SamplingFilter;
+using mozilla::gfx::IntPoint;
+using mozilla::gfx::IntRect;
+using mozilla::gfx::IntSize;
+using mozilla::gfx::SurfaceFormat;
+using mozilla::gfx::SourceSurface;
+using mozilla::image::ImageRegion;
+using std::ceil;
+
+static float
+MenuBarScreenHeight()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NSArray* allScreens = [NSScreen screens];
+  if ([allScreens count]) {
+    return [[allScreens objectAtIndex:0] frame].size.height;
+  }
+
+  return 0.0;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0.0);
+}
+
+float
+nsCocoaUtils::FlippedScreenY(float y)
+{
+  return MenuBarScreenHeight() - y;
+}
+
+NSRect nsCocoaUtils::GeckoRectToCocoaRect(const DesktopIntRect &geckoRect)
+{
+  // We only need to change the Y coordinate by starting with the primary screen
+  // height and subtracting the gecko Y coordinate of the bottom of the rect.
+  return NSMakeRect(geckoRect.x,
+                    MenuBarScreenHeight() - geckoRect.YMost(),
+                    geckoRect.width,
+                    geckoRect.height);
+}
+
+NSRect
+nsCocoaUtils::GeckoRectToCocoaRectDevPix(const LayoutDeviceIntRect &aGeckoRect,
+                                         CGFloat aBackingScale)
+{
+  return NSMakeRect(aGeckoRect.x / aBackingScale,
+                    MenuBarScreenHeight() - aGeckoRect.YMost() / aBackingScale,
+                    aGeckoRect.width / aBackingScale,
+                    aGeckoRect.height / aBackingScale);
+}
+
+DesktopIntRect nsCocoaUtils::CocoaRectToGeckoRect(const NSRect &cocoaRect)
+{
+  // We only need to change the Y coordinate by starting with the primary screen
+  // height and subtracting both the cocoa y origin and the height of the
+  // cocoa rect.
+  DesktopIntRect rect;
+  rect.x = NSToIntRound(cocoaRect.origin.x);
+  rect.y = NSToIntRound(FlippedScreenY(cocoaRect.origin.y + cocoaRect.size.height));
+  rect.width = NSToIntRound(cocoaRect.origin.x + cocoaRect.size.width) - rect.x;
+  rect.height = NSToIntRound(FlippedScreenY(cocoaRect.origin.y)) - rect.y;
+  return rect;
+}
+
+LayoutDeviceIntRect nsCocoaUtils::CocoaRectToGeckoRectDevPix(
+  const NSRect& aCocoaRect, CGFloat aBackingScale)
+{
+  LayoutDeviceIntRect rect;
+  rect.x = NSToIntRound(aCocoaRect.origin.x * aBackingScale);
+  rect.y = NSToIntRound(FlippedScreenY(aCocoaRect.origin.y + aCocoaRect.size.height) * aBackingScale);
+  rect.width = NSToIntRound((aCocoaRect.origin.x + aCocoaRect.size.width) * aBackingScale) - rect.x;
+  rect.height = NSToIntRound(FlippedScreenY(aCocoaRect.origin.y) * aBackingScale) - rect.y;
+  return rect;
+}
+
+NSPoint nsCocoaUtils::ScreenLocationForEvent(NSEvent* anEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  // Don't trust mouse locations of mouse move events, see bug 443178.
+  if (!anEvent || [anEvent type] == NSMouseMoved)
+    return [NSEvent mouseLocation];
+
+  // Pin momentum scroll events to the location of the last user-controlled
+  // scroll event.
+  if (IsMomentumScrollEvent(anEvent))
+    return ChildViewMouseTracker::sLastScrollEventScreenLocation;
+
+  return nsCocoaUtils::ConvertPointToScreen([anEvent window], [anEvent locationInWindow]);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSMakePoint(0.0, 0.0));
+}
+
+BOOL nsCocoaUtils::IsEventOverWindow(NSEvent* anEvent, NSWindow* aWindow)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return NSPointInRect(ScreenLocationForEvent(anEvent), [aWindow frame]);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+NSPoint nsCocoaUtils::EventLocationForWindow(NSEvent* anEvent, NSWindow* aWindow)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return nsCocoaUtils::ConvertPointFromScreen(aWindow, ScreenLocationForEvent(anEvent));
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NSMakePoint(0.0, 0.0));
+}
+
+@interface NSEvent (ScrollPhase)
+// 10.5 and 10.6
+- (long long)_scrollPhase;
+// 10.7 and above
+- (NSEventPhase)phase;
+- (NSEventPhase)momentumPhase;
+@end
+
+NSEventPhase nsCocoaUtils::EventPhase(NSEvent* aEvent)
+{
+  if ([aEvent respondsToSelector:@selector(phase)]) {
+    return [aEvent phase];
+  }
+  return NSEventPhaseNone;
+}
+
+NSEventPhase nsCocoaUtils::EventMomentumPhase(NSEvent* aEvent)
+{
+  if ([aEvent respondsToSelector:@selector(momentumPhase)]) {
+    return [aEvent momentumPhase];
+  }
+  if ([aEvent respondsToSelector:@selector(_scrollPhase)]) {
+    switch ([aEvent _scrollPhase]) {
+      case 1: return NSEventPhaseBegan;
+      case 2: return NSEventPhaseChanged;
+      case 3: return NSEventPhaseEnded;
+      default: return NSEventPhaseNone;
+    }
+  }
+  return NSEventPhaseNone;
+}
+
+BOOL nsCocoaUtils::IsMomentumScrollEvent(NSEvent* aEvent)
+{
+  return [aEvent type] == NSScrollWheel &&
+    EventMomentumPhase(aEvent) != NSEventPhaseNone;
+}
+
+@interface NSEvent (HasPreciseScrollingDeltas)
+// 10.7 and above
+- (BOOL)hasPreciseScrollingDeltas;
+// For 10.6 and below, see the comment in nsChildView.h about _eventRef
+- (EventRef)_eventRef;
+@end
+
+BOOL nsCocoaUtils::HasPreciseScrollingDeltas(NSEvent* aEvent)
+{
+  if ([aEvent respondsToSelector:@selector(hasPreciseScrollingDeltas)]) {
+    return [aEvent hasPreciseScrollingDeltas];
+  }
+
+  // For events that don't contain pixel scrolling information, the event
+  // kind of their underlaying carbon event is kEventMouseWheelMoved instead
+  // of kEventMouseScroll.
+  EventRef carbonEvent = [aEvent _eventRef];
+  return carbonEvent && ::GetEventKind(carbonEvent) == kEventMouseScroll;
+}
+
+@interface NSEvent (ScrollingDeltas)
+// 10.6 and below
+- (CGFloat)deviceDeltaX;
+- (CGFloat)deviceDeltaY;
+// 10.7 and above
+- (CGFloat)scrollingDeltaX;
+- (CGFloat)scrollingDeltaY;
+@end
+
+void nsCocoaUtils::GetScrollingDeltas(NSEvent* aEvent, CGFloat* aOutDeltaX, CGFloat* aOutDeltaY)
+{
+  if ([aEvent respondsToSelector:@selector(scrollingDeltaX)]) {
+    *aOutDeltaX = [aEvent scrollingDeltaX];
+    *aOutDeltaY = [aEvent scrollingDeltaY];
+    return;
+  }
+  if ([aEvent respondsToSelector:@selector(deviceDeltaX)] &&
+      HasPreciseScrollingDeltas(aEvent)) {
+    // Calling deviceDeltaX/Y on those events that do not contain pixel
+    // scrolling information triggers a Cocoa assertion and an
+    // Objective-C NSInternalInconsistencyException.
+    *aOutDeltaX = [aEvent deviceDeltaX];
+    *aOutDeltaY = [aEvent deviceDeltaY];
+    return;
+  }
+
+  // This is only hit pre-10.7 when we are called on a scroll event that does
+  // not contain pixel scrolling information.
+  CGFloat lineDeltaPixels = 12;
+  *aOutDeltaX = [aEvent deltaX] * lineDeltaPixels;
+  *aOutDeltaY = [aEvent deltaY] * lineDeltaPixels;
+}
+
+BOOL nsCocoaUtils::EventHasPhaseInformation(NSEvent* aEvent)
+{
+  if (![aEvent respondsToSelector:@selector(phase)]) {
+    return NO;
+  }
+  return EventPhase(aEvent) != NSEventPhaseNone ||
+         EventMomentumPhase(aEvent) != NSEventPhaseNone;
+}
+
+void nsCocoaUtils::HideOSChromeOnScreen(bool aShouldHide)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Keep track of how many hiding requests have been made, so that they can
+  // be nested.
+  static int sHiddenCount = 0;
+
+  sHiddenCount += aShouldHide ? 1 : -1;
+  NS_ASSERTION(sHiddenCount >= 0, "Unbalanced HideMenuAndDockForWindow calls");
+
+  NSApplicationPresentationOptions options =
+    sHiddenCount <= 0 ? NSApplicationPresentationDefault :
+    NSApplicationPresentationHideDock | NSApplicationPresentationHideMenuBar;
+  [NSApp setPresentationOptions:options];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+#define NS_APPSHELLSERVICE_CONTRACTID "@mozilla.org/appshell/appShellService;1"
+nsIWidget* nsCocoaUtils::GetHiddenWindowWidget()
+{
+  nsCOMPtr<nsIAppShellService> appShell(do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+  if (!appShell) {
+    NS_WARNING("Couldn't get AppShellService in order to get hidden window ref");
+    return nullptr;
+  }
+  
+  nsCOMPtr<nsIXULWindow> hiddenWindow;
+  appShell->GetHiddenWindow(getter_AddRefs(hiddenWindow));
+  if (!hiddenWindow) {
+    // Don't warn, this happens during shutdown, bug 358607.
+    return nullptr;
+  }
+  
+  nsCOMPtr<nsIBaseWindow> baseHiddenWindow;
+  baseHiddenWindow = do_GetInterface(hiddenWindow);
+  if (!baseHiddenWindow) {
+    NS_WARNING("Couldn't get nsIBaseWindow from hidden window (nsIXULWindow)");
+    return nullptr;
+  }
+  
+  nsCOMPtr<nsIWidget> hiddenWindowWidget;
+  if (NS_FAILED(baseHiddenWindow->GetMainWidget(getter_AddRefs(hiddenWindowWidget)))) {
+    NS_WARNING("Couldn't get nsIWidget from hidden window (nsIBaseWindow)");
+    return nullptr;
+  }
+  
+  return hiddenWindowWidget;
+}
+
+void nsCocoaUtils::PrepareForNativeAppModalDialog()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Don't do anything if this is embedding. We'll assume that if there is no hidden
+  // window we shouldn't do anything, and that should cover the embedding case.
+  nsMenuBarX* hiddenWindowMenuBar = nsMenuUtilsX::GetHiddenWindowMenuBar();
+  if (!hiddenWindowMenuBar)
+    return;
+
+  // First put up the hidden window menu bar so that app menu event handling is correct.
+  hiddenWindowMenuBar->Paint();
+
+  NSMenu* mainMenu = [NSApp mainMenu];
+  NS_ASSERTION([mainMenu numberOfItems] > 0, "Main menu does not have any items, something is terribly wrong!");
+  
+  // Create new menu bar for use with modal dialog
+  NSMenu* newMenuBar = [[NSMenu alloc] initWithTitle:@""];
+  
+  // Swap in our app menu. Note that the event target is whatever window is up when
+  // the app modal dialog goes up.
+  NSMenuItem* firstMenuItem = [[mainMenu itemAtIndex:0] retain];
+  [mainMenu removeItemAtIndex:0];
+  [newMenuBar insertItem:firstMenuItem atIndex:0];
+  [firstMenuItem release];
+  
+  // Add standard edit menu
+  [newMenuBar addItem:nsMenuUtilsX::GetStandardEditMenuItem()];
+  
+  // Show the new menu bar
+  [NSApp setMainMenu:newMenuBar];
+  [newMenuBar release];
+  
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaUtils::CleanUpAfterNativeAppModalDialog()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Don't do anything if this is embedding. We'll assume that if there is no hidden
+  // window we shouldn't do anything, and that should cover the embedding case.
+  nsMenuBarX* hiddenWindowMenuBar = nsMenuUtilsX::GetHiddenWindowMenuBar();
+  if (!hiddenWindowMenuBar)
+    return;
+
+  NSWindow* mainWindow = [NSApp mainWindow];
+  if (!mainWindow)
+    hiddenWindowMenuBar->Paint();
+  else
+    [WindowDelegate paintMenubarForWindow:mainWindow];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void data_ss_release_callback(void *aDataSourceSurface,
+                              const void *data,
+                              size_t size)
+{
+  if (aDataSourceSurface) {
+    static_cast<DataSourceSurface*>(aDataSourceSurface)->Unmap();
+    static_cast<DataSourceSurface*>(aDataSourceSurface)->Release();
+  }
+}
+
+nsresult nsCocoaUtils::CreateCGImageFromSurface(SourceSurface* aSurface,
+                                                CGImageRef* aResult)
+{
+  RefPtr<DataSourceSurface> dataSurface;
+
+  if (aSurface->GetFormat() ==  SurfaceFormat::B8G8R8A8) {
+    dataSurface = aSurface->GetDataSurface();
+  } else {
+    // CGImageCreate only supports 16- and 32-bit bit-depth
+    // Convert format to SurfaceFormat::B8G8R8A8
+    dataSurface = gfxUtils::
+      CopySurfaceToDataSourceSurfaceWithFormat(aSurface,
+                                               SurfaceFormat::B8G8R8A8);
+  }
+
+  NS_ENSURE_TRUE(dataSurface, NS_ERROR_FAILURE);
+
+  int32_t width = dataSurface->GetSize().width;
+  int32_t height = dataSurface->GetSize().height;
+  if (height < 1 || width < 1) {
+    return NS_ERROR_FAILURE;
+  }
+
+  DataSourceSurface::MappedSurface map;
+  if (!dataSurface->Map(DataSourceSurface::MapType::READ, &map)) {
+    return NS_ERROR_FAILURE;
+  }
+  // The Unmap() call happens in data_ss_release_callback
+
+  // Create a CGImageRef with the bits from the image, taking into account
+  // the alpha ordering and endianness of the machine so we don't have to
+  // touch the bits ourselves.
+  CGDataProviderRef dataProvider = ::CGDataProviderCreateWithData(dataSurface.forget().take(),
+                                                                  map.mData,
+                                                                  map.mStride * height,
+                                                                  data_ss_release_callback);
+  CGColorSpaceRef colorSpace = ::CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);
+  *aResult = ::CGImageCreate(width,
+                             height,
+                             8,
+                             32,
+                             map.mStride,
+                             colorSpace,
+                             kCGBitmapByteOrder32Host | kCGImageAlphaPremultipliedFirst,
+                             dataProvider,
+                             NULL,
+                             0,
+                             kCGRenderingIntentDefault);
+  ::CGColorSpaceRelease(colorSpace);
+  ::CGDataProviderRelease(dataProvider);
+  return *aResult ? NS_OK : NS_ERROR_FAILURE;
+}
+
+nsresult nsCocoaUtils::CreateNSImageFromCGImage(CGImageRef aInputImage, NSImage **aResult)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // Be very careful when creating the NSImage that the backing NSImageRep is
+  // exactly 1:1 with the input image. On a retina display, both [NSImage
+  // lockFocus] and [NSImage initWithCGImage:size:] will create an image with a
+  // 2x backing NSImageRep. This prevents NSCursor from recognizing a retina
+  // cursor, which only occurs if pixelsWide and pixelsHigh are exactly 2x the
+  // size of the NSImage.
+  //
+  // For example, if a 32x32 SVG cursor is rendered on a retina display, then
+  // aInputImage will be 64x64. The resulting NSImage will be scaled back down
+  // to 32x32 so it stays the correct size on the screen by changing its size
+  // (resizing a NSImage only scales the image and doesn't resample the data).
+  // If aInputImage is converted using [NSImage initWithCGImage:size:] then the
+  // bitmap will be 128x128 and NSCursor won't recognize a retina cursor, since
+  // it will expect a 64x64 bitmap.
+
+  int32_t width = ::CGImageGetWidth(aInputImage);
+  int32_t height = ::CGImageGetHeight(aInputImage);
+  NSRect imageRect = ::NSMakeRect(0.0, 0.0, width, height);
+
+  NSBitmapImageRep *offscreenRep = [[NSBitmapImageRep alloc]
+    initWithBitmapDataPlanes:NULL
+    pixelsWide:width
+    pixelsHigh:height
+    bitsPerSample:8
+    samplesPerPixel:4
+    hasAlpha:YES
+    isPlanar:NO
+    colorSpaceName:NSDeviceRGBColorSpace
+    bitmapFormat:NSAlphaFirstBitmapFormat
+    bytesPerRow:0
+    bitsPerPixel:0];
+
+  NSGraphicsContext *context = [NSGraphicsContext graphicsContextWithBitmapImageRep:offscreenRep];
+  [NSGraphicsContext saveGraphicsState];
+  [NSGraphicsContext setCurrentContext:context];
+
+  // Get the Quartz context and draw.
+  CGContextRef imageContext = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
+  ::CGContextDrawImage(imageContext, *(CGRect*)&imageRect, aInputImage);
+
+  [NSGraphicsContext restoreGraphicsState];
+
+  *aResult = [[NSImage alloc] initWithSize:NSMakeSize(width, height)];
+  [*aResult addRepresentation:offscreenRep];
+  [offscreenRep release];
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult nsCocoaUtils::CreateNSImageFromImageContainer(imgIContainer *aImage, uint32_t aWhichFrame, NSImage **aResult, CGFloat scaleFactor)
+{
+  RefPtr<SourceSurface> surface;
+  int32_t width = 0, height = 0;
+  aImage->GetWidth(&width);
+  aImage->GetHeight(&height);
+
+  // Render a vector image at the correct resolution on a retina display
+  if (aImage->GetType() == imgIContainer::TYPE_VECTOR && scaleFactor != 1.0f) {
+    IntSize scaledSize = IntSize::Ceil(width * scaleFactor, height * scaleFactor);
+
+    RefPtr<DrawTarget> drawTarget = gfxPlatform::GetPlatform()->
+      CreateOffscreenContentDrawTarget(scaledSize, SurfaceFormat::B8G8R8A8);
+    if (!drawTarget || !drawTarget->IsValid()) {
+      NS_ERROR("Failed to create valid DrawTarget");
+      return NS_ERROR_FAILURE;
+    }
+
+    RefPtr<gfxContext> context = gfxContext::CreateOrNull(drawTarget);
+    MOZ_ASSERT(context);
+
+    mozilla::image::DrawResult res =
+      aImage->Draw(context, scaledSize, ImageRegion::Create(scaledSize),
+                   aWhichFrame, SamplingFilter::POINT,
+                   /* no SVGImageContext */ Nothing(),
+                   imgIContainer::FLAG_SYNC_DECODE);
+
+    if (res != mozilla::image::DrawResult::SUCCESS) {
+      return NS_ERROR_FAILURE;
+    }
+
+    surface = drawTarget->Snapshot();
+  } else {
+    surface = aImage->GetFrame(aWhichFrame, imgIContainer::FLAG_SYNC_DECODE);
+  }
+
+  NS_ENSURE_TRUE(surface, NS_ERROR_FAILURE);
+
+  CGImageRef imageRef = NULL;
+  nsresult rv = nsCocoaUtils::CreateCGImageFromSurface(surface, &imageRef);
+  if (NS_FAILED(rv) || !imageRef) {
+    return NS_ERROR_FAILURE;
+  }
+
+  rv = nsCocoaUtils::CreateNSImageFromCGImage(imageRef, aResult);
+  if (NS_FAILED(rv) || !aResult) {
+    return NS_ERROR_FAILURE;
+  }
+  ::CGImageRelease(imageRef);
+
+  // Ensure the image will be rendered the correct size on a retina display
+  NSSize size = NSMakeSize(width, height);
+  [*aResult setSize:size];
+  [[[*aResult representations] objectAtIndex:0] setSize:size];
+  return NS_OK;
+}
+
+// static
+void
+nsCocoaUtils::GetStringForNSString(const NSString *aSrc, nsAString& aDist)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!aSrc) {
+    aDist.Truncate();
+    return;
+  }
+
+  aDist.SetLength([aSrc length]);
+  [aSrc getCharacters: reinterpret_cast<unichar*>(aDist.BeginWriting())];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// static
+NSString*
+nsCocoaUtils::ToNSString(const nsAString& aString)
+{
+  if (aString.IsEmpty()) {
+    return [NSString string];
+  }
+  return [NSString stringWithCharacters:reinterpret_cast<const unichar*>(aString.BeginReading())
+                                 length:aString.Length()];
+}
+
+// static
+void
+nsCocoaUtils::GeckoRectToNSRect(const nsIntRect& aGeckoRect,
+                                NSRect& aOutCocoaRect)
+{
+  aOutCocoaRect.origin.x = aGeckoRect.x;
+  aOutCocoaRect.origin.y = aGeckoRect.y;
+  aOutCocoaRect.size.width = aGeckoRect.width;
+  aOutCocoaRect.size.height = aGeckoRect.height;
+}
+
+// static
+void
+nsCocoaUtils::NSRectToGeckoRect(const NSRect& aCocoaRect,
+                                nsIntRect& aOutGeckoRect)
+{
+  aOutGeckoRect.x = NSToIntRound(aCocoaRect.origin.x);
+  aOutGeckoRect.y = NSToIntRound(aCocoaRect.origin.y);
+  aOutGeckoRect.width = NSToIntRound(aCocoaRect.origin.x + aCocoaRect.size.width) - aOutGeckoRect.x;
+  aOutGeckoRect.height = NSToIntRound(aCocoaRect.origin.y + aCocoaRect.size.height) - aOutGeckoRect.y;
+}
+
+// static
+NSEvent*
+nsCocoaUtils::MakeNewCocoaEventWithType(NSEventType aEventType, NSEvent *aEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSEvent* newEvent =
+    [NSEvent     keyEventWithType:aEventType
+                         location:[aEvent locationInWindow] 
+                    modifierFlags:[aEvent modifierFlags]
+                        timestamp:[aEvent timestamp]
+                     windowNumber:[aEvent windowNumber]
+                          context:[aEvent context]
+                       characters:[aEvent characters]
+      charactersIgnoringModifiers:[aEvent charactersIgnoringModifiers]
+                        isARepeat:[aEvent isARepeat]
+                          keyCode:[aEvent keyCode]];
+  return newEvent;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+// static
+void
+nsCocoaUtils::InitNPCocoaEvent(NPCocoaEvent* aNPCocoaEvent)
+{
+  memset(aNPCocoaEvent, 0, sizeof(NPCocoaEvent));
+}
+
+// static
+void
+nsCocoaUtils::InitInputEvent(WidgetInputEvent& aInputEvent,
+                             NSEvent* aNativeEvent)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  aInputEvent.mModifiers = ModifiersForEvent(aNativeEvent);
+  aInputEvent.mTime = PR_IntervalNow();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// static
+Modifiers
+nsCocoaUtils::ModifiersForEvent(NSEvent* aNativeEvent)
+{
+  NSUInteger modifiers =
+    aNativeEvent ? [aNativeEvent modifierFlags] : [NSEvent modifierFlags];
+  Modifiers result = 0;
+  if (modifiers & NSShiftKeyMask) {
+    result |= MODIFIER_SHIFT;
+  }
+  if (modifiers & NSControlKeyMask) {
+    result |= MODIFIER_CONTROL;
+  }
+  if (modifiers & NSAlternateKeyMask) {
+    result |= MODIFIER_ALT;
+    // Mac's option key is similar to other platforms' AltGr key.
+    // Let's set AltGr flag when option key is pressed for consistency with
+    // other platforms.
+    result |= MODIFIER_ALTGRAPH;
+  }
+  if (modifiers & NSCommandKeyMask) {
+    result |= MODIFIER_META;
+  }
+
+  if (modifiers & NSAlphaShiftKeyMask) {
+    result |= MODIFIER_CAPSLOCK;
+  }
+  // Mac doesn't have NumLock key.  We can assume that NumLock is always locked
+  // if user is using a keyboard which has numpad.  Otherwise, if user is using
+  // a keyboard which doesn't have numpad, e.g., MacBook's keyboard, we can
+  // assume that NumLock is always unlocked.
+  // Unfortunately, we cannot know whether current keyboard has numpad or not.
+  // We should notify locked state only when keys in numpad are pressed.
+  // By this, web applications may not be confused by unexpected numpad key's
+  // key event with unlocked state.
+  if (modifiers & NSNumericPadKeyMask) {
+    result |= MODIFIER_NUMLOCK;
+  }
+
+  // Be aware, NSFunctionKeyMask is included when arrow keys, home key or some
+  // other keys are pressed. We cannot check whether 'fn' key is pressed or
+  // not by the flag.
+
+  return result;
+}
+
+// static
+UInt32
+nsCocoaUtils::ConvertToCarbonModifier(NSUInteger aCocoaModifier)
+{
+  UInt32 carbonModifier = 0;
+  if (aCocoaModifier & NSAlphaShiftKeyMask) {
+    carbonModifier |= alphaLock;
+  }
+  if (aCocoaModifier & NSControlKeyMask) {
+    carbonModifier |= controlKey;
+  }
+  if (aCocoaModifier & NSAlternateKeyMask) {
+    carbonModifier |= optionKey;
+  }
+  if (aCocoaModifier & NSShiftKeyMask) {
+    carbonModifier |= shiftKey;
+  }
+  if (aCocoaModifier & NSCommandKeyMask) {
+    carbonModifier |= cmdKey;
+  }
+  if (aCocoaModifier & NSNumericPadKeyMask) {
+    carbonModifier |= kEventKeyModifierNumLockMask;
+  }
+  if (aCocoaModifier & NSFunctionKeyMask) {
+    carbonModifier |= kEventKeyModifierFnMask;
+  }
+  return carbonModifier;
+}
+
+// While HiDPI support is not 100% complete and tested, we'll have a pref
+// to allow it to be turned off in case of problems (or for testing purposes).
+
+// gfx.hidpi.enabled is an integer with the meaning:
+//    <= 0 : HiDPI support is disabled
+//       1 : HiDPI enabled provided all screens have the same backing resolution
+//     > 1 : HiDPI enabled even if there are a mixture of screen modes
+
+// All the following code is to be removed once HiDPI work is more complete.
+
+static bool sHiDPIEnabled = false;
+static bool sHiDPIPrefInitialized = false;
+
+// static
+bool
+nsCocoaUtils::HiDPIEnabled()
+{
+  if (!sHiDPIPrefInitialized) {
+    sHiDPIPrefInitialized = true;
+
+    int prefSetting = Preferences::GetInt("gfx.hidpi.enabled", 1);
+    if (prefSetting <= 0) {
+      return false;
+    }
+
+    // prefSetting is at least 1, need to check attached screens...
+
+    int scaleFactors = 0; // used as a bitset to track the screen types found
+    NSEnumerator *screenEnum = [[NSScreen screens] objectEnumerator];
+    while (NSScreen *screen = [screenEnum nextObject]) {
+      NSDictionary *desc = [screen deviceDescription];
+      if ([desc objectForKey:NSDeviceIsScreen] == nil) {
+        continue;
+      }
+      CGFloat scale =
+        [screen respondsToSelector:@selector(backingScaleFactor)] ?
+          [screen backingScaleFactor] : 1.0;
+      // Currently, we only care about differentiating "1.0" and "2.0",
+      // so we set one of the two low bits to record which.
+      if (scale > 1.0) {
+        scaleFactors |= 2;
+      } else {
+        scaleFactors |= 1;
+      }
+    }
+
+    // Now scaleFactors will be:
+    //   0 if no screens (supporting backingScaleFactor) found
+    //   1 if only lo-DPI screens
+    //   2 if only hi-DPI screens
+    //   3 if both lo- and hi-DPI screens
+    // We'll enable HiDPI support if there's only a single screen type,
+    // OR if the pref setting is explicitly greater than 1.
+    sHiDPIEnabled = (scaleFactors <= 2) || (prefSetting > 1);
+  }
+
+  return sHiDPIEnabled;
+}
+
+void
+nsCocoaUtils::GetCommandsFromKeyEvent(NSEvent* aEvent,
+                                      nsTArray<KeyBindingsCommand>& aCommands)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_ASSERT(aEvent);
+
+  static NativeKeyBindingsRecorder* sNativeKeyBindingsRecorder;
+  if (!sNativeKeyBindingsRecorder) {
+    sNativeKeyBindingsRecorder = [NativeKeyBindingsRecorder new];
+  }
+
+  [sNativeKeyBindingsRecorder startRecording:aCommands];
+
+  // This will trigger 0 - N calls to doCommandBySelector: and insertText:
+  [sNativeKeyBindingsRecorder
+    interpretKeyEvents:[NSArray arrayWithObject:aEvent]];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@implementation NativeKeyBindingsRecorder
+
+- (void)startRecording:(nsTArray<KeyBindingsCommand>&)aCommands
+{
+  mCommands = &aCommands;
+  mCommands->Clear();
+}
+
+- (void)doCommandBySelector:(SEL)aSelector
+{
+  KeyBindingsCommand command = {
+    aSelector,
+    nil
+  };
+
+  mCommands->AppendElement(command);
+}
+
+- (void)insertText:(id)aString
+{
+  KeyBindingsCommand command = {
+    @selector(insertText:),
+    aString
+  };
+
+  mCommands->AppendElement(command);
+}
+
+@end // NativeKeyBindingsRecorder
+
+struct KeyConversionData
+{
+  const char* str;
+  size_t strLength;
+  uint32_t geckoKeyCode;
+  uint32_t charCode;
+};
+
+static const KeyConversionData gKeyConversions[] = {
+
+#define KEYCODE_ENTRY(aStr, aCode) \
+  {#aStr, sizeof(#aStr) - 1, NS_##aStr, aCode}
+
+// Some keycodes may have different name in nsIDOMKeyEvent from its key name.
+#define KEYCODE_ENTRY2(aStr, aNSName, aCode) \
+  {#aStr, sizeof(#aStr) - 1, NS_##aNSName, aCode}
+
+  KEYCODE_ENTRY(VK_CANCEL, 0x001B),
+  KEYCODE_ENTRY(VK_DELETE, NSDeleteFunctionKey),
+  KEYCODE_ENTRY(VK_BACK, NSBackspaceCharacter),
+  KEYCODE_ENTRY2(VK_BACK_SPACE, VK_BACK, NSBackspaceCharacter),
+  KEYCODE_ENTRY(VK_TAB, NSTabCharacter),
+  KEYCODE_ENTRY(VK_CLEAR, NSClearLineFunctionKey),
+  KEYCODE_ENTRY(VK_RETURN, NSEnterCharacter),
+  KEYCODE_ENTRY(VK_SHIFT, 0),
+  KEYCODE_ENTRY(VK_CONTROL, 0),
+  KEYCODE_ENTRY(VK_ALT, 0),
+  KEYCODE_ENTRY(VK_PAUSE, NSPauseFunctionKey),
+  KEYCODE_ENTRY(VK_CAPS_LOCK, 0),
+  KEYCODE_ENTRY(VK_ESCAPE, 0),
+  KEYCODE_ENTRY(VK_SPACE, ' '),
+  KEYCODE_ENTRY(VK_PAGE_UP, NSPageUpFunctionKey),
+  KEYCODE_ENTRY(VK_PAGE_DOWN, NSPageDownFunctionKey),
+  KEYCODE_ENTRY(VK_END, NSEndFunctionKey),
+  KEYCODE_ENTRY(VK_HOME, NSHomeFunctionKey),
+  KEYCODE_ENTRY(VK_LEFT, NSLeftArrowFunctionKey),
+  KEYCODE_ENTRY(VK_UP, NSUpArrowFunctionKey),
+  KEYCODE_ENTRY(VK_RIGHT, NSRightArrowFunctionKey),
+  KEYCODE_ENTRY(VK_DOWN, NSDownArrowFunctionKey),
+  KEYCODE_ENTRY(VK_PRINTSCREEN, NSPrintScreenFunctionKey),
+  KEYCODE_ENTRY(VK_INSERT, NSInsertFunctionKey),
+  KEYCODE_ENTRY(VK_HELP, NSHelpFunctionKey),
+  KEYCODE_ENTRY(VK_0, '0'),
+  KEYCODE_ENTRY(VK_1, '1'),
+  KEYCODE_ENTRY(VK_2, '2'),
+  KEYCODE_ENTRY(VK_3, '3'),
+  KEYCODE_ENTRY(VK_4, '4'),
+  KEYCODE_ENTRY(VK_5, '5'),
+  KEYCODE_ENTRY(VK_6, '6'),
+  KEYCODE_ENTRY(VK_7, '7'),
+  KEYCODE_ENTRY(VK_8, '8'),
+  KEYCODE_ENTRY(VK_9, '9'),
+  KEYCODE_ENTRY(VK_SEMICOLON, ':'),
+  KEYCODE_ENTRY(VK_EQUALS, '='),
+  KEYCODE_ENTRY(VK_A, 'A'),
+  KEYCODE_ENTRY(VK_B, 'B'),
+  KEYCODE_ENTRY(VK_C, 'C'),
+  KEYCODE_ENTRY(VK_D, 'D'),
+  KEYCODE_ENTRY(VK_E, 'E'),
+  KEYCODE_ENTRY(VK_F, 'F'),
+  KEYCODE_ENTRY(VK_G, 'G'),
+  KEYCODE_ENTRY(VK_H, 'H'),
+  KEYCODE_ENTRY(VK_I, 'I'),
+  KEYCODE_ENTRY(VK_J, 'J'),
+  KEYCODE_ENTRY(VK_K, 'K'),
+  KEYCODE_ENTRY(VK_L, 'L'),
+  KEYCODE_ENTRY(VK_M, 'M'),
+  KEYCODE_ENTRY(VK_N, 'N'),
+  KEYCODE_ENTRY(VK_O, 'O'),
+  KEYCODE_ENTRY(VK_P, 'P'),
+  KEYCODE_ENTRY(VK_Q, 'Q'),
+  KEYCODE_ENTRY(VK_R, 'R'),
+  KEYCODE_ENTRY(VK_S, 'S'),
+  KEYCODE_ENTRY(VK_T, 'T'),
+  KEYCODE_ENTRY(VK_U, 'U'),
+  KEYCODE_ENTRY(VK_V, 'V'),
+  KEYCODE_ENTRY(VK_W, 'W'),
+  KEYCODE_ENTRY(VK_X, 'X'),
+  KEYCODE_ENTRY(VK_Y, 'Y'),
+  KEYCODE_ENTRY(VK_Z, 'Z'),
+  KEYCODE_ENTRY(VK_CONTEXT_MENU, NSMenuFunctionKey),
+  KEYCODE_ENTRY(VK_NUMPAD0, '0'),
+  KEYCODE_ENTRY(VK_NUMPAD1, '1'),
+  KEYCODE_ENTRY(VK_NUMPAD2, '2'),
+  KEYCODE_ENTRY(VK_NUMPAD3, '3'),
+  KEYCODE_ENTRY(VK_NUMPAD4, '4'),
+  KEYCODE_ENTRY(VK_NUMPAD5, '5'),
+  KEYCODE_ENTRY(VK_NUMPAD6, '6'),
+  KEYCODE_ENTRY(VK_NUMPAD7, '7'),
+  KEYCODE_ENTRY(VK_NUMPAD8, '8'),
+  KEYCODE_ENTRY(VK_NUMPAD9, '9'),
+  KEYCODE_ENTRY(VK_MULTIPLY, '*'),
+  KEYCODE_ENTRY(VK_ADD, '+'),
+  KEYCODE_ENTRY(VK_SEPARATOR, 0),
+  KEYCODE_ENTRY(VK_SUBTRACT, '-'),
+  KEYCODE_ENTRY(VK_DECIMAL, '.'),
+  KEYCODE_ENTRY(VK_DIVIDE, '/'),
+  KEYCODE_ENTRY(VK_F1, NSF1FunctionKey),
+  KEYCODE_ENTRY(VK_F2, NSF2FunctionKey),
+  KEYCODE_ENTRY(VK_F3, NSF3FunctionKey),
+  KEYCODE_ENTRY(VK_F4, NSF4FunctionKey),
+  KEYCODE_ENTRY(VK_F5, NSF5FunctionKey),
+  KEYCODE_ENTRY(VK_F6, NSF6FunctionKey),
+  KEYCODE_ENTRY(VK_F7, NSF7FunctionKey),
+  KEYCODE_ENTRY(VK_F8, NSF8FunctionKey),
+  KEYCODE_ENTRY(VK_F9, NSF9FunctionKey),
+  KEYCODE_ENTRY(VK_F10, NSF10FunctionKey),
+  KEYCODE_ENTRY(VK_F11, NSF11FunctionKey),
+  KEYCODE_ENTRY(VK_F12, NSF12FunctionKey),
+  KEYCODE_ENTRY(VK_F13, NSF13FunctionKey),
+  KEYCODE_ENTRY(VK_F14, NSF14FunctionKey),
+  KEYCODE_ENTRY(VK_F15, NSF15FunctionKey),
+  KEYCODE_ENTRY(VK_F16, NSF16FunctionKey),
+  KEYCODE_ENTRY(VK_F17, NSF17FunctionKey),
+  KEYCODE_ENTRY(VK_F18, NSF18FunctionKey),
+  KEYCODE_ENTRY(VK_F19, NSF19FunctionKey),
+  KEYCODE_ENTRY(VK_F20, NSF20FunctionKey),
+  KEYCODE_ENTRY(VK_F21, NSF21FunctionKey),
+  KEYCODE_ENTRY(VK_F22, NSF22FunctionKey),
+  KEYCODE_ENTRY(VK_F23, NSF23FunctionKey),
+  KEYCODE_ENTRY(VK_F24, NSF24FunctionKey),
+  KEYCODE_ENTRY(VK_NUM_LOCK, NSClearLineFunctionKey),
+  KEYCODE_ENTRY(VK_SCROLL_LOCK, NSScrollLockFunctionKey),
+  KEYCODE_ENTRY(VK_COMMA, ','),
+  KEYCODE_ENTRY(VK_PERIOD, '.'),
+  KEYCODE_ENTRY(VK_SLASH, '/'),
+  KEYCODE_ENTRY(VK_BACK_QUOTE, '`'),
+  KEYCODE_ENTRY(VK_OPEN_BRACKET, '['),
+  KEYCODE_ENTRY(VK_BACK_SLASH, '\\'),
+  KEYCODE_ENTRY(VK_CLOSE_BRACKET, ']'),
+  KEYCODE_ENTRY(VK_QUOTE, '\'')
+
+#undef KEYCODE_ENTRY
+
+};
+
+uint32_t
+nsCocoaUtils::ConvertGeckoNameToMacCharCode(const nsAString& aKeyCodeName)
+{
+  if (aKeyCodeName.IsEmpty()) {
+    return 0;
+  }
+
+  nsAutoCString keyCodeName;
+  keyCodeName.AssignWithConversion(aKeyCodeName);
+  // We want case-insensitive comparison with data stored as uppercase.
+  ToUpperCase(keyCodeName);
+
+  uint32_t keyCodeNameLength = keyCodeName.Length();
+  const char* keyCodeNameStr = keyCodeName.get();
+  for (uint16_t i = 0; i < ArrayLength(gKeyConversions); ++i) {
+    if (keyCodeNameLength == gKeyConversions[i].strLength &&
+        nsCRT::strcmp(gKeyConversions[i].str, keyCodeNameStr) == 0) {
+      return gKeyConversions[i].charCode;
+    }
+  }
+
+  return 0;
+}
+
+uint32_t
+nsCocoaUtils::ConvertGeckoKeyCodeToMacCharCode(uint32_t aKeyCode)
+{
+  if (!aKeyCode) {
+    return 0;
+  }
+
+  for (uint16_t i = 0; i < ArrayLength(gKeyConversions); ++i) {
+    if (gKeyConversions[i].geckoKeyCode == aKeyCode) {
+      return gKeyConversions[i].charCode;
+    }
+  }
+
+  return 0;
+}
+
+NSMutableAttributedString*
+nsCocoaUtils::GetNSMutableAttributedString(
+                const nsAString& aText,
+                const nsTArray<mozilla::FontRange>& aFontRanges,
+                const bool aIsVertical,
+                const CGFloat aBackingScaleFactor)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL
+
+  NSString* nsstr = nsCocoaUtils::ToNSString(aText);
+  NSMutableAttributedString* attrStr =
+    [[[NSMutableAttributedString alloc] initWithString:nsstr
+                                            attributes:nil] autorelease];
+
+  int32_t lastOffset = aText.Length();
+  for (auto i = aFontRanges.Length(); i > 0; --i) {
+    const FontRange& fontRange = aFontRanges[i - 1];
+    NSString* fontName = nsCocoaUtils::ToNSString(fontRange.mFontName);
+    CGFloat fontSize = fontRange.mFontSize / aBackingScaleFactor;
+    NSFont* font = [NSFont fontWithName:fontName size:fontSize];
+    if (!font) {
+      font = [NSFont systemFontOfSize:fontSize];
+    }
+
+    NSDictionary* attrs = @{ NSFontAttributeName: font };
+    NSRange range = NSMakeRange(fontRange.mStartOffset,
+                                lastOffset - fontRange.mStartOffset);
+    [attrStr setAttributes:attrs range:range];
+    lastOffset = fontRange.mStartOffset;
+  }
+
+  if (aIsVertical) {
+    [attrStr addAttribute:NSVerticalGlyphFormAttributeName
+                    value:[NSNumber numberWithInt: 1]
+                    range:NSMakeRange(0, [attrStr length])];
+  }
+
+  return attrStr;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL
+}
diff --git a/widget/cocoa/nsCocoaWindow.h b/widget/cocoa/nsCocoaWindow.h
new file mode 100644
index 0000000000..1913696b8c
--- /dev/null
+++ b/widget/cocoa/nsCocoaWindow.h
@@ -0,0 +1,426 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsCocoaWindow_h_
+#define nsCocoaWindow_h_
+
+#undef DARWIN
+
+#import <Cocoa/Cocoa.h>
+
+#include "mozilla/RefPtr.h"
+#include "nsBaseWidget.h"
+#include "nsPIWidgetCocoa.h"
+#include "nsCocoaUtils.h"
+
+class nsCocoaWindow;
+class nsChildView;
+class nsMenuBarX;
+@class ChildView;
+
+typedef struct _nsCocoaWindowList {
+  _nsCocoaWindowList() : prev(nullptr), window(nullptr) {}
+  struct _nsCocoaWindowList *prev;
+  nsCocoaWindow *window; // Weak
+} nsCocoaWindowList;
+
+// NSWindow subclass that is the base class for all of our own window classes.
+// Among other things, this class handles the storage of those settings that
+// need to be persisted across window destruction and reconstruction, i.e. when
+// switching to and from fullscreen mode.
+// We don't save shadow, transparency mode or background color because it's not
+// worth the hassle - Gecko will reset them anyway as soon as the window is
+// resized.
+@interface BaseWindow : NSWindow
+{
+  // Data Storage
+  NSMutableDictionary* mState;
+  BOOL mDrawsIntoWindowFrame;
+  NSColor* mActiveTitlebarColor;
+  NSColor* mInactiveTitlebarColor;
+
+  // Shadow
+  BOOL mScheduledShadowInvalidation;
+
+  // Invalidation disabling
+  BOOL mDisabledNeedsDisplay;
+
+  // DPI cache. Getting the physical screen size (CGDisplayScreenSize)
+  // is ridiculously slow, so we cache it in the toplevel window for all
+  // descendants to use.
+  float mDPI;
+
+  NSTrackingArea* mTrackingArea;
+
+  NSRect mDirtyRect;
+
+  BOOL mBeingShown;
+  BOOL mDrawTitle;
+  BOOL mBrightTitlebarForeground;
+  BOOL mUseMenuStyle;
+}
+
+- (void)importState:(NSDictionary*)aState;
+- (NSMutableDictionary*)exportState;
+- (void)setDrawsContentsIntoWindowFrame:(BOOL)aState;
+- (BOOL)drawsContentsIntoWindowFrame;
+- (void)setTitlebarColor:(NSColor*)aColor forActiveWindow:(BOOL)aActive;
+- (NSColor*)titlebarColorForActiveWindow:(BOOL)aActive;
+
+- (void)deferredInvalidateShadow;
+- (void)invalidateShadow;
+- (float)getDPI;
+
+- (void)mouseEntered:(NSEvent*)aEvent;
+- (void)mouseExited:(NSEvent*)aEvent;
+- (void)mouseMoved:(NSEvent*)aEvent;
+- (void)updateTrackingArea;
+- (NSView*)trackingAreaView;
+
+- (void)setBeingShown:(BOOL)aValue;
+- (BOOL)isBeingShown;
+- (BOOL)isVisibleOrBeingShown;
+
+- (ChildView*)mainChildView;
+
+- (NSArray*)titlebarControls;
+
+- (void)setWantsTitleDrawn:(BOOL)aDrawTitle;
+- (BOOL)wantsTitleDrawn;
+
+- (void)setUseBrightTitlebarForeground:(BOOL)aBrightForeground;
+- (BOOL)useBrightTitlebarForeground;
+
+- (void)disableSetNeedsDisplay;
+- (void)enableSetNeedsDisplay;
+
+- (NSRect)getAndResetNativeDirtyRect;
+
+- (void)setUseMenuStyle:(BOOL)aValue;
+
+@end
+
+@interface NSWindow (Undocumented)
+
+// If a window has been explicitly removed from the "window cache" (to
+// deactivate it), it's sometimes necessary to "reset" it to reactivate it
+// (and put it back in the "window cache").  One way to do this, which Apple
+// often uses, is to set the "window number" to '-1' and then back to its
+// original value.
+- (void)_setWindowNumber:(NSInteger)aNumber;
+
+// If we set the window's stylemask to be textured, the corners on the bottom of
+// the window are rounded by default. We use this private method to make
+// the corners square again, a la Safari. Starting with 10.7, all windows have
+// rounded bottom corners, so this call doesn't have any effect there.
+- (void)setBottomCornerRounded:(BOOL)rounded;
+- (BOOL)bottomCornerRounded;
+
+// Present in the same form on OS X since at least OS X 10.5.
+- (NSRect)contentRectForFrameRect:(NSRect)windowFrame styleMask:(NSUInteger)windowStyle;
+- (NSRect)frameRectForContentRect:(NSRect)windowContentRect styleMask:(NSUInteger)windowStyle;
+
+// Present since at least OS X 10.5.  The OS calls this method on NSWindow
+// (and its subclasses) to find out which NSFrameView subclass to instantiate
+// to create its "frame view".
++ (Class)frameViewClassForStyleMask:(NSUInteger)styleMask;
+
+@end
+
+@interface PopupWindow : BaseWindow
+{
+@private
+  BOOL mIsContextMenu;
+}
+
+- (id)initWithContentRect:(NSRect)contentRect styleMask:(NSUInteger)styleMask
+      backing:(NSBackingStoreType)bufferingType defer:(BOOL)deferCreation;
+- (BOOL)isContextMenu;
+- (void)setIsContextMenu:(BOOL)flag;
+- (BOOL)canBecomeMainWindow;
+
+@end
+
+@interface BorderlessWindow : BaseWindow
+{
+}
+
+- (BOOL)canBecomeKeyWindow;
+- (BOOL)canBecomeMainWindow;
+
+@end
+
+@interface WindowDelegate : NSObject <NSWindowDelegate>
+{
+  nsCocoaWindow* mGeckoWindow; // [WEAK] (we are owned by the window)
+  // Used to avoid duplication when we send NS_ACTIVATE and
+  // NS_DEACTIVATE to Gecko for toplevel widgets.  Starts out
+  // false.
+  bool mToplevelActiveState;
+  BOOL mHasEverBeenZoomed;
+}
++ (void)paintMenubarForWindow:(NSWindow*)aWindow;
+- (id)initWithGeckoWindow:(nsCocoaWindow*)geckoWind;
+- (void)windowDidResize:(NSNotification*)aNotification;
+- (nsCocoaWindow*)geckoWidget;
+- (bool)toplevelActiveState;
+- (void)sendToplevelActivateEvents;
+- (void)sendToplevelDeactivateEvents;
+@end
+
+@class ToolbarWindow;
+
+// NSColor subclass that allows us to draw separate colors both in the titlebar
+// and for background of the window.
+@interface TitlebarAndBackgroundColor : NSColor
+{
+  ToolbarWindow *mWindow; // [WEAK] (we are owned by the window)
+}
+
+- (id)initWithWindow:(ToolbarWindow*)aWindow;
+
+@end
+
+// NSWindow subclass for handling windows with toolbars.
+@interface ToolbarWindow : BaseWindow
+{
+  TitlebarAndBackgroundColor *mColor; // strong
+  CGFloat mUnifiedToolbarHeight;
+  NSColor *mBackgroundColor; // strong
+  NSView *mTitlebarView; // strong
+  NSRect mWindowButtonsRect;
+  NSRect mFullScreenButtonRect;
+}
+// Pass nil here to get the default appearance.
+- (void)setTitlebarColor:(NSColor*)aColor forActiveWindow:(BOOL)aActive;
+- (void)setUnifiedToolbarHeight:(CGFloat)aHeight;
+- (CGFloat)unifiedToolbarHeight;
+- (CGFloat)titlebarHeight;
+- (NSRect)titlebarRect;
+- (void)setTitlebarNeedsDisplayInRect:(NSRect)aRect sync:(BOOL)aSync;
+- (void)setTitlebarNeedsDisplayInRect:(NSRect)aRect;
+- (void)setDrawsContentsIntoWindowFrame:(BOOL)aState;
+- (void)setSheetAttachmentPosition:(CGFloat)aY;
+- (void)placeWindowButtons:(NSRect)aRect;
+- (void)placeFullScreenButton:(NSRect)aRect;
+- (NSPoint)windowButtonsPositionWithDefaultPosition:(NSPoint)aDefaultPosition;
+- (NSPoint)fullScreenButtonPositionWithDefaultPosition:(NSPoint)aDefaultPosition;
+- (void)setTemporaryBackgroundColor;
+- (void)restoreBackgroundColor;
+@end
+
+class nsCocoaWindow : public nsBaseWidget, public nsPIWidgetCocoa
+{
+private:
+  typedef nsBaseWidget Inherited;
+
+public:
+
+    nsCocoaWindow();
+
+    NS_DECL_ISUPPORTS_INHERITED
+    NS_DECL_NSPIWIDGETCOCOA
+
+    virtual MOZ_MUST_USE nsresult Create(nsIWidget* aParent,
+                                         nsNativeWidget aNativeParent,
+                                         const DesktopIntRect& aRect,
+                                         nsWidgetInitData* aInitData = nullptr)
+                                         override;
+
+    virtual MOZ_MUST_USE nsresult Create(nsIWidget* aParent,
+                                         nsNativeWidget aNativeParent,
+                                         const LayoutDeviceIntRect& aRect,
+                                         nsWidgetInitData* aInitData = nullptr)
+                                         override;
+
+    virtual void            Destroy() override;
+
+    NS_IMETHOD              Show(bool aState) override;
+    virtual nsIWidget*      GetSheetWindowParent(void) override;
+    NS_IMETHOD              Enable(bool aState) override;
+    virtual bool            IsEnabled() const override;
+    virtual void            SetModal(bool aState) override;
+    virtual void            SetFakeModal(bool aState) override;
+    virtual bool            IsRunningAppModal() override;
+    virtual bool            IsVisible() const override;
+    NS_IMETHOD              SetFocus(bool aState=false) override;
+    virtual LayoutDeviceIntPoint WidgetToScreenOffset() override;
+    virtual LayoutDeviceIntPoint GetClientOffset() override;
+    virtual LayoutDeviceIntSize
+    ClientToWindowSize(const LayoutDeviceIntSize& aClientSize) override;
+
+    virtual void* GetNativeData(uint32_t aDataType) override;
+
+    virtual void            ConstrainPosition(bool aAllowSlop,
+                                              int32_t *aX, int32_t *aY) override;
+    virtual void            SetSizeConstraints(const SizeConstraints& aConstraints) override;
+    NS_IMETHOD              Move(double aX, double aY) override;
+    virtual void            SetSizeMode(nsSizeMode aMode) override;
+    NS_IMETHOD              HideWindowChrome(bool aShouldHide) override;
+
+    void EnteredFullScreen(bool aFullScreen, bool aNativeMode = true);
+    virtual bool PrepareForFullscreenTransition(nsISupports** aData) override;
+    virtual void PerformFullscreenTransition(FullscreenTransitionStage aStage,
+                                             uint16_t aDuration,
+                                             nsISupports* aData,
+                                             nsIRunnable* aCallback) override;
+    virtual nsresult MakeFullScreen(
+      bool aFullScreen, nsIScreen* aTargetScreen = nullptr) override final;
+    NS_IMETHOD MakeFullScreenWithNativeTransition(
+      bool aFullScreen, nsIScreen* aTargetScreen = nullptr) override final;
+    NSAnimation* FullscreenTransitionAnimation() const { return mFullscreenTransitionAnimation; }
+    void ReleaseFullscreenTransitionAnimation()
+    {
+      MOZ_ASSERT(mFullscreenTransitionAnimation,
+                 "Should only be called when there is animation");
+      [mFullscreenTransitionAnimation release];
+      mFullscreenTransitionAnimation = nil;
+    }
+
+    NS_IMETHOD              Resize(double aWidth, double aHeight, bool aRepaint) override;
+    NS_IMETHOD              Resize(double aX, double aY, double aWidth, double aHeight, bool aRepaint) override;
+    virtual LayoutDeviceIntRect GetClientBounds() override;
+    virtual LayoutDeviceIntRect GetScreenBounds() override;
+    void                    ReportMoveEvent();
+    void                    ReportSizeEvent();
+    NS_IMETHOD              SetCursor(nsCursor aCursor) override;
+    NS_IMETHOD              SetCursor(imgIContainer* aCursor, uint32_t aHotspotX, uint32_t aHotspotY) override;
+
+    CGFloat                 BackingScaleFactor();
+    void                    BackingScaleFactorChanged();
+    virtual double          GetDefaultScaleInternal() override;
+    virtual int32_t         RoundsWidgetCoordinatesTo() override;
+
+    mozilla::DesktopToLayoutDeviceScale GetDesktopToDeviceScale() final {
+      return mozilla::DesktopToLayoutDeviceScale(BackingScaleFactor());
+    }
+
+    NS_IMETHOD              SetTitle(const nsAString& aTitle) override;
+
+    NS_IMETHOD Invalidate(const LayoutDeviceIntRect& aRect) override;
+    virtual nsresult ConfigureChildren(const nsTArray<Configuration>& aConfigurations) override;
+    virtual LayerManager* GetLayerManager(PLayerTransactionChild* aShadowManager = nullptr,
+                                          LayersBackend aBackendHint = mozilla::layers::LayersBackend::LAYERS_NONE,
+                                          LayerManagerPersistence aPersistence = LAYER_MANAGER_CURRENT) override;
+    NS_IMETHOD DispatchEvent(mozilla::WidgetGUIEvent* aEvent,
+                             nsEventStatus& aStatus) override;
+    virtual void CaptureRollupEvents(nsIRollupListener * aListener,
+                                     bool aDoCapture) override;
+    NS_IMETHOD GetAttention(int32_t aCycleCount) override;
+    virtual bool HasPendingInputEvent() override;
+    virtual nsTransparencyMode GetTransparencyMode() override;
+    virtual void SetTransparencyMode(nsTransparencyMode aMode) override;
+    virtual void SetWindowShadowStyle(int32_t aStyle) override;
+    virtual void SetShowsToolbarButton(bool aShow) override;
+    virtual void SetShowsFullScreenButton(bool aShow) override;
+    virtual void SetWindowAnimationType(WindowAnimationType aType) override;
+    virtual void SetDrawsTitle(bool aDrawTitle) override;
+    virtual void SetUseBrightTitlebarForeground(bool aBrightForeground) override;
+    NS_IMETHOD SetNonClientMargins(LayoutDeviceIntMargin& aMargins) override;
+    virtual void SetWindowTitlebarColor(nscolor aColor, bool aActive) override;
+    virtual void SetDrawsInTitlebar(bool aState) override;
+    virtual void UpdateThemeGeometries(const nsTArray<ThemeGeometry>& aThemeGeometries) override;
+    virtual nsresult SynthesizeNativeMouseEvent(LayoutDeviceIntPoint aPoint,
+                                                uint32_t aNativeMessage,
+                                                uint32_t aModifierFlags,
+                                                nsIObserver* aObserver) override;
+
+    void DispatchSizeModeEvent();
+
+    // be notified that a some form of drag event needs to go into Gecko
+    virtual bool DragEvent(unsigned int aMessage, mozilla::gfx::Point aMouseGlobal, UInt16 aKeyModifiers);
+
+    bool HasModalDescendents() { return mNumModalDescendents > 0; }
+    NSWindow *GetCocoaWindow() { return mWindow; }
+
+    void SetMenuBar(nsMenuBarX* aMenuBar);
+    nsMenuBarX *GetMenuBar();
+
+    NS_IMETHOD_(void) SetInputContext(
+                        const InputContext& aContext,
+                        const InputContextAction& aAction) override;
+    NS_IMETHOD_(InputContext) GetInputContext() override
+    {
+      return mInputContext;
+    }
+    NS_IMETHOD_(bool) ExecuteNativeKeyBinding(
+                        NativeKeyBindingsType aType,
+                        const mozilla::WidgetKeyboardEvent& aEvent,
+                        DoCommandCallback aCallback,
+                        void* aCallbackData) override;
+
+    void SetPopupWindowLevel();
+
+protected:
+  virtual ~nsCocoaWindow();
+
+  nsresult             CreateNativeWindow(const NSRect &aRect,
+                                          nsBorderStyle aBorderStyle,
+                                          bool aRectIsFrameRect);
+  nsresult             CreatePopupContentView(const LayoutDeviceIntRect &aRect,
+                                              nsWidgetInitData* aInitData);
+  void                 DestroyNativeWindow();
+  void                 AdjustWindowShadow();
+  void                 SetWindowBackgroundBlur();
+  void                 UpdateBounds();
+
+  nsresult             DoResize(double aX, double aY, double aWidth, double aHeight,
+                                bool aRepaint, bool aConstrainToCurrentScreen);
+
+  inline bool ShouldToggleNativeFullscreen(bool aFullScreen,
+                                           bool aUseSystemTransition);
+  nsresult DoMakeFullScreen(bool aFullScreen, bool aUseSystemTransition);
+
+  virtual already_AddRefed<nsIWidget>
+  AllocateChildPopupWidget() override
+  {
+    static NS_DEFINE_IID(kCPopUpCID, NS_POPUP_CID);
+    nsCOMPtr<nsIWidget> widget = do_CreateInstance(kCPopUpCID);
+    return widget.forget();
+  }
+
+  nsIWidget*           mParent;         // if we're a popup, this is our parent [WEAK]
+  nsIWidget*           mAncestorLink;   // link to traverse ancestors [WEAK]
+  BaseWindow*          mWindow;         // our cocoa window [STRONG]
+  WindowDelegate*      mDelegate;       // our delegate for processing window msgs [STRONG]
+  RefPtr<nsMenuBarX> mMenuBar;
+  NSWindow*            mSheetWindowParent; // if this is a sheet, this is the NSWindow it's attached to
+  nsChildView*         mPopupContentView; // if this is a popup, this is its content widget
+  // if this is a toplevel window, and there is any ongoing fullscreen
+  // transition, it is the animation object.
+  NSAnimation*         mFullscreenTransitionAnimation;
+  int32_t              mShadowStyle;
+
+  CGFloat              mBackingScaleFactor;
+
+  WindowAnimationType  mAnimationType;
+
+  bool                 mWindowMadeHere; // true if we created the window, false for embedding
+  bool                 mSheetNeedsShow; // if this is a sheet, are we waiting to be shown?
+                                        // this is used for sibling sheet contention only
+  bool                 mInFullScreenMode;
+  bool                 mInFullScreenTransition; // true from the request to enter/exit fullscreen
+                                                // (MakeFullScreen() call) to EnteredFullScreen()
+  bool                 mModal;
+  bool                 mFakeModal;
+
+  // Only true on 10.7+ if SetShowsFullScreenButton(true) is called.
+  bool                 mSupportsNativeFullScreen;
+  // Whether we are currently using native fullscreen. It could be false because
+  // we are in the DOM fullscreen where we do not use the native fullscreen.
+  bool                 mInNativeFullScreenMode;
+
+  bool                 mIsAnimationSuppressed;
+
+  bool                 mInReportMoveEvent; // true if in a call to ReportMoveEvent().
+  bool                 mInResize; // true if in a call to DoResize().
+
+  bool                 mAlwaysOnTop;
+
+  int32_t              mNumModalDescendents;
+  InputContext         mInputContext;
+};
+
+#endif // nsCocoaWindow_h_
diff --git a/widget/cocoa/nsCocoaWindow.mm b/widget/cocoa/nsCocoaWindow.mm
new file mode 100644
index 0000000000..a437504fd1
--- /dev/null
+++ b/widget/cocoa/nsCocoaWindow.mm
@@ -0,0 +1,3881 @@
+/* -*- Mode: Objective-C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsCocoaWindow.h"
+
+#include "NativeKeyBindings.h"
+#include "TextInputHandler.h"
+#include "nsObjCExceptions.h"
+#include "nsCOMPtr.h"
+#include "nsWidgetsCID.h"
+#include "nsIRollupListener.h"
+#include "nsChildView.h"
+#include "nsWindowMap.h"
+#include "nsAppShell.h"
+#include "nsIAppShellService.h"
+#include "nsIBaseWindow.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIXULWindow.h"
+#include "nsToolkit.h"
+#include "nsIDOMWindow.h"
+#include "nsPIDOMWindow.h"
+#include "nsIDOMElement.h"
+#include "nsThreadUtils.h"
+#include "nsMenuBarX.h"
+#include "nsMenuUtilsX.h"
+#include "nsStyleConsts.h"
+#include "nsNativeThemeColors.h"
+#include "nsNativeThemeCocoa.h"
+#include "nsChildView.h"
+#include "nsCocoaFeatures.h"
+#include "nsIScreenManager.h"
+#include "nsIWidgetListener.h"
+#include "nsIPresShell.h"
+#include "nsScreenCocoa.h"
+#include "VibrancyManager.h"
+
+#include "gfxPlatform.h"
+#include "qcms.h"
+
+#include "mozilla/AutoRestore.h"
+#include "mozilla/BasicEvents.h"
+#include "mozilla/Preferences.h"
+#include <algorithm>
+
+namespace mozilla {
+namespace layers {
+class LayerManager;
+} // namespace layers
+} // namespace mozilla
+using namespace mozilla::layers;
+using namespace mozilla::widget;
+using namespace mozilla;
+
+int32_t gXULModalLevel = 0;
+
+// In principle there should be only one app-modal window at any given time.
+// But sometimes, despite our best efforts, another window appears above the
+// current app-modal window.  So we need to keep a linked list of app-modal
+// windows.  (A non-sheet window that appears above an app-modal window is
+// also made app-modal.)  See nsCocoaWindow::SetModal().
+nsCocoaWindowList *gGeckoAppModalWindowList = NULL;
+
+// defined in nsMenuBarX.mm
+extern NSMenu* sApplicationMenu; // Application menu shared by all menubars
+
+// defined in nsChildView.mm
+extern BOOL                gSomeMenuBarPainted;
+
+#if !defined(MAC_OS_X_VERSION_10_12) || \
+    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_12
+
+@interface NSWindow(AutomaticWindowTabbing)
++ (void)setAllowsAutomaticWindowTabbing:(BOOL)allow;
+@end
+
+#endif
+
+extern "C" {
+  // CGSPrivate.h
+  typedef NSInteger CGSConnection;
+  typedef NSInteger CGSWindow;
+  typedef NSUInteger CGSWindowFilterRef;
+  extern CGSConnection _CGSDefaultConnection(void);
+  extern CGError CGSSetWindowShadowAndRimParameters(const CGSConnection cid, CGSWindow wid, float standardDeviation, float density, int offsetX, int offsetY, unsigned int flags);
+  extern CGError CGSSetWindowBackgroundBlurRadius(CGSConnection cid, CGSWindow wid, NSUInteger blur);
+}
+
+#define NS_APPSHELLSERVICE_CONTRACTID "@mozilla.org/appshell/appShellService;1"
+
+NS_IMPL_ISUPPORTS_INHERITED(nsCocoaWindow, Inherited, nsPIWidgetCocoa)
+
+// A note on testing to see if your object is a sheet...
+// |mWindowType == eWindowType_sheet| is true if your gecko nsIWidget is a sheet
+// widget - whether or not the sheet is showing. |[mWindow isSheet]| will return
+// true *only when the sheet is actually showing*. Choose your test wisely.
+
+static void RollUpPopups()
+{
+  nsIRollupListener* rollupListener = nsBaseWidget::GetActiveRollupListener();
+  NS_ENSURE_TRUE_VOID(rollupListener);
+  nsCOMPtr<nsIWidget> rollupWidget = rollupListener->GetRollupWidget();
+  if (!rollupWidget)
+    return;
+  rollupListener->Rollup(0, true, nullptr, nullptr);
+}
+
+nsCocoaWindow::nsCocoaWindow()
+: mParent(nullptr)
+, mAncestorLink(nullptr)
+, mWindow(nil)
+, mDelegate(nil)
+, mSheetWindowParent(nil)
+, mPopupContentView(nil)
+, mFullscreenTransitionAnimation(nil)
+, mShadowStyle(NS_STYLE_WINDOW_SHADOW_DEFAULT)
+, mBackingScaleFactor(0.0)
+, mAnimationType(nsIWidget::eGenericWindowAnimation)
+, mWindowMadeHere(false)
+, mSheetNeedsShow(false)
+, mInFullScreenMode(false)
+, mInFullScreenTransition(false)
+, mModal(false)
+, mFakeModal(false)
+, mSupportsNativeFullScreen(false)
+, mInNativeFullScreenMode(false)
+, mIsAnimationSuppressed(false)
+, mInReportMoveEvent(false)
+, mInResize(false)
+, mAlwaysOnTop(false)
+, mNumModalDescendents(0)
+{
+  if ([NSWindow respondsToSelector:@selector(setAllowsAutomaticWindowTabbing:)]) {
+    // Disable automatic tabbing on 10.12. We need to do this before we
+    // orderFront any of our windows.
+    [NSWindow setAllowsAutomaticWindowTabbing:NO];
+  }
+}
+
+void nsCocoaWindow::DestroyNativeWindow()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow)
+    return;
+
+  // We want to unhook the delegate here because we don't want events
+  // sent to it after this object has been destroyed.
+  [mWindow setDelegate:nil];
+  [mWindow close];
+  mWindow = nil;
+  [mDelegate autorelease];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsCocoaWindow::~nsCocoaWindow()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Notify the children that we're gone.  Popup windows (e.g. tooltips) can
+  // have nsChildView children.  'kid' is an nsChildView object if and only if
+  // its 'type' is 'eWindowType_child'.
+  // childView->ResetParent() can change our list of children while it's
+  // being iterated, so the way we iterate the list must allow for this.
+  for (nsIWidget* kid = mLastChild; kid;) {
+    nsWindowType kidType = kid->WindowType();
+    if (kidType == eWindowType_child) {
+      nsChildView* childView = static_cast<nsChildView*>(kid);
+      kid = kid->GetPrevSibling();
+      childView->ResetParent();
+    } else {
+      nsCocoaWindow* childWindow = static_cast<nsCocoaWindow*>(kid);
+      childWindow->mParent = nullptr;
+      childWindow->mAncestorLink = mAncestorLink;
+      kid = kid->GetPrevSibling();
+    }
+  }
+
+  if (mWindow && mWindowMadeHere) {
+    DestroyNativeWindow();
+  }
+
+  NS_IF_RELEASE(mPopupContentView);
+
+  // Deal with the possiblity that we're being destroyed while running modal.
+  if (mModal) {
+    NS_WARNING("Widget destroyed while running modal!");
+    --gXULModalLevel;
+    NS_ASSERTION(gXULModalLevel >= 0, "Weirdness setting modality!");
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Find the screen that overlaps aRect the most,
+// if none are found default to the mainScreen.
+static NSScreen*
+FindTargetScreenForRect(const DesktopIntRect& aRect)
+{
+  NSScreen *targetScreen = [NSScreen mainScreen];
+  NSEnumerator *screenEnum = [[NSScreen screens] objectEnumerator];
+  int largestIntersectArea = 0;
+  while (NSScreen *screen = [screenEnum nextObject]) {
+    DesktopIntRect screenRect =
+      nsCocoaUtils::CocoaRectToGeckoRect([screen visibleFrame]);
+    screenRect = screenRect.Intersect(aRect);
+    int area = screenRect.width * screenRect.height;
+    if (area > largestIntersectArea) {
+      largestIntersectArea = area;
+      targetScreen = screen;
+    }
+  }
+  return targetScreen;
+}
+
+// fits the rect to the screen that contains the largest area of it,
+// or to aScreen if a screen is passed in
+// NB: this operates with aRect in desktop pixels
+static void
+FitRectToVisibleAreaForScreen(DesktopIntRect& aRect, NSScreen* aScreen)
+{
+  if (!aScreen) {
+    aScreen = FindTargetScreenForRect(aRect);
+  }
+
+  DesktopIntRect screenBounds =
+    nsCocoaUtils::CocoaRectToGeckoRect([aScreen visibleFrame]);
+
+  if (aRect.width > screenBounds.width) {
+    aRect.width = screenBounds.width;
+  }
+  if (aRect.height > screenBounds.height) {
+    aRect.height = screenBounds.height;
+  }
+  
+  if (aRect.x - screenBounds.x + aRect.width > screenBounds.width) {
+    aRect.x += screenBounds.width - (aRect.x - screenBounds.x + aRect.width);
+  }
+  if (aRect.y - screenBounds.y + aRect.height > screenBounds.height) {
+    aRect.y += screenBounds.height - (aRect.y - screenBounds.y + aRect.height);
+  }
+
+  // If the left/top edge of the window is off the screen in either direction,
+  // then set the window to start at the left/top edge of the screen.
+  if (aRect.x < screenBounds.x || aRect.x > (screenBounds.x + screenBounds.width)) {
+    aRect.x = screenBounds.x;
+  }
+  if (aRect.y < screenBounds.y || aRect.y > (screenBounds.y + screenBounds.height)) {
+    aRect.y = screenBounds.y;
+  }
+}
+
+// Some applications use native popup windows
+// (native context menus, native tooltips)
+static bool UseNativePopupWindows()
+{
+#ifdef MOZ_USE_NATIVE_POPUP_WINDOWS
+  return true;
+#else
+  return false;
+#endif /* MOZ_USE_NATIVE_POPUP_WINDOWS */
+}
+
+// aRect here is specified in desktop pixels
+nsresult
+nsCocoaWindow::Create(nsIWidget* aParent,
+                      nsNativeWidget aNativeParent,
+                      const DesktopIntRect& aRect,
+                      nsWidgetInitData* aInitData)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // Because the hidden window is created outside of an event loop,
+  // we have to provide an autorelease pool (see bug 559075).
+  nsAutoreleasePool localPool;
+
+  DesktopIntRect newBounds = aRect;
+  FitRectToVisibleAreaForScreen(newBounds, nullptr);
+
+  // Set defaults which can be overriden from aInitData in BaseCreate
+  mWindowType = eWindowType_toplevel;
+  mBorderStyle = eBorderStyle_default;
+
+  // Ensure that the toolkit is created.
+  nsToolkit::GetToolkit();
+
+  Inherited::BaseCreate(aParent, aInitData);
+
+  mParent = aParent;
+  mAncestorLink = aParent;
+
+  // Applications that use native popups don't want us to create popup windows.
+  if ((mWindowType == eWindowType_popup) && UseNativePopupWindows())
+    return NS_OK;
+
+  nsresult rv =
+    CreateNativeWindow(nsCocoaUtils::GeckoRectToCocoaRect(newBounds),
+                       mBorderStyle, false);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (mWindowType == eWindowType_popup) {
+    if (aInitData->mMouseTransparent) {
+      [mWindow setIgnoresMouseEvents:YES];
+    } else {
+      [mWindow setIgnoresMouseEvents:NO];
+    }
+    // now we can convert newBounds to device pixels for the window we created,
+    // as the child view expects a rect expressed in the dev pix of its parent
+    LayoutDeviceIntRect devRect =
+      RoundedToInt(newBounds * GetDesktopToDeviceScale());
+    return CreatePopupContentView(devRect, aInitData);
+  }
+
+  mIsAnimationSuppressed = aInitData->mIsAnimationSuppressed;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult
+nsCocoaWindow::Create(nsIWidget* aParent,
+                      nsNativeWidget aNativeParent,
+                      const LayoutDeviceIntRect& aRect,
+                      nsWidgetInitData* aInitData)
+{
+  DesktopIntRect desktopRect =
+    RoundedToInt(aRect / GetDesktopToDeviceScale());
+  return Create(aParent, aNativeParent, desktopRect, aInitData);
+}
+
+static unsigned int WindowMaskForBorderStyle(nsBorderStyle aBorderStyle)
+{
+  bool allOrDefault = (aBorderStyle == eBorderStyle_all ||
+                         aBorderStyle == eBorderStyle_default);
+
+  /* Apple's docs on NSWindow styles say that "a window's style mask should
+   * include NSTitledWindowMask if it includes any of the others [besides
+   * NSBorderlessWindowMask]".  This implies that a borderless window
+   * shouldn't have any other styles than NSBorderlessWindowMask.
+   */
+  if (!allOrDefault && !(aBorderStyle & eBorderStyle_title))
+    return NSBorderlessWindowMask;
+
+  unsigned int mask = NSTitledWindowMask;
+  if (allOrDefault || aBorderStyle & eBorderStyle_close)
+    mask |= NSClosableWindowMask;
+  if (allOrDefault || aBorderStyle & eBorderStyle_minimize)
+    mask |= NSMiniaturizableWindowMask;
+  if (allOrDefault || aBorderStyle & eBorderStyle_resizeh)
+    mask |= NSResizableWindowMask;
+
+  return mask;
+}
+
+// If aRectIsFrameRect, aRect specifies the frame rect of the new window.
+// Otherwise, aRect.x/y specify the position of the window's frame relative to
+// the bottom of the menubar and aRect.width/height specify the size of the
+// content rect.
+nsresult nsCocoaWindow::CreateNativeWindow(const NSRect &aRect,
+                                           nsBorderStyle aBorderStyle,
+                                           bool aRectIsFrameRect)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // We default to NSBorderlessWindowMask, add features if needed.
+  unsigned int features = NSBorderlessWindowMask;
+
+  // Configure the window we will create based on the window type.
+  switch (mWindowType)
+  {
+    case eWindowType_invisible:
+    case eWindowType_child:
+    case eWindowType_plugin:
+      break;
+    case eWindowType_popup:
+      if (aBorderStyle != eBorderStyle_default && mBorderStyle & eBorderStyle_title) {
+        features |= NSTitledWindowMask;
+        if (aBorderStyle & eBorderStyle_close) {
+          features |= NSClosableWindowMask;
+        }
+      }
+      break;
+    case eWindowType_toplevel:
+    case eWindowType_dialog:
+      features = WindowMaskForBorderStyle(aBorderStyle);
+      break;
+    case eWindowType_sheet:
+      if (mParent->WindowType() != eWindowType_invisible &&
+          aBorderStyle & eBorderStyle_resizeh) {
+        features = NSResizableWindowMask;
+      }
+      else {
+        features = NSMiniaturizableWindowMask;
+      }
+      features |= NSTitledWindowMask;
+      break;
+    default:
+      NS_ERROR("Unhandled window type!");
+      return NS_ERROR_FAILURE;
+  }
+
+  NSRect contentRect;
+
+  if (aRectIsFrameRect) {
+    contentRect = [NSWindow contentRectForFrameRect:aRect styleMask:features];
+  } else {
+    /* 
+     * We pass a content area rect to initialize the native Cocoa window. The
+     * content rect we give is the same size as the size we're given by gecko.
+     * The origin we're given for non-popup windows is moved down by the height
+     * of the menu bar so that an origin of (0,100) from gecko puts the window
+     * 100 pixels below the top of the available desktop area. We also move the
+     * origin down by the height of a title bar if it exists. This is so the
+     * origin that gecko gives us for the top-left of  the window turns out to
+     * be the top-left of the window we create. This is how it was done in
+     * Carbon. If it ought to be different we'll probably need to look at all
+     * the callers.
+     *
+     * Note: This means that if you put a secondary screen on top of your main
+     * screen and open a window in the top screen, it'll be incorrectly shifted
+     * down by the height of the menu bar. Same thing would happen in Carbon.
+     *
+     * Note: If you pass a rect with 0,0 for an origin, the window ends up in a
+     * weird place for some reason. This stops that without breaking popups.
+     */
+    // Compensate for difference between frame and content area height (e.g. title bar).
+    NSRect newWindowFrame = [NSWindow frameRectForContentRect:aRect styleMask:features];
+
+    contentRect = aRect;
+    contentRect.origin.y -= (newWindowFrame.size.height - aRect.size.height);
+
+    if (mWindowType != eWindowType_popup)
+      contentRect.origin.y -= [[NSApp mainMenu] menuBarHeight];
+  }
+
+  // NSLog(@"Top-level window being created at Cocoa rect: %f, %f, %f, %f\n",
+  //       rect.origin.x, rect.origin.y, rect.size.width, rect.size.height);
+
+  Class windowClass = [BaseWindow class];
+  // If we have a titlebar on a top-level window, we want to be able to control the 
+  // titlebar color (for unified windows), so use the special ToolbarWindow class. 
+  // Note that we need to check the window type because we mark sheets as 
+  // having titlebars.
+  if ((mWindowType == eWindowType_toplevel || mWindowType == eWindowType_dialog) &&
+      (features & NSTitledWindowMask))
+    windowClass = [ToolbarWindow class];
+  // If we're a popup window we need to use the PopupWindow class.
+  else if (mWindowType == eWindowType_popup)
+    windowClass = [PopupWindow class];
+  // If we're a non-popup borderless window we need to use the
+  // BorderlessWindow class.
+  else if (features == NSBorderlessWindowMask)
+    windowClass = [BorderlessWindow class];
+
+  // Create the window
+  mWindow = [[windowClass alloc] initWithContentRect:contentRect styleMask:features 
+                                 backing:NSBackingStoreBuffered defer:YES];
+
+  // Make sure that window titles don't leak to disk in private browsing mode
+  // due to macOS' resume feature.
+  [mWindow setRestorable:NO];
+  [mWindow disableSnapshotRestoration];
+
+  // setup our notification delegate. Note that setDelegate: does NOT retain.
+  mDelegate = [[WindowDelegate alloc] initWithGeckoWindow:this];
+  [mWindow setDelegate:mDelegate];
+
+  // Make sure that the content rect we gave has been honored.
+  NSRect wantedFrame = [mWindow frameRectForContentRect:contentRect];
+  if (!NSEqualRects([mWindow frame], wantedFrame)) {
+    // This can happen when the window is not on the primary screen.
+    [mWindow setFrame:wantedFrame display:NO];
+  }
+  UpdateBounds();
+
+  if (mWindowType == eWindowType_invisible) {
+    [mWindow setLevel:kCGDesktopWindowLevelKey];
+  }
+
+  if (mWindowType == eWindowType_popup) {
+    SetPopupWindowLevel();
+    [mWindow setBackgroundColor:[NSColor clearColor]];
+    [mWindow setOpaque:NO];
+  } else {
+    // Make sure that regular windows are opaque from the start, so that
+    // nsChildView::WidgetTypeSupportsAcceleration returns true for them.
+    [mWindow setOpaque:YES];
+  }
+
+  NSWindowCollectionBehavior newBehavior = [mWindow collectionBehavior];
+  if (mAlwaysOnTop) {
+    [mWindow setLevel:NSFloatingWindowLevel];
+    newBehavior |= NSWindowCollectionBehaviorCanJoinAllSpaces;
+  }
+  [mWindow setCollectionBehavior:newBehavior];
+
+  [mWindow setContentMinSize:NSMakeSize(60, 60)];
+  [mWindow disableCursorRects];
+
+  // Make sure the window starts out not draggable by the background.
+  // We will turn it on as necessary.
+  [mWindow setMovableByWindowBackground:NO];
+
+  [[WindowDataMap sharedWindowDataMap] ensureDataForWindow:mWindow];
+  mWindowMadeHere = true;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsCocoaWindow::CreatePopupContentView(const LayoutDeviceIntRect &aRect,
+	                                  nsWidgetInitData* aInitData)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // We need to make our content view a ChildView.
+  mPopupContentView = new nsChildView();
+  if (!mPopupContentView)
+    return NS_ERROR_FAILURE;
+
+  NS_ADDREF(mPopupContentView);
+
+  nsIWidget* thisAsWidget = static_cast<nsIWidget*>(this);
+  nsresult rv = mPopupContentView->Create(thisAsWidget, nullptr, aRect,
+                                          aInitData);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  NSView* contentView = [mWindow contentView];
+  ChildView* childView = (ChildView*)mPopupContentView->GetNativeData(NS_NATIVE_WIDGET);
+  [childView setFrame:NSZeroRect];
+  [childView setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
+  [contentView addSubview:childView];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void nsCocoaWindow::Destroy()
+{
+  if (mOnDestroyCalled)
+    return;
+  mOnDestroyCalled = true;
+
+  // SetFakeModal(true) is called for non-modal window opened by modal window.
+  // On Cocoa, it needs corresponding SetFakeModal(false) on destroy to restore
+  // ancestor windows' state.
+  if (mFakeModal) {
+    SetFakeModal(false);
+  }
+
+  // If we don't hide here we run into problems with panels, this is not ideal.
+  // (Bug 891424)
+  Show(false);
+
+  if (mPopupContentView)
+    mPopupContentView->Destroy();
+
+  if (mFullscreenTransitionAnimation) {
+    [mFullscreenTransitionAnimation stopAnimation];
+    ReleaseFullscreenTransitionAnimation();
+  }
+
+  nsBaseWidget::Destroy();
+  // nsBaseWidget::Destroy() calls GetParent()->RemoveChild(this). But we
+  // don't implement GetParent(), so we need to do the equivalent here.
+  if (mParent) {
+    mParent->RemoveChild(this);
+  }
+  nsBaseWidget::OnDestroy();
+
+  if (mInFullScreenMode) {
+    // On Lion we don't have to mess with the OS chrome when in Full Screen
+    // mode.  But we do have to destroy the native window here (and not wait
+    // for that to happen in our destructor).  We don't switch away from the
+    // native window's space until the window is destroyed, and otherwise this
+    // might not happen for several seconds (because at least one object
+    // holding a reference to ourselves is usually waiting to be garbage-
+    // collected).  See bug 757618.
+    if (mInNativeFullScreenMode) {
+      DestroyNativeWindow();
+    } else if (mWindow) {
+      nsCocoaUtils::HideOSChromeOnScreen(false);
+    }
+  }
+}
+
+nsIWidget* nsCocoaWindow::GetSheetWindowParent(void)
+{
+  if (mWindowType != eWindowType_sheet)
+    return nullptr;
+  nsCocoaWindow *parent = static_cast<nsCocoaWindow*>(mParent);
+  while (parent && (parent->mWindowType == eWindowType_sheet))
+    parent = static_cast<nsCocoaWindow*>(parent->mParent);
+  return parent;
+}
+
+void* nsCocoaWindow::GetNativeData(uint32_t aDataType)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSNULL;
+
+  void* retVal = nullptr;
+  
+  switch (aDataType) {
+    // to emulate how windows works, we always have to return a NSView
+    // for NS_NATIVE_WIDGET
+    case NS_NATIVE_WIDGET:
+    case NS_NATIVE_DISPLAY:
+      retVal = [mWindow contentView];
+      break;
+      
+    case NS_NATIVE_WINDOW:
+      retVal = mWindow;
+      break;
+      
+    case NS_NATIVE_GRAPHIC:
+      // There isn't anything that makes sense to return here,
+      // and it doesn't matter so just return nullptr.
+      NS_ERROR("Requesting NS_NATIVE_GRAPHIC on a top-level window!");
+      break;
+    case NS_RAW_NATIVE_IME_CONTEXT: {
+      retVal = GetPseudoIMEContext();
+      if (retVal) {
+        break;
+      }
+      NSView* view = mWindow ? [mWindow contentView] : nil;
+      if (view) {
+        retVal = [view inputContext];
+      }
+      // If inputContext isn't available on this window, return this window's
+      // pointer instead of nullptr since if this returns nullptr,
+      // IMEStateManager cannot manage composition with TextComposition
+      // instance.  Although, this case shouldn't occur.
+      if (NS_WARN_IF(!retVal)) {
+        retVal = this;
+      }
+      break;
+    }
+  }
+
+  return retVal;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSNULL;
+}
+
+bool nsCocoaWindow::IsVisible() const
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return (mWindow && ([mWindow isVisibleOrBeingShown] || mSheetNeedsShow));
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+void
+nsCocoaWindow::SetModal(bool aState)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow)
+    return;
+
+  // This is used during startup (outside the event loop) when creating
+  // the add-ons compatibility checking dialog and the profile manager UI;
+  // therefore, it needs to provide an autorelease pool to avoid cocoa
+  // objects leaking.
+  nsAutoreleasePool localPool;
+
+  mModal = aState;
+  nsCocoaWindow *ancestor = static_cast<nsCocoaWindow*>(mAncestorLink);
+  if (aState) {
+    ++gXULModalLevel;
+    // When a non-sheet window gets "set modal", make the window(s) that it
+    // appears over behave as they should.  We can't rely on native methods to
+    // do this, for the following reason:  The OS runs modal non-sheet windows
+    // in an event loop (using [NSApplication runModalForWindow:] or similar
+    // methods) that's incompatible with the modal event loop in nsXULWindow::
+    // ShowModal() (each of these event loops is "exclusive", and can't run at
+    // the same time as other (similar) event loops).
+    if (mWindowType != eWindowType_sheet) {
+      while (ancestor) {
+        if (ancestor->mNumModalDescendents++ == 0) {
+          NSWindow *aWindow = ancestor->GetCocoaWindow();
+          if (ancestor->mWindowType != eWindowType_invisible) {
+            [[aWindow standardWindowButton:NSWindowCloseButton] setEnabled:NO];
+            [[aWindow standardWindowButton:NSWindowMiniaturizeButton] setEnabled:NO];
+            [[aWindow standardWindowButton:NSWindowZoomButton] setEnabled:NO];
+          }
+        }
+        ancestor = static_cast<nsCocoaWindow*>(ancestor->mParent);
+      }
+      [mWindow setLevel:NSModalPanelWindowLevel];
+      nsCocoaWindowList *windowList = new nsCocoaWindowList;
+      if (windowList) {
+        windowList->window = this; // Don't ADDREF
+        windowList->prev = gGeckoAppModalWindowList;
+        gGeckoAppModalWindowList = windowList;
+      }
+    }
+  }
+  else {
+    --gXULModalLevel;
+    NS_ASSERTION(gXULModalLevel >= 0, "Mismatched call to nsCocoaWindow::SetModal(false)!");
+    if (mWindowType != eWindowType_sheet) {
+      while (ancestor) {
+        if (--ancestor->mNumModalDescendents == 0) {
+          NSWindow *aWindow = ancestor->GetCocoaWindow();
+          if (ancestor->mWindowType != eWindowType_invisible) {
+            [[aWindow standardWindowButton:NSWindowCloseButton] setEnabled:YES];
+            [[aWindow standardWindowButton:NSWindowMiniaturizeButton] setEnabled:YES];
+            [[aWindow standardWindowButton:NSWindowZoomButton] setEnabled:YES];
+          }
+        }
+        NS_ASSERTION(ancestor->mNumModalDescendents >= 0, "Widget hierarchy changed while modal!");
+        ancestor = static_cast<nsCocoaWindow*>(ancestor->mParent);
+      }
+      if (gGeckoAppModalWindowList) {
+        NS_ASSERTION(gGeckoAppModalWindowList->window == this, "Widget hierarchy changed while modal!");
+        nsCocoaWindowList *saved = gGeckoAppModalWindowList;
+        gGeckoAppModalWindowList = gGeckoAppModalWindowList->prev;
+        delete saved; // "window" not ADDREFed
+      }
+      if (mWindowType == eWindowType_popup)
+        SetPopupWindowLevel();
+      else
+        [mWindow setLevel:NSNormalWindowLevel];
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsCocoaWindow::SetFakeModal(bool aState)
+{
+    mFakeModal = aState;
+    SetModal(aState);
+}
+
+bool
+nsCocoaWindow::IsRunningAppModal()
+{
+  return [NSApp _isRunningAppModal];
+}
+
+// Hide or show this window
+NS_IMETHODIMP nsCocoaWindow::Show(bool bState)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!mWindow)
+    return NS_OK;
+
+  // We need to re-execute sometimes in order to bring already-visible
+  // windows forward.
+  if (!mSheetNeedsShow && !bState && ![mWindow isVisible])
+    return NS_OK;
+
+  // Protect against re-entering.
+  if (bState && [mWindow isBeingShown])
+    return NS_OK;
+
+  [mWindow setBeingShown:bState];
+
+  nsIWidget* parentWidget = mParent;
+  nsCOMPtr<nsPIWidgetCocoa> piParentWidget(do_QueryInterface(parentWidget));
+  NSWindow* nativeParentWindow = (parentWidget) ?
+    (NSWindow*)parentWidget->GetNativeData(NS_NATIVE_WINDOW) : nil;
+
+  if (bState && !mBounds.IsEmpty()) {
+    // Don't try to show a popup when the parent isn't visible or is minimized.
+    if (mWindowType == eWindowType_popup && nativeParentWindow) {
+      if (![nativeParentWindow isVisible] || [nativeParentWindow isMiniaturized]) {
+        return NS_ERROR_FAILURE;
+      }
+    }
+
+    if (mPopupContentView) {
+      // Ensure our content view is visible. We never need to hide it.
+      mPopupContentView->Show(true);
+    }
+
+    if (mWindowType == eWindowType_sheet) {
+      // bail if no parent window (its basically what we do in Carbon)
+      if (!nativeParentWindow || !piParentWidget)
+        return NS_ERROR_FAILURE;
+
+      NSWindow* topNonSheetWindow = nativeParentWindow;
+      
+      // If this sheet is the child of another sheet, hide the parent so that
+      // this sheet can be displayed. Leave the parent mSheetNeedsShow alone,
+      // that is only used to handle sibling sheet contention. The parent will
+      // return once there are no more child sheets.
+      bool parentIsSheet = false;
+      if (NS_SUCCEEDED(piParentWidget->GetIsSheet(&parentIsSheet)) &&
+          parentIsSheet) {
+        piParentWidget->GetSheetWindowParent(&topNonSheetWindow);
+        [NSApp endSheet:nativeParentWindow];
+      }
+
+      nsCOMPtr<nsIWidget> sheetShown;
+      if (NS_SUCCEEDED(piParentWidget->GetChildSheet(
+                           true, getter_AddRefs(sheetShown))) &&
+          (!sheetShown || sheetShown == this)) {
+        // If this sheet is already the sheet actually being shown, don't
+        // tell it to show again. Otherwise the number of calls to
+        // [NSApp beginSheet...] won't match up with [NSApp endSheet...].
+        if (![mWindow isVisible]) {
+          mSheetNeedsShow = false;
+          mSheetWindowParent = topNonSheetWindow;
+          // Only set contextInfo if our parent isn't a sheet.
+          NSWindow* contextInfo = parentIsSheet ? nil : mSheetWindowParent;
+          [TopLevelWindowData deactivateInWindow:mSheetWindowParent];
+          [NSApp beginSheet:mWindow
+             modalForWindow:mSheetWindowParent
+              modalDelegate:mDelegate
+             didEndSelector:@selector(didEndSheet:returnCode:contextInfo:)
+                contextInfo:contextInfo];
+          [TopLevelWindowData activateInWindow:mWindow];
+          SendSetZLevelEvent();
+        }
+      }
+      else {
+        // A sibling of this sheet is active, don't show this sheet yet.
+        // When the active sheet hides, its brothers and sisters that have
+        // mSheetNeedsShow set will have their opportunities to display.
+        mSheetNeedsShow = true;
+      }
+    }
+    else if (mWindowType == eWindowType_popup) {
+      if (!nsCocoaFeatures::OnMojaveOrLater()) {
+        // If a popup window is shown after being hidden, it needs to be "reset"
+        // for it to receive any mouse events aside from mouse-moved events
+        // (because it was removed from the "window cache" when it was hidden
+        // -- see below).  Setting the window number to -1 and then back to its
+        // original value seems to accomplish this.  The idea was "borrowed"
+        // from the Java Embedding Plugin. This is fixed on macOS 10.14+.
+        NSInteger windowNumber = [mWindow windowNumber];
+        [mWindow _setWindowNumber:-1];
+        [mWindow _setWindowNumber:windowNumber];
+      }
+      // For reasons that aren't yet clear, calls to [NSWindow orderFront:] or
+      // [NSWindow makeKeyAndOrderFront:] can sometimes trigger "Error (1000)
+      // creating CGSWindow", which in turn triggers an internal inconsistency
+      // NSException.  These errors shouldn't be fatal.  So we need to wrap
+      // calls to ...orderFront: in TRY blocks.  See bmo bug 470864.
+      NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+      [[mWindow contentView] setNeedsDisplay:YES];
+      [mWindow orderFront:nil];
+      NS_OBJC_END_TRY_ABORT_BLOCK;
+      SendSetZLevelEvent();
+      AdjustWindowShadow();
+      SetWindowBackgroundBlur();
+      // If our popup window is a non-native context menu, tell the OS (and
+      // other programs) that a menu has opened.  This is how the OS knows to
+      // close other programs' context menus when ours open.
+      if ([mWindow isKindOfClass:[PopupWindow class]] &&
+          [(PopupWindow*) mWindow isContextMenu]) {
+        [[NSDistributedNotificationCenter defaultCenter]
+          postNotificationName:@"com.apple.HIToolbox.beginMenuTrackingNotification"
+                        object:@"org.mozilla.gecko.PopupWindow"];
+      }
+
+      // If a parent window was supplied and this is a popup at the parent
+      // level, set its child window. This will cause the child window to
+      // appear above the parent and move when the parent does. Setting this
+      // needs to happen after the _setWindowNumber calls above, otherwise the
+      // window doesn't focus properly.
+      if (nativeParentWindow && mPopupLevel == ePopupLevelParent)
+        [nativeParentWindow addChildWindow:mWindow
+                            ordered:NSWindowAbove];
+    }
+    else {
+      NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+      if (mWindowType == eWindowType_toplevel &&
+          [mWindow respondsToSelector:@selector(setAnimationBehavior:)]) {
+        NSWindowAnimationBehavior behavior;
+        if (mIsAnimationSuppressed) {
+          behavior = NSWindowAnimationBehaviorNone;
+        } else {
+          switch (mAnimationType) {
+            case nsIWidget::eDocumentWindowAnimation:
+              behavior = NSWindowAnimationBehaviorDocumentWindow;
+              break;
+            default:
+              NS_NOTREACHED("unexpected mAnimationType value");
+              // fall through
+            case nsIWidget::eGenericWindowAnimation:
+              behavior = NSWindowAnimationBehaviorDefault;
+              break;
+          }
+        }
+        [mWindow setAnimationBehavior:behavior];
+      }
+      [mWindow makeKeyAndOrderFront:nil];
+      NS_OBJC_END_TRY_ABORT_BLOCK;
+      SendSetZLevelEvent();
+    }
+  }
+  else {
+    // roll up any popups if a top-level window is going away
+    if (mWindowType == eWindowType_toplevel || mWindowType == eWindowType_dialog)
+      RollUpPopups();
+
+    // now get rid of the window/sheet
+    if (mWindowType == eWindowType_sheet) {
+      if (mSheetNeedsShow) {
+        // This is an attempt to hide a sheet that never had a chance to
+        // be shown. There's nothing to do other than make sure that it
+        // won't show.
+        mSheetNeedsShow = false;
+      }
+      else {
+        // get sheet's parent *before* hiding the sheet (which breaks the linkage)
+        NSWindow* sheetParent = mSheetWindowParent;
+        
+        // hide the sheet
+        [NSApp endSheet:mWindow];
+        
+        [TopLevelWindowData deactivateInWindow:mWindow];
+
+        nsCOMPtr<nsIWidget> siblingSheetToShow;
+        bool parentIsSheet = false;
+
+        if (nativeParentWindow && piParentWidget &&
+            NS_SUCCEEDED(piParentWidget->GetChildSheet(
+                             false, getter_AddRefs(siblingSheetToShow))) &&
+            siblingSheetToShow) {
+          // First, give sibling sheets an opportunity to show.
+          siblingSheetToShow->Show(true);
+        }
+        else if (nativeParentWindow && piParentWidget &&
+                 NS_SUCCEEDED(piParentWidget->GetIsSheet(&parentIsSheet)) &&
+                 parentIsSheet) {
+          // Only set contextInfo if the parent of the parent sheet we're about
+          // to restore isn't itself a sheet.
+          NSWindow* contextInfo = sheetParent;
+          nsIWidget* grandparentWidget = nil;
+          if (NS_SUCCEEDED(piParentWidget->GetRealParent(&grandparentWidget)) && grandparentWidget) {
+            nsCOMPtr<nsPIWidgetCocoa> piGrandparentWidget(do_QueryInterface(grandparentWidget));
+            bool grandparentIsSheet = false;
+            if (piGrandparentWidget && NS_SUCCEEDED(piGrandparentWidget->GetIsSheet(&grandparentIsSheet)) &&
+                grandparentIsSheet) {
+                contextInfo = nil;
+            }
+          }
+          // If there are no sibling sheets, but the parent is a sheet, restore
+          // it.  It wasn't sent any deactivate events when it was hidden, so
+          // don't call through Show, just let the OS put it back up.
+          [NSApp beginSheet:nativeParentWindow
+             modalForWindow:sheetParent
+              modalDelegate:[nativeParentWindow delegate]
+             didEndSelector:@selector(didEndSheet:returnCode:contextInfo:)
+                contextInfo:contextInfo];
+        }
+        else {
+          // Sheet, that was hard.  No more siblings or parents, going back
+          // to a real window.
+          NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+          [sheetParent makeKeyAndOrderFront:nil];
+          NS_OBJC_END_TRY_ABORT_BLOCK;
+        }
+        SendSetZLevelEvent();
+      }
+    }
+    else {
+      // If the window is a popup window with a parent window we need to
+      // unhook it here before ordering it out. When you order out the child
+      // of a window it hides the parent window.
+      if (mWindowType == eWindowType_popup && nativeParentWindow)
+        [nativeParentWindow removeChildWindow:mWindow];
+
+      [mWindow orderOut:nil];
+
+      if (!nsCocoaFeatures::OnMojaveOrLater()) {
+        // Unless it's explicitly removed from NSApp's "window cache", a popup
+        // window will keep receiving mouse-moved events even after it's been
+        // "ordered out" (instead of the browser window that was underneath it,
+        // until you click on that window).  This is bmo bug 378645, but it's
+        // surely an Apple bug.  The "window cache" is an undocumented
+        // subsystem, all of whose methods are included in the NSWindowCache
+        // category of the NSApplication class (in header files generated using
+        // class-dump). This workaround was "borrowed" from the Java Embedding
+        // Plugin (which uses it for a different purpose). This is fixed on
+        // macOS 10.14+.
+        if (mWindowType == eWindowType_popup) {
+          [NSApp _removeWindowFromCache:mWindow];
+        }
+      }
+
+      // If our popup window is a non-native context menu, tell the OS (and
+      // other programs) that a menu has closed.
+      if ([mWindow isKindOfClass:[PopupWindow class]] &&
+          [(PopupWindow*) mWindow isContextMenu]) {
+        [[NSDistributedNotificationCenter defaultCenter]
+          postNotificationName:@"com.apple.HIToolbox.endMenuTrackingNotification"
+                        object:@"org.mozilla.gecko.PopupWindow"];
+      }
+    }
+  }
+
+  [mWindow setBeingShown:NO];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+struct ShadowParams {
+  float standardDeviation;
+  float density;
+  int offsetX;
+  int offsetY;
+  unsigned int flags;
+};
+
+// These numbers have been determined by looking at the results of
+// CGSGetWindowShadowAndRimParameters for native window types.
+static const ShadowParams kWindowShadowParametersPreYosemite[] = {
+  { 0.0f, 0.0f, 0, 0, 0 },        // none
+  { 8.0f, 0.5f, 0, 6, 1 },        // default
+  { 10.0f, 0.44f, 0, 10, 512 },   // menu
+  { 8.0f, 0.5f, 0, 6, 1 },        // tooltip
+  { 4.0f, 0.6f, 0, 4, 512 }       // sheet
+};
+
+static const ShadowParams kWindowShadowParametersPostYosemite[] = {
+  { 0.0f, 0.0f, 0, 0, 0 },        // none
+  { 8.0f, 0.5f, 0, 6, 1 },        // default
+  { 9.882353f, 0.3f, 0, 4, 0 },   // menu
+  { 3.294118f, 0.2f, 0, 1, 0 },   // tooltip
+  { 9.882353f, 0.3f, 0, 4, 0 }    // sheet
+};
+
+// This method will adjust the window shadow style for popup windows after
+// they have been made visible. Before they're visible, their window number
+// might be -1, which is not useful.
+// We won't attempt to change the shadow for windows that can acquire key state
+// since OS X will reset the shadow whenever that happens.
+void
+nsCocoaWindow::AdjustWindowShadow()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow || ![mWindow isVisible] || ![mWindow hasShadow] ||
+      [mWindow canBecomeKeyWindow] || [mWindow windowNumber] == -1)
+    return;
+
+  const ShadowParams& params = nsCocoaFeatures::OnYosemiteOrLater()
+    ? kWindowShadowParametersPostYosemite[mShadowStyle]
+    : kWindowShadowParametersPreYosemite[mShadowStyle];
+  CGSConnection cid = _CGSDefaultConnection();
+  CGSSetWindowShadowAndRimParameters(cid, [mWindow windowNumber],
+                                     params.standardDeviation, params.density,
+                                     params.offsetX, params.offsetY,
+                                     params.flags);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const NSUInteger kWindowBackgroundBlurRadius = 4;
+
+void
+nsCocoaWindow::SetWindowBackgroundBlur()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow || ![mWindow isVisible] || [mWindow windowNumber] == -1)
+    return;
+
+  // Only blur the background of menus and fake sheets.
+  if (mShadowStyle != NS_STYLE_WINDOW_SHADOW_MENU &&
+      mShadowStyle != NS_STYLE_WINDOW_SHADOW_SHEET)
+    return;
+
+  CGSConnection cid = _CGSDefaultConnection();
+  CGSSetWindowBackgroundBlurRadius(cid, [mWindow windowNumber], kWindowBackgroundBlurRadius);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsresult
+nsCocoaWindow::ConfigureChildren(const nsTArray<Configuration>& aConfigurations)
+{
+  if (mPopupContentView) {
+    mPopupContentView->ConfigureChildren(aConfigurations);
+  }
+  return NS_OK;
+}
+
+LayerManager*
+nsCocoaWindow::GetLayerManager(PLayerTransactionChild* aShadowManager,
+                               LayersBackend aBackendHint,
+                               LayerManagerPersistence aPersistence)
+{
+  if (mPopupContentView) {
+    return mPopupContentView->GetLayerManager(aShadowManager,
+                                              aBackendHint,
+                                              aPersistence);
+  }
+  return nullptr;
+}
+
+nsTransparencyMode nsCocoaWindow::GetTransparencyMode()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return (!mWindow || [mWindow isOpaque]) ? eTransparencyOpaque : eTransparencyTransparent;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(eTransparencyOpaque);
+}
+
+// This is called from nsMenuPopupFrame when making a popup transparent, or
+// from nsChildView::SetTransparencyMode for other window types.
+void nsCocoaWindow::SetTransparencyMode(nsTransparencyMode aMode)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow)
+    return;
+
+  // Transparent windows are only supported on popups.
+  BOOL isTransparent = aMode == eTransparencyTransparent &&
+                       mWindowType == eWindowType_popup;
+  BOOL currentTransparency = ![mWindow isOpaque];
+  if (isTransparent != currentTransparency) {
+    [mWindow setOpaque:!isTransparent];
+    [mWindow setBackgroundColor:(isTransparent ? [NSColor clearColor] : [NSColor whiteColor])];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::Enable(bool aState)
+{
+  return NS_OK;
+}
+
+bool nsCocoaWindow::IsEnabled() const
+{
+  return true;
+}
+
+#define kWindowPositionSlop 20
+
+void
+nsCocoaWindow::ConstrainPosition(bool aAllowSlop, int32_t *aX, int32_t *aY)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow || ![mWindow screen]) {
+    return;
+  }
+
+  nsIntRect screenBounds;
+
+  int32_t width, height;
+
+  NSRect frame = [mWindow frame];
+
+  // zero size rects confuse the screen manager
+  width = std::max<int32_t>(frame.size.width, 1);
+  height = std::max<int32_t>(frame.size.height, 1);
+
+  nsCOMPtr<nsIScreenManager> screenMgr = do_GetService("@mozilla.org/gfx/screenmanager;1");
+  if (screenMgr) {
+    nsCOMPtr<nsIScreen> screen;
+    screenMgr->ScreenForRect(*aX, *aY, width, height, getter_AddRefs(screen));
+
+    if (screen) {
+      screen->GetRectDisplayPix(&(screenBounds.x), &(screenBounds.y),
+                                &(screenBounds.width), &(screenBounds.height));
+    }
+  }
+
+  if (aAllowSlop) {
+    if (*aX < screenBounds.x - width + kWindowPositionSlop) {
+      *aX = screenBounds.x - width + kWindowPositionSlop;
+    } else if (*aX >= screenBounds.x + screenBounds.width - kWindowPositionSlop) {
+      *aX = screenBounds.x + screenBounds.width - kWindowPositionSlop;
+    }
+
+    if (*aY < screenBounds.y - height + kWindowPositionSlop) {
+      *aY = screenBounds.y - height + kWindowPositionSlop;
+    } else if (*aY >= screenBounds.y + screenBounds.height - kWindowPositionSlop) {
+      *aY = screenBounds.y + screenBounds.height - kWindowPositionSlop;
+    }
+  } else {
+    if (*aX < screenBounds.x) {
+      *aX = screenBounds.x;
+    } else if (*aX >= screenBounds.x + screenBounds.width - width) {
+      *aX = screenBounds.x + screenBounds.width - width;
+    }
+
+    if (*aY < screenBounds.y) {
+      *aY = screenBounds.y;
+    } else if (*aY >= screenBounds.y + screenBounds.height - height) {
+      *aY = screenBounds.y + screenBounds.height - height;
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaWindow::SetSizeConstraints(const SizeConstraints& aConstraints)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Popups can be smaller than (60, 60)
+  NSRect rect =
+    (mWindowType == eWindowType_popup) ? NSZeroRect : NSMakeRect(0.0, 0.0, 60, 60);
+  rect = [mWindow frameRectForContentRect:rect];
+
+  CGFloat scaleFactor = BackingScaleFactor();
+
+  SizeConstraints c = aConstraints;
+  c.mMinSize.width =
+    std::max(nsCocoaUtils::CocoaPointsToDevPixels(rect.size.width, scaleFactor),
+           c.mMinSize.width);
+  c.mMinSize.height =
+    std::max(nsCocoaUtils::CocoaPointsToDevPixels(rect.size.height, scaleFactor),
+           c.mMinSize.height);
+
+  NSSize minSize = {
+    nsCocoaUtils::DevPixelsToCocoaPoints(c.mMinSize.width, scaleFactor),
+    nsCocoaUtils::DevPixelsToCocoaPoints(c.mMinSize.height, scaleFactor)
+  };
+  [mWindow setMinSize:minSize];
+
+  NSSize maxSize = {
+    c.mMaxSize.width == NS_MAXSIZE ?
+      FLT_MAX : nsCocoaUtils::DevPixelsToCocoaPoints(c.mMaxSize.width, scaleFactor),
+    c.mMaxSize.height == NS_MAXSIZE ?
+      FLT_MAX : nsCocoaUtils::DevPixelsToCocoaPoints(c.mMaxSize.height, scaleFactor)
+  };
+  [mWindow setMaxSize:maxSize];
+
+  nsBaseWidget::SetSizeConstraints(c);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Coordinates are desktop pixels
+NS_IMETHODIMP nsCocoaWindow::Move(double aX, double aY)
+{
+  if (!mWindow) {
+    return NS_OK;
+  }
+
+  // The point we have is in Gecko coordinates (origin top-left). Convert
+  // it to Cocoa ones (origin bottom-left).
+  NSPoint coord = {
+    static_cast<float>(aX),
+    static_cast<float>(nsCocoaUtils::FlippedScreenY(NSToIntRound(aY)))
+  };
+
+  NSRect frame = [mWindow frame];
+  if (frame.origin.x != coord.x ||
+      frame.origin.y + frame.size.height != coord.y) {
+    [mWindow setFrameTopLeftPoint:coord];
+  }
+
+  return NS_OK;
+}
+
+void
+nsCocoaWindow::SetSizeMode(nsSizeMode aMode)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow)
+    return;
+
+  // mSizeMode will be updated in DispatchSizeModeEvent, which will be called
+  // from a delegate method that handles the state change during one of the
+  // calls below.
+  nsSizeMode previousMode = mSizeMode;
+
+  if (aMode == nsSizeMode_Normal) {
+    if ([mWindow isMiniaturized])
+      [mWindow deminiaturize:nil];
+    else if (previousMode == nsSizeMode_Maximized && [mWindow isZoomed])
+      [mWindow zoom:nil];
+  }
+  else if (aMode == nsSizeMode_Minimized) {
+    if (![mWindow isMiniaturized])
+      [mWindow miniaturize:nil];
+  }
+  else if (aMode == nsSizeMode_Maximized) {
+    if ([mWindow isMiniaturized])
+      [mWindow deminiaturize:nil];
+    if (![mWindow isZoomed])
+      [mWindow zoom:nil];
+  }
+  else if (aMode == nsSizeMode_Fullscreen) {
+    if (!mInFullScreenMode)
+      MakeFullScreen(true);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// This has to preserve the window's frame bounds.
+// This method requires (as does the Windows impl.) that you call Resize shortly
+// after calling HideWindowChrome. See bug 498835 for fixing this.
+NS_IMETHODIMP nsCocoaWindow::HideWindowChrome(bool aShouldHide)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!mWindow || !mWindowMadeHere ||
+      (mWindowType != eWindowType_toplevel && mWindowType != eWindowType_dialog))
+    return NS_ERROR_FAILURE;
+
+  BOOL isVisible = [mWindow isVisible];
+
+  // Remove child windows.
+  NSArray* childWindows = [mWindow childWindows];
+  NSEnumerator* enumerator = [childWindows objectEnumerator];
+  NSWindow* child = nil;
+  while ((child = [enumerator nextObject])) {
+    [mWindow removeChildWindow:child];
+  }
+
+  // Remove the content view.
+  NSView* contentView = [mWindow contentView];
+  [contentView retain];
+  [contentView removeFromSuperviewWithoutNeedingDisplay];
+
+  // Save state (like window title).
+  NSMutableDictionary* state = [mWindow exportState];
+
+  // Recreate the window with the right border style.
+  NSRect frameRect = [mWindow frame];
+  DestroyNativeWindow();
+  nsresult rv = CreateNativeWindow(frameRect, aShouldHide ? eBorderStyle_none : mBorderStyle, true);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Re-import state.
+  [mWindow importState:state];
+
+  // Reparent the content view.
+  [mWindow setContentView:contentView];
+  [contentView release];
+
+  // Reparent child windows.
+  enumerator = [childWindows objectEnumerator];
+  while ((child = [enumerator nextObject])) {
+    [mWindow addChildWindow:child ordered:NSWindowAbove];
+  }
+
+  // Show the new window.
+  if (isVisible) {
+    bool wasAnimationSuppressed = mIsAnimationSuppressed;
+    mIsAnimationSuppressed = true;
+    rv = Show(true);
+    mIsAnimationSuppressed = wasAnimationSuppressed;
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+class FullscreenTransitionData : public nsISupports
+{
+public:
+  NS_DECL_ISUPPORTS
+
+  explicit FullscreenTransitionData(NSWindow* aWindow)
+    : mTransitionWindow(aWindow) { }
+
+  NSWindow* mTransitionWindow;
+
+private:
+  virtual ~FullscreenTransitionData()
+  {
+    [mTransitionWindow close];
+  }
+};
+
+NS_IMPL_ISUPPORTS0(FullscreenTransitionData)
+
+@interface FullscreenTransitionDelegate : NSObject <NSAnimationDelegate>
+{
+@public
+  nsCocoaWindow* mWindow;
+  nsIRunnable* mCallback;
+}
+@end
+
+@implementation FullscreenTransitionDelegate
+- (void)cleanupAndDispatch:(NSAnimation* )animation
+{
+  [animation setDelegate:nil];
+  [self autorelease];
+  // The caller should have added ref for us.
+  NS_DispatchToMainThread(already_AddRefed<nsIRunnable>(mCallback));
+}
+
+- (void)animationDidEnd:(NSAnimation *)animation
+{
+  MOZ_ASSERT(animation == mWindow->FullscreenTransitionAnimation(),
+             "Should be handling the only animation on the window");
+  mWindow->ReleaseFullscreenTransitionAnimation();
+  [self cleanupAndDispatch:animation];
+}
+
+- (void)animationDidStop:(NSAnimation *)animation
+{
+  [self cleanupAndDispatch:animation];
+}
+@end
+
+/* virtual */ bool
+nsCocoaWindow::PrepareForFullscreenTransition(nsISupports** aData)
+{
+  nsCOMPtr<nsIScreen> widgetScreen = GetWidgetScreen();
+  nsScreenCocoa* screen = static_cast<nsScreenCocoa*>(widgetScreen.get());
+  NSScreen* cocoaScreen = screen->CocoaScreen();
+
+  NSWindow* win =
+    [[NSWindow alloc] initWithContentRect:[cocoaScreen frame]
+                                styleMask:NSBorderlessWindowMask
+                                  backing:NSBackingStoreBuffered
+                                    defer:YES];
+  [win setBackgroundColor:[NSColor blackColor]];
+  [win setAlphaValue:0];
+  [win setIgnoresMouseEvents:YES];
+  [win setLevel:NSScreenSaverWindowLevel];
+  [win makeKeyAndOrderFront:nil];
+
+  auto data = new FullscreenTransitionData(win);
+  *aData = data;
+  NS_ADDREF(data);
+  return true;
+}
+
+/* virtual */ void
+nsCocoaWindow::PerformFullscreenTransition(FullscreenTransitionStage aStage,
+                                           uint16_t aDuration,
+                                           nsISupports* aData,
+                                           nsIRunnable* aCallback)
+{
+  auto data = static_cast<FullscreenTransitionData*>(aData);
+  FullscreenTransitionDelegate* delegate =
+    [[FullscreenTransitionDelegate alloc] init];
+  delegate->mWindow = this;
+  // Storing already_AddRefed directly could cause static checking fail.
+  delegate->mCallback = nsCOMPtr<nsIRunnable>(aCallback).forget().take();
+
+  if (mFullscreenTransitionAnimation) {
+    [mFullscreenTransitionAnimation stopAnimation];
+    ReleaseFullscreenTransitionAnimation();
+  }
+
+  NSDictionary* dict = @{
+    NSViewAnimationTargetKey: data->mTransitionWindow,
+    NSViewAnimationEffectKey: aStage == eBeforeFullscreenToggle ?
+      NSViewAnimationFadeInEffect : NSViewAnimationFadeOutEffect
+  };
+  mFullscreenTransitionAnimation =
+    [[NSViewAnimation alloc] initWithViewAnimations:@[dict]];
+  [mFullscreenTransitionAnimation setDelegate:delegate];
+  [mFullscreenTransitionAnimation setDuration:aDuration / 1000.0];
+  [mFullscreenTransitionAnimation startAnimation];
+}
+
+void nsCocoaWindow::EnteredFullScreen(bool aFullScreen, bool aNativeMode)
+{
+  mInFullScreenTransition = false;
+  bool wasInFullscreen = mInFullScreenMode;
+  mInFullScreenMode = aFullScreen;
+  if (aNativeMode || mInNativeFullScreenMode) {
+    mInNativeFullScreenMode = aFullScreen;
+  }
+  DispatchSizeModeEvent();
+  if (mWidgetListener && wasInFullscreen != aFullScreen) {
+    mWidgetListener->FullscreenChanged(aFullScreen);
+  }
+}
+
+inline bool
+nsCocoaWindow::ShouldToggleNativeFullscreen(bool aFullScreen,
+                                            bool aUseSystemTransition)
+{
+  if (!mSupportsNativeFullScreen) {
+    // If we cannot use native fullscreen, don't touch it.
+    return false;
+  }
+  if (mInNativeFullScreenMode) {
+    // If we are using native fullscreen, go ahead to exit it.
+    return true;
+  }
+  if (!aUseSystemTransition) {
+    // If we do not want the system fullscreen transition,
+    // don't use the native fullscreen.
+    return false;
+  }
+  // If we are using native fullscreen, we should have returned earlier.
+  return aFullScreen;
+}
+
+nsresult
+nsCocoaWindow::MakeFullScreen(bool aFullScreen, nsIScreen* aTargetScreen)
+{
+  return DoMakeFullScreen(aFullScreen, false);
+}
+
+NS_IMETHODIMP
+nsCocoaWindow::MakeFullScreenWithNativeTransition(bool aFullScreen,
+                                                  nsIScreen* aTargetScreen)
+{
+  return DoMakeFullScreen(aFullScreen, true);
+}
+
+nsresult
+nsCocoaWindow::DoMakeFullScreen(bool aFullScreen, bool aUseSystemTransition)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!mWindow) {
+    return NS_OK;
+  }
+
+  // We will call into MakeFullScreen redundantly when entering/exiting
+  // fullscreen mode via OS X controls. When that happens we should just handle
+  // it gracefully - no need to ASSERT.
+  if (mInFullScreenMode == aFullScreen) {
+    return NS_OK;
+  }
+
+  mInFullScreenTransition = true;
+
+  if (ShouldToggleNativeFullscreen(aFullScreen, aUseSystemTransition)) {
+    // If we're using native fullscreen mode and our native window is invisible,
+    // our attempt to go into fullscreen mode will fail with an assertion in
+    // system code, without [WindowDelegate windowDidFailToEnterFullScreen:]
+    // ever getting called.  To pre-empt this we bail here.  See bug 752294.
+    if (aFullScreen && ![mWindow isVisible]) {
+      EnteredFullScreen(false);
+      return NS_OK;
+    }
+    MOZ_ASSERT(mInNativeFullScreenMode != aFullScreen,
+               "We shouldn't have been in native fullscreen.");
+    // Calling toggleFullScreen will result in windowDid(FailTo)?(Enter|Exit)FullScreen
+    // to be called from the OS. We will call EnteredFullScreen from those methods,
+    // where mInFullScreenMode will be set and a sizemode event will be dispatched.
+    [mWindow toggleFullScreen:nil];
+  } else {
+    NSDisableScreenUpdates();
+    // The order here matters. When we exit full screen mode, we need to show the
+    // Dock first, otherwise the newly-created window won't have its minimize
+    // button enabled. See bug 526282.
+    nsCocoaUtils::HideOSChromeOnScreen(aFullScreen);
+    nsBaseWidget::InfallibleMakeFullScreen(aFullScreen);
+    NSEnableScreenUpdates();
+    EnteredFullScreen(aFullScreen, /* aNativeMode */ false);
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Coordinates are desktop pixels
+nsresult nsCocoaWindow::DoResize(double aX, double aY,
+                                 double aWidth, double aHeight,
+                                 bool aRepaint,
+                                 bool aConstrainToCurrentScreen)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!mWindow || mInResize) {
+    return NS_OK;
+  }
+
+  AutoRestore<bool> reentrantResizeGuard(mInResize);
+  mInResize = true;
+
+  // ConstrainSize operates in device pixels, so we need to convert using
+  // the backing scale factor here
+  CGFloat scale = BackingScaleFactor();
+  int32_t width = NSToIntRound(aWidth * scale);
+  int32_t height = NSToIntRound(aHeight * scale);
+  ConstrainSize(&width, &height);
+
+  DesktopIntRect newBounds(NSToIntRound(aX), NSToIntRound(aY),
+                           NSToIntRound(width / scale),
+                           NSToIntRound(height / scale));
+
+  // constrain to the screen that contains the largest area of the new rect
+  FitRectToVisibleAreaForScreen(newBounds, aConstrainToCurrentScreen ?
+                                           [mWindow screen] : nullptr);
+
+  // convert requested bounds into Cocoa coordinate system
+  NSRect newFrame = nsCocoaUtils::GeckoRectToCocoaRect(newBounds);
+
+  NSRect frame = [mWindow frame];
+  BOOL isMoving = newFrame.origin.x != frame.origin.x ||
+                  newFrame.origin.y != frame.origin.y;
+  BOOL isResizing = newFrame.size.width != frame.size.width ||
+                    newFrame.size.height != frame.size.height;
+
+  if (!isMoving && !isResizing) {
+    return NS_OK;
+  }
+
+  // We ignore aRepaint -- we have to call display:YES, otherwise the
+  // title bar doesn't immediately get repainted and is displayed in
+  // the wrong place, leading to a visual jump.
+  [mWindow setFrame:newFrame display:YES];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Coordinates are desktop pixels
+NS_IMETHODIMP nsCocoaWindow::Resize(double aX, double aY,
+                                    double aWidth, double aHeight,
+                                    bool aRepaint)
+{
+  return DoResize(aX, aY, aWidth, aHeight, aRepaint, false);
+}
+
+// Coordinates are desktop pixels
+NS_IMETHODIMP nsCocoaWindow::Resize(double aWidth, double aHeight, bool aRepaint)
+{
+  double invScale = 1.0 / BackingScaleFactor();
+  return DoResize(mBounds.x * invScale, mBounds.y * invScale,
+                  aWidth, aHeight, aRepaint, true);
+}
+
+LayoutDeviceIntRect
+nsCocoaWindow::GetClientBounds()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  CGFloat scaleFactor = BackingScaleFactor();
+  if (!mWindow) {
+    return nsCocoaUtils::CocoaRectToGeckoRectDevPix(NSZeroRect, scaleFactor);
+  }
+
+  NSRect r;
+  if ([mWindow isKindOfClass:[ToolbarWindow class]] &&
+      [(ToolbarWindow*)mWindow drawsContentsIntoWindowFrame]) {
+    r = [mWindow frame];
+  } else {
+    r = [mWindow contentRectForFrameRect:[mWindow frame]];
+  }
+
+  return nsCocoaUtils::CocoaRectToGeckoRectDevPix(r, scaleFactor);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(LayoutDeviceIntRect(0, 0, 0, 0));
+}
+
+void
+nsCocoaWindow::UpdateBounds()
+{
+  NSRect frame = NSZeroRect;
+  if (mWindow) {
+    frame = [mWindow frame];
+  }
+  mBounds =
+    nsCocoaUtils::CocoaRectToGeckoRectDevPix(frame, BackingScaleFactor());
+}
+
+LayoutDeviceIntRect
+nsCocoaWindow::GetScreenBounds()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+#ifdef DEBUG
+  LayoutDeviceIntRect r = nsCocoaUtils::CocoaRectToGeckoRectDevPix([mWindow frame], BackingScaleFactor());
+  NS_ASSERTION(mWindow && mBounds == r, "mBounds out of sync!");
+#endif
+
+  return mBounds;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(LayoutDeviceIntRect(0, 0, 0, 0));
+}
+
+double
+nsCocoaWindow::GetDefaultScaleInternal()
+{
+  return BackingScaleFactor();
+}
+
+static CGFloat
+GetBackingScaleFactor(NSWindow* aWindow)
+{
+  NSRect frame = [aWindow frame];
+  if (frame.size.width > 0 && frame.size.height > 0) {
+    return nsCocoaUtils::GetBackingScaleFactor(aWindow);
+  }
+
+  // For windows with zero width or height, the backingScaleFactor method
+  // is broken - it will always return 2 on a retina macbook, even when
+  // the window position implies it's on a non-hidpi external display
+  // (to the extent that a zero-area window can be said to be "on" a
+  // display at all!)
+  // And to make matters worse, Cocoa even fires a
+  // windowDidChangeBackingProperties notification with the
+  // NSBackingPropertyOldScaleFactorKey key when a window on an
+  // external display is resized to/from zero height, even though it hasn't
+  // really changed screens.
+
+  // This causes us to handle popup window sizing incorrectly when the
+  // popup is resized to zero height (bug 820327) - nsXULPopupManager
+  // becomes (incorrectly) convinced the popup has been explicitly forced
+  // to a non-default size and needs to have size attributes attached.
+
+  // Workaround: instead of asking the window, we'll find the screen it is on
+  // and ask that for *its* backing scale factor.
+
+  // (See bug 853252 and additional comments in windowDidChangeScreen: below
+  // for further complications this causes.)
+
+  // First, expand the rect so that it actually has a measurable area,
+  // for FindTargetScreenForRect to use.
+  if (frame.size.width == 0) {
+    frame.size.width = 1;
+  }
+  if (frame.size.height == 0) {
+    frame.size.height = 1;
+  }
+
+  // Then identify the screen it belongs to, and return its scale factor.
+  NSScreen *screen =
+    FindTargetScreenForRect(nsCocoaUtils::CocoaRectToGeckoRect(frame));
+  return nsCocoaUtils::GetBackingScaleFactor(screen);
+}
+
+CGFloat
+nsCocoaWindow::BackingScaleFactor()
+{
+  if (mBackingScaleFactor > 0.0) {
+    return mBackingScaleFactor;
+  }
+  if (!mWindow) {
+    return 1.0;
+  }
+  mBackingScaleFactor = GetBackingScaleFactor(mWindow);
+  return mBackingScaleFactor;
+}
+
+void
+nsCocoaWindow::BackingScaleFactorChanged()
+{
+  CGFloat newScale = GetBackingScaleFactor(mWindow);
+
+  // ignore notification if it hasn't really changed (or maybe we have
+  // disabled HiDPI mode via prefs)
+  if (mBackingScaleFactor == newScale) {
+    return;
+  }
+
+  if (mBackingScaleFactor > 0.0) {
+    // convert size constraints to the new device pixel coordinate space
+    double scaleFactor = newScale / mBackingScaleFactor;
+    mSizeConstraints.mMinSize.width =
+      NSToIntRound(mSizeConstraints.mMinSize.width * scaleFactor);
+    mSizeConstraints.mMinSize.height =
+      NSToIntRound(mSizeConstraints.mMinSize.height * scaleFactor);
+    if (mSizeConstraints.mMaxSize.width < NS_MAXSIZE) {
+      mSizeConstraints.mMaxSize.width =
+        std::min(NS_MAXSIZE,
+               NSToIntRound(mSizeConstraints.mMaxSize.width * scaleFactor));
+    }
+    if (mSizeConstraints.mMaxSize.height < NS_MAXSIZE) {
+      mSizeConstraints.mMaxSize.height =
+        std::min(NS_MAXSIZE,
+               NSToIntRound(mSizeConstraints.mMaxSize.height * scaleFactor));
+    }
+  }
+
+  mBackingScaleFactor = newScale;
+
+  if (!mWidgetListener || mWidgetListener->GetXULWindow()) {
+    return;
+  }
+
+  nsIPresShell* presShell = mWidgetListener->GetPresShell();
+  if (presShell) {
+    presShell->BackingScaleFactorChanged();
+  }
+}
+
+int32_t
+nsCocoaWindow::RoundsWidgetCoordinatesTo()
+{
+  if (BackingScaleFactor() == 2.0) {
+    return 2;
+  }
+  return 1;
+}
+
+NS_IMETHODIMP nsCocoaWindow::SetCursor(nsCursor aCursor)
+{
+  if (mPopupContentView)
+    return mPopupContentView->SetCursor(aCursor);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::SetCursor(imgIContainer* aCursor,
+                                       uint32_t aHotspotX, uint32_t aHotspotY)
+{
+  if (mPopupContentView)
+    return mPopupContentView->SetCursor(aCursor, aHotspotX, aHotspotY);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::SetTitle(const nsAString& aTitle)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!mWindow)
+    return NS_OK;
+
+  const nsString& strTitle = PromiseFlatString(aTitle);
+  NSString* title = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(strTitle.get())
+                                            length:strTitle.Length()];
+
+  if ([mWindow drawsContentsIntoWindowFrame] && ![mWindow wantsTitleDrawn]) {
+    // Don't cause invalidations.
+    [mWindow disableSetNeedsDisplay];
+    [mWindow setTitle:title];
+    [mWindow enableSetNeedsDisplay];
+  } else {
+    [mWindow setTitle:title];
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsCocoaWindow::Invalidate(const LayoutDeviceIntRect& aRect)
+{
+  if (mPopupContentView) {
+    return mPopupContentView->Invalidate(aRect);
+  }
+
+  return NS_OK;
+}
+
+// Pass notification of some drag event to Gecko
+//
+// The drag manager has let us know that something related to a drag has
+// occurred in this window. It could be any number of things, ranging from 
+// a drop, to a drag enter/leave, or a drag over event. The actual event
+// is passed in |aMessage| and is passed along to our event hanlder so Gecko
+// knows about it.
+bool nsCocoaWindow::DragEvent(unsigned int aMessage, mozilla::gfx::Point aMouseGlobal, UInt16 aKeyModifiers)
+{
+  return false;
+}
+
+NS_IMETHODIMP nsCocoaWindow::SendSetZLevelEvent()
+{
+  nsWindowZ placement = nsWindowZTop;
+  nsCOMPtr<nsIWidget> actualBelow;
+  if (mWidgetListener)
+    mWidgetListener->ZLevelChanged(true, &placement, nullptr, getter_AddRefs(actualBelow));
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::GetChildSheet(bool aShown, nsIWidget** _retval)
+{
+  nsIWidget* child = GetFirstChild();
+
+  while (child) {
+    if (child->WindowType() == eWindowType_sheet) {
+      // if it's a sheet, it must be an nsCocoaWindow
+      nsCocoaWindow* cocoaWindow = static_cast<nsCocoaWindow*>(child);
+      if (cocoaWindow->mWindow &&
+          ((aShown && [cocoaWindow->mWindow isVisible]) ||
+          (!aShown && cocoaWindow->mSheetNeedsShow))) {
+        nsCOMPtr<nsIWidget> widget = cocoaWindow;
+        widget.forget(_retval);
+        return NS_OK;
+      }
+    }
+    child = child->GetNextSibling();
+  }
+
+  *_retval = nullptr;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::GetRealParent(nsIWidget** parent)
+{
+  *parent = mParent;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::GetIsSheet(bool* isSheet)
+{
+  mWindowType == eWindowType_sheet ? *isSheet = true : *isSheet = false;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::GetSheetWindowParent(NSWindow** sheetWindowParent)
+{
+  *sheetWindowParent = mSheetWindowParent;
+  return NS_OK;
+}
+
+// Invokes callback and ProcessEvent methods on Event Listener object
+NS_IMETHODIMP 
+nsCocoaWindow::DispatchEvent(WidgetGUIEvent* event, nsEventStatus& aStatus)
+{
+  aStatus = nsEventStatus_eIgnore;
+
+  nsCOMPtr<nsIWidget> kungFuDeathGrip(event->mWidget);
+  mozilla::Unused << kungFuDeathGrip; // Not used within this function
+
+  if (mWidgetListener)
+    aStatus = mWidgetListener->HandleEvent(event, mUseAttachedEvents);
+
+  return NS_OK;
+}
+
+// aFullScreen should be the window's mInFullScreenMode. We don't have access to that
+// from here, so we need to pass it in. mInFullScreenMode should be the canonical
+// indicator that a window is currently full screen and it makes sense to keep
+// all sizemode logic here.
+static nsSizeMode
+GetWindowSizeMode(NSWindow* aWindow, bool aFullScreen) {
+  if (aFullScreen)
+    return nsSizeMode_Fullscreen;
+  if ([aWindow isMiniaturized])
+    return nsSizeMode_Minimized;
+  if (([aWindow styleMask] & NSResizableWindowMask) && [aWindow isZoomed])
+    return nsSizeMode_Maximized;
+  return nsSizeMode_Normal;
+}
+
+void
+nsCocoaWindow::ReportMoveEvent()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Prevent recursion, which can become infinite (see bug 708278).  This
+  // can happen when the call to [NSWindow setFrameTopLeftPoint:] in
+  // nsCocoaWindow::Move() triggers an immediate NSWindowDidMove notification
+  // (and a call to [WindowDelegate windowDidMove:]).
+  if (mInReportMoveEvent) {
+    return;
+  }
+  mInReportMoveEvent = true;
+
+  UpdateBounds();
+
+  // Dispatch the move event to Gecko
+  NotifyWindowMoved(mBounds.x, mBounds.y);
+
+  mInReportMoveEvent = false;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsCocoaWindow::DispatchSizeModeEvent()
+{
+  if (!mWindow) {
+    return;
+  }
+
+  nsSizeMode newMode = GetWindowSizeMode(mWindow, mInFullScreenMode);
+
+  // Don't dispatch a sizemode event if:
+  // 1. the window is transitioning to fullscreen
+  // 2. the new sizemode is the same as the current sizemode
+  if (mInFullScreenTransition || mSizeMode == newMode) {
+    return;
+  }
+
+  mSizeMode = newMode;
+  if (mWidgetListener) {
+    mWidgetListener->SizeModeChanged(newMode);
+  }
+}
+
+void
+nsCocoaWindow::ReportSizeEvent()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  UpdateBounds();
+
+  if (mWidgetListener) {
+    LayoutDeviceIntRect innerBounds = GetClientBounds();
+    mWidgetListener->WindowResized(this, innerBounds.width, innerBounds.height);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaWindow::SetMenuBar(nsMenuBarX *aMenuBar)
+{
+  if (mMenuBar)
+    mMenuBar->SetParent(nullptr);
+  if (!mWindow) {
+    mMenuBar = nullptr;
+    return;
+  }
+  mMenuBar = aMenuBar;
+
+  // Only paint for active windows, or paint the hidden window menu bar if no
+  // other menu bar has been painted yet so that some reasonable menu bar is
+  // displayed when the app starts up.
+  id windowDelegate = [mWindow delegate];
+  if (mMenuBar &&
+      ((!gSomeMenuBarPainted && nsMenuUtilsX::GetHiddenWindowMenuBar() == mMenuBar) ||
+       (windowDelegate && [windowDelegate toplevelActiveState])))
+    mMenuBar->Paint();
+}
+
+NS_IMETHODIMP nsCocoaWindow::SetFocus(bool aState)
+{
+  if (!mWindow)
+    return NS_OK;
+
+  if (mPopupContentView) {
+    mPopupContentView->SetFocus(aState);
+  }
+  else if (aState && ([mWindow isVisible] || [mWindow isMiniaturized])) {
+    if ([mWindow isMiniaturized]) {
+      [mWindow deminiaturize:nil];
+    }
+
+    [mWindow makeKeyAndOrderFront:nil];
+    SendSetZLevelEvent();
+  }
+
+  return NS_OK;
+}
+
+LayoutDeviceIntPoint nsCocoaWindow::WidgetToScreenOffset()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NSRect rect = NSZeroRect;
+  LayoutDeviceIntRect r;
+  if (mWindow) {
+    rect = [mWindow contentRectForFrameRect:[mWindow frame]];
+  }
+  r = nsCocoaUtils::CocoaRectToGeckoRectDevPix(rect, BackingScaleFactor());
+
+  return r.TopLeft();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(LayoutDeviceIntPoint(0,0));
+}
+
+LayoutDeviceIntPoint nsCocoaWindow::GetClientOffset()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  LayoutDeviceIntRect clientRect = GetClientBounds();
+
+  return clientRect.TopLeft() - mBounds.TopLeft();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(LayoutDeviceIntPoint(0, 0));
+}
+
+LayoutDeviceIntSize
+nsCocoaWindow::ClientToWindowSize(const LayoutDeviceIntSize& aClientSize)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (!mWindow)
+    return LayoutDeviceIntSize(0, 0);
+
+  CGFloat backingScale = BackingScaleFactor();
+  LayoutDeviceIntRect r(0, 0, aClientSize.width, aClientSize.height);
+  NSRect rect = nsCocoaUtils::DevPixelsToCocoaPoints(r, backingScale);
+
+  NSRect inflatedRect = [mWindow frameRectForContentRect:rect];
+  r = nsCocoaUtils::CocoaRectToGeckoRectDevPix(inflatedRect, backingScale);
+  return r.Size();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(LayoutDeviceIntSize(0,0));
+}
+
+nsMenuBarX* nsCocoaWindow::GetMenuBar()
+{
+  return mMenuBar;
+}
+
+void
+nsCocoaWindow::CaptureRollupEvents(nsIRollupListener* aListener,
+                                   bool aDoCapture)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  gRollupListener = nullptr;
+  
+  if (aDoCapture) {
+    if (![NSApp isActive]) {
+      // We need to capture mouse event if we aren't
+      // the active application. We only set this up when needed
+      // because they cause spurious mouse event after crash
+      // and gdb sessions. See bug 699538.
+      nsToolkit::GetToolkit()->RegisterForAllProcessMouseEvents();
+    }
+    gRollupListener = aListener;
+
+    // Sometimes more than one popup window can be visible at the same time
+    // (e.g. nested non-native context menus, or the test case (attachment
+    // 276885) for bmo bug 392389, which displays a non-native combo-box in a
+    // non-native popup window).  In these cases the "active" popup window should
+    // be the topmost -- the (nested) context menu the mouse is currently over,
+    // or the combo-box's drop-down list (when it's displayed).  But (among
+    // windows that have the same "level") OS X makes topmost the window that
+    // last received a mouse-down event, which may be incorrect (in the combo-
+    // box case, it makes topmost the window containing the combo-box).  So
+    // here we fiddle with a non-native popup window's level to make sure the
+    // "active" one is always above any other non-native popup windows that
+    // may be visible.
+    if (mWindow && (mWindowType == eWindowType_popup))
+      SetPopupWindowLevel();
+  } else {
+    nsToolkit::GetToolkit()->UnregisterAllProcessMouseEventHandlers();
+
+    // XXXndeakin this doesn't make sense.
+    // Why is the new window assumed to be a modal panel?
+    if (mWindow && (mWindowType == eWindowType_popup))
+      [mWindow setLevel:NSModalPanelWindowLevel];
+  }
+  
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::GetAttention(int32_t aCycleCount)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  [NSApp requestUserAttention:NSInformationalRequest];
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+bool
+nsCocoaWindow::HasPendingInputEvent()
+{
+  return nsChildView::DoHasPendingInputEvent();
+}
+
+void
+nsCocoaWindow::SetWindowShadowStyle(int32_t aStyle)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow)
+    return;
+
+  mShadowStyle = aStyle;
+
+  // Shadowless windows are only supported on popups.
+  if (mWindowType == eWindowType_popup)
+    [mWindow setHasShadow:(aStyle != NS_STYLE_WINDOW_SHADOW_NONE)];
+
+  [mWindow setUseMenuStyle:(aStyle == NS_STYLE_WINDOW_SHADOW_MENU)];
+  AdjustWindowShadow();
+  SetWindowBackgroundBlur();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaWindow::SetShowsToolbarButton(bool aShow)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mWindow)
+    [mWindow setShowsToolbarButton:aShow];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaWindow::SetShowsFullScreenButton(bool aShow)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow || ![mWindow respondsToSelector:@selector(toggleFullScreen:)] ||
+      mSupportsNativeFullScreen == aShow) {
+    return;
+  }
+
+  // If the window is currently in fullscreen mode, then we're going to
+  // transition out first, then set the collection behavior & toggle
+  // mSupportsNativeFullScreen, then transtion back into fullscreen mode. This
+  // prevents us from getting into a conflicting state with MakeFullScreen
+  // where mSupportsNativeFullScreen would lead us down the wrong path.
+  bool wasFullScreen = mInFullScreenMode;
+
+  if (wasFullScreen) {
+    MakeFullScreen(false);
+  }
+
+  NSWindowCollectionBehavior newBehavior = [mWindow collectionBehavior];
+  if (aShow) {
+    newBehavior |= NSWindowCollectionBehaviorFullScreenPrimary;
+  } else {
+    newBehavior &= ~NSWindowCollectionBehaviorFullScreenPrimary;
+  }
+  [mWindow setCollectionBehavior:newBehavior];
+  mSupportsNativeFullScreen = aShow;
+
+  if (wasFullScreen) {
+    MakeFullScreen(true);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaWindow::SetWindowAnimationType(nsIWidget::WindowAnimationType aType)
+{
+  mAnimationType = aType;
+}
+
+void
+nsCocoaWindow::SetDrawsTitle(bool aDrawTitle)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mWindow setWantsTitleDrawn:aDrawTitle];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsCocoaWindow::SetUseBrightTitlebarForeground(bool aBrightForeground)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mWindow setUseBrightTitlebarForeground:aBrightForeground];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::SetNonClientMargins(LayoutDeviceIntMargin &margins)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  SetDrawsInTitlebar(margins.top == 0);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void
+nsCocoaWindow::SetWindowTitlebarColor(nscolor aColor, bool aActive)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mWindow)
+    return;
+
+  // If they pass a color with a complete transparent alpha component, use the
+  // native titlebar appearance.
+  if (NS_GET_A(aColor) == 0) {
+    [mWindow setTitlebarColor:nil forActiveWindow:(BOOL)aActive]; 
+  } else {
+    // Transform from sRGBA to monitor RGBA. This seems like it would make trying
+    // to match the system appearance lame, so probably we just shouldn't color 
+    // correct chrome.
+    if (gfxPlatform::GetCMSMode() == eCMSMode_All) {
+      qcms_transform *transform = gfxPlatform::GetCMSRGBATransform();
+      if (transform) {
+        uint8_t color[3];
+        color[0] = NS_GET_R(aColor);
+        color[1] = NS_GET_G(aColor);
+        color[2] = NS_GET_B(aColor);
+        qcms_transform_data(transform, color, color, 1);
+        aColor = NS_RGB(color[0], color[1], color[2]);
+      }
+    }
+
+    [mWindow setTitlebarColor:[NSColor colorWithDeviceRed:NS_GET_R(aColor)/255.0
+                                                    green:NS_GET_G(aColor)/255.0
+                                                     blue:NS_GET_B(aColor)/255.0
+                                                    alpha:NS_GET_A(aColor)/255.0]
+              forActiveWindow:(BOOL)aActive];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaWindow::SetDrawsInTitlebar(bool aState)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mWindow)
+    [mWindow setDrawsContentsIntoWindowFrame:aState];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP nsCocoaWindow::SynthesizeNativeMouseEvent(LayoutDeviceIntPoint aPoint,
+                                                        uint32_t aNativeMessage,
+                                                        uint32_t aModifierFlags,
+                                                        nsIObserver* aObserver)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  AutoObserverNotifier notifier(aObserver, "mouseevent");
+  if (mPopupContentView)
+    return mPopupContentView->SynthesizeNativeMouseEvent(aPoint, aNativeMessage,
+                                                         aModifierFlags, nullptr);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void nsCocoaWindow::UpdateThemeGeometries(const nsTArray<ThemeGeometry>& aThemeGeometries) {
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mPopupContentView) {
+    return mPopupContentView->UpdateThemeGeometries(aThemeGeometries);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsCocoaWindow::SetPopupWindowLevel()
+{
+  if (!mWindow)
+    return;
+
+  // Floating popups are at the floating level and hide when the window is
+  // deactivated.
+  if (mPopupLevel == ePopupLevelFloating) {
+    [mWindow setLevel:NSFloatingWindowLevel];
+    [mWindow setHidesOnDeactivate:YES];
+  }
+  else {
+    // Otherwise, this is a top-level or parent popup. Parent popups always
+    // appear just above their parent and essentially ignore the level.
+    [mWindow setLevel:NSPopUpMenuWindowLevel];
+    [mWindow setHidesOnDeactivate:NO];
+  }
+}
+
+NS_IMETHODIMP_(void)
+nsCocoaWindow::SetInputContext(const InputContext& aContext,
+                               const InputContextAction& aAction)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  mInputContext = aContext;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP_(bool)
+nsCocoaWindow::ExecuteNativeKeyBinding(NativeKeyBindingsType aType,
+                                       const WidgetKeyboardEvent& aEvent,
+                                       DoCommandCallback aCallback,
+                                       void* aCallbackData)
+{
+  NativeKeyBindings* keyBindings = NativeKeyBindings::GetInstance(aType);
+  return keyBindings->Execute(aEvent, aCallback, aCallbackData);
+}
+
+@implementation WindowDelegate
+
+// We try to find a gecko menu bar to paint. If one does not exist, just paint
+// the application menu by itself so that a window doesn't have some other
+// window's menu bar.
++ (void)paintMenubarForWindow:(NSWindow*)aWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // make sure we only act on windows that have this kind of
+  // object as a delegate
+  id windowDelegate = [aWindow delegate];
+  if ([windowDelegate class] != [self class])
+    return;
+
+  nsCocoaWindow* geckoWidget = [windowDelegate geckoWidget];
+  NS_ASSERTION(geckoWidget, "Window delegate not returning a gecko widget!");
+  
+  nsMenuBarX* geckoMenuBar = geckoWidget->GetMenuBar();
+  if (geckoMenuBar) {
+    geckoMenuBar->Paint();
+  }
+  else {
+    // sometimes we don't have a native application menu early in launching
+    if (!sApplicationMenu)
+      return;
+
+    NSMenu* mainMenu = [NSApp mainMenu];
+    NS_ASSERTION([mainMenu numberOfItems] > 0, "Main menu does not have any items, something is terribly wrong!");
+
+    // Create a new menu bar.
+    // We create a GeckoNSMenu because all menu bar NSMenu objects should use that subclass for
+    // key handling reasons.
+    GeckoNSMenu* newMenuBar = [[GeckoNSMenu alloc] initWithTitle:@"MainMenuBar"];
+
+    // move the application menu from the existing menu bar to the new one
+    NSMenuItem* firstMenuItem = [[mainMenu itemAtIndex:0] retain];
+    [mainMenu removeItemAtIndex:0];
+    [newMenuBar insertItem:firstMenuItem atIndex:0];
+    [firstMenuItem release];
+
+    // set our new menu bar as the main menu
+    [NSApp setMainMenu:newMenuBar];
+    [newMenuBar release];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (id)initWithGeckoWindow:(nsCocoaWindow*)geckoWind
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  [super init];
+  mGeckoWindow = geckoWind;
+  mToplevelActiveState = false;
+  mHasEverBeenZoomed = false;
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (NSSize)windowWillResize:(NSWindow *)sender toSize:(NSSize)proposedFrameSize
+{
+  RollUpPopups();
+  
+  return proposedFrameSize;
+}
+
+- (void)windowDidResize:(NSNotification *)aNotification
+{
+  BaseWindow* window = [aNotification object];
+  [window updateTrackingArea];
+
+  if (!mGeckoWindow)
+    return;
+
+  // Resizing might have changed our zoom state.
+  mGeckoWindow->DispatchSizeModeEvent();
+  mGeckoWindow->ReportSizeEvent();
+}
+
+- (void)windowDidChangeScreen:(NSNotification *)aNotification
+{
+  if (!mGeckoWindow)
+    return;
+
+  // Because of Cocoa's peculiar treatment of zero-size windows (see comments
+  // at GetBackingScaleFactor() above), we sometimes have a situation where
+  // our concept of backing scale (based on the screen where the zero-sized
+  // window is positioned) differs from Cocoa's idea (always based on the
+  // Retina screen, AFAICT, even when an external non-Retina screen is the
+  // primary display).
+  //
+  // As a result, if the window was created with zero size on an external
+  // display, but then made visible on the (secondary) Retina screen, we
+  // will *not* get a windowDidChangeBackingProperties notification for it.
+  // This leads to an incorrect GetDefaultScale(), and widget coordinate
+  // confusion, as per bug 853252.
+  //
+  // To work around this, we check for a backing scale mismatch when we
+  // receive a windowDidChangeScreen notification, as we will receive this
+  // even if Cocoa was already treating the zero-size window as having
+  // Retina backing scale.
+  NSWindow *window = (NSWindow *)[aNotification object];
+  if ([window respondsToSelector:@selector(backingScaleFactor)]) {
+    if (GetBackingScaleFactor(window) != mGeckoWindow->BackingScaleFactor()) {
+      mGeckoWindow->BackingScaleFactorChanged();
+    }
+  }
+
+  mGeckoWindow->ReportMoveEvent();
+}
+
+// Lion's full screen mode will bypass our internal fullscreen tracking, so
+// we need to catch it when we transition and call our own methods, which in
+// turn will fire "fullscreen" events.
+- (void)windowDidEnterFullScreen:(NSNotification *)notification
+{
+  if (!mGeckoWindow) {
+    return;
+  }
+
+  mGeckoWindow->EnteredFullScreen(true);
+
+  // On Yosemite, the NSThemeFrame class has two new properties --
+  // titlebarView (an NSTitlebarView object) and titlebarContainerView (an
+  // NSTitlebarContainerView object).  These are used to display the titlebar
+  // in fullscreen mode.  In Safari they're not transparent.  But in Firefox
+  // for some reason they are, which causes bug 1069658.  The following code
+  // works around this Apple bug or design flaw.
+  NSWindow *window = (NSWindow *) [notification object];
+  NSView *frameView = [[window contentView] superview];
+  NSView *titlebarView = nil;
+  NSView *titlebarContainerView = nil;
+  if ([frameView respondsToSelector:@selector(titlebarView)]) {
+    titlebarView = [frameView titlebarView];
+  }
+  if ([frameView respondsToSelector:@selector(titlebarContainerView)]) {
+    titlebarContainerView = [frameView titlebarContainerView];
+  }
+  if ([titlebarView respondsToSelector:@selector(setTransparent:)]) {
+    [titlebarView setTransparent:NO];
+  }
+  if ([titlebarContainerView respondsToSelector:@selector(setTransparent:)]) {
+    [titlebarContainerView setTransparent:NO];
+  }
+}
+
+- (void)windowDidExitFullScreen:(NSNotification *)notification
+{
+  if (!mGeckoWindow) {
+    return;
+  }
+
+  mGeckoWindow->EnteredFullScreen(false);
+}
+
+- (void)windowDidFailToEnterFullScreen:(NSWindow *)window
+{
+  if (!mGeckoWindow) {
+    return;
+  }
+
+  mGeckoWindow->EnteredFullScreen(false);
+}
+
+- (void)windowDidFailToExitFullScreen:(NSWindow *)window
+{
+  if (!mGeckoWindow) {
+    return;
+  }
+
+  mGeckoWindow->EnteredFullScreen(true);
+}
+
+- (void)windowDidBecomeMain:(NSNotification *)aNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  RollUpPopups();
+  ChildViewMouseTracker::ReEvaluateMouseEnterState();
+
+  // [NSApp _isRunningAppModal] will return true if we're running an OS dialog
+  // app modally. If one of those is up then we want it to retain its menu bar.
+  if ([NSApp _isRunningAppModal])
+    return;
+  NSWindow* window = [aNotification object];
+  if (window)
+    [WindowDelegate paintMenubarForWindow:window];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)windowDidResignMain:(NSNotification *)aNotification
+{
+  RollUpPopups();
+  ChildViewMouseTracker::ReEvaluateMouseEnterState();
+
+  // [NSApp _isRunningAppModal] will return true if we're running an OS dialog
+  // app modally. If one of those is up then we want it to retain its menu bar.
+  if ([NSApp _isRunningAppModal])
+    return;
+  RefPtr<nsMenuBarX> hiddenWindowMenuBar = nsMenuUtilsX::GetHiddenWindowMenuBar();
+  if (hiddenWindowMenuBar) {
+    // printf("painting hidden window menu bar due to window losing main status\n");
+    hiddenWindowMenuBar->Paint();
+  }
+}
+
+- (void)windowDidBecomeKey:(NSNotification *)aNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  RollUpPopups();
+  ChildViewMouseTracker::ReEvaluateMouseEnterState();
+
+  NSWindow* window = [aNotification object];
+  if ([window isSheet])
+    [WindowDelegate paintMenubarForWindow:window];
+
+  nsChildView* mainChildView =
+    static_cast<nsChildView*>([[(BaseWindow*)window mainChildView] widget]);
+  if (mainChildView) {
+    if (mainChildView->GetInputContext().IsPasswordEditor()) {
+      TextInputHandler::EnableSecureEventInput();
+    } else {
+      TextInputHandler::EnsureSecureEventInputDisabled();
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)windowDidResignKey:(NSNotification *)aNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  RollUpPopups();
+  ChildViewMouseTracker::ReEvaluateMouseEnterState();
+
+  // If a sheet just resigned key then we should paint the menu bar
+  // for whatever window is now main.
+  NSWindow* window = [aNotification object];
+  if ([window isSheet])
+    [WindowDelegate paintMenubarForWindow:[NSApp mainWindow]];
+
+  TextInputHandler::EnsureSecureEventInputDisabled();
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)windowWillMove:(NSNotification *)aNotification
+{
+  RollUpPopups();
+}
+
+- (void)windowDidMove:(NSNotification *)aNotification
+{
+  if (mGeckoWindow)
+    mGeckoWindow->ReportMoveEvent();
+}
+
+- (BOOL)windowShouldClose:(id)sender
+{
+  nsIWidgetListener* listener = mGeckoWindow ? mGeckoWindow->GetWidgetListener() : nullptr;
+  if (listener)
+    listener->RequestWindowClose(mGeckoWindow);
+  return NO; // gecko will do it
+}
+
+- (void)windowWillClose:(NSNotification *)aNotification
+{
+  RollUpPopups();
+}
+
+- (void)windowWillMiniaturize:(NSNotification *)aNotification
+{
+  RollUpPopups();
+}
+
+- (void)windowDidMiniaturize:(NSNotification *)aNotification
+{
+  if (mGeckoWindow)
+    mGeckoWindow->DispatchSizeModeEvent();
+}
+
+- (void)windowDidDeminiaturize:(NSNotification *)aNotification
+{
+  if (mGeckoWindow)
+    mGeckoWindow->DispatchSizeModeEvent();
+}
+
+- (BOOL)windowShouldZoom:(NSWindow *)window toFrame:(NSRect)proposedFrame
+{
+  if (!mHasEverBeenZoomed && [window isZoomed])
+    return NO; // See bug 429954.
+
+  mHasEverBeenZoomed = YES;
+  return YES;
+}
+
+- (void)didEndSheet:(NSWindow*)sheet returnCode:(int)returnCode contextInfo:(void*)contextInfo
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Note: 'contextInfo' (if it is set) is the window that is the parent of
+  // the sheet.  The value of contextInfo is determined in
+  // nsCocoaWindow::Show().  If it's set, 'contextInfo' is always the top-
+  // level window, not another sheet itself.  But 'contextInfo' is nil if
+  // our parent window is also a sheet -- in that case we shouldn't send
+  // the top-level window any activate events (because it's our parent
+  // window that needs to get these events, not the top-level window).
+  [TopLevelWindowData deactivateInWindow:sheet];
+  [sheet orderOut:self];
+  if (contextInfo)
+    [TopLevelWindowData activateInWindow:(NSWindow*)contextInfo];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)windowDidChangeBackingProperties:(NSNotification *)aNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NSWindow *window = (NSWindow *)[aNotification object];
+
+  if ([window respondsToSelector:@selector(backingScaleFactor)]) {
+    CGFloat oldFactor =
+      [[[aNotification userInfo]
+         objectForKey:@"NSBackingPropertyOldScaleFactorKey"] doubleValue];
+    if ([window backingScaleFactor] != oldFactor) {
+      mGeckoWindow->BackingScaleFactorChanged();
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (nsCocoaWindow*)geckoWidget
+{
+  return mGeckoWindow;
+}
+
+- (bool)toplevelActiveState
+{
+  return mToplevelActiveState;
+}
+
+- (void)sendToplevelActivateEvents
+{
+  if (!mToplevelActiveState && mGeckoWindow) {
+    nsIWidgetListener* listener = mGeckoWindow->GetWidgetListener();
+    if (listener) {
+      listener->WindowActivated();
+    }
+    mToplevelActiveState = true;
+  }
+}
+
+- (void)sendToplevelDeactivateEvents
+{
+  if (mToplevelActiveState && mGeckoWindow) {
+    nsIWidgetListener* listener = mGeckoWindow->GetWidgetListener();
+    if (listener) {
+      listener->WindowDeactivated();
+    }
+    mToplevelActiveState = false;
+  }
+}
+
+@end
+
+static float
+GetDPI(NSWindow* aWindow)
+{
+  NSScreen* screen = [aWindow screen];
+  if (!screen)
+    return 96.0f;
+
+  CGDirectDisplayID displayID =
+    [[[screen deviceDescription] objectForKey:@"NSScreenNumber"] intValue];
+  CGFloat heightMM = ::CGDisplayScreenSize(displayID).height;
+  size_t heightPx = ::CGDisplayPixelsHigh(displayID);
+  if (heightMM < 1 || heightPx < 1) {
+    // Something extremely bogus is going on
+    return 96.0f;
+  }
+
+  float dpi = heightPx / (heightMM / MM_PER_INCH_FLOAT);
+
+  // Account for HiDPI mode where Cocoa's "points" do not correspond to real
+  // device pixels
+  CGFloat backingScale = GetBackingScaleFactor(aWindow);
+
+  return dpi * backingScale;
+}
+
+@interface NSView(FrameViewMethodSwizzling)
+- (NSPoint)FrameView__closeButtonOrigin;
+- (NSPoint)FrameView__fullScreenButtonOrigin;
+@end
+
+@implementation NSView(FrameViewMethodSwizzling)
+
+- (NSPoint)FrameView__closeButtonOrigin
+{
+  NSPoint defaultPosition = [self FrameView__closeButtonOrigin];
+  if ([[self window] isKindOfClass:[ToolbarWindow class]]) {
+    return [(ToolbarWindow*)[self window] windowButtonsPositionWithDefaultPosition:defaultPosition];
+  }
+  return defaultPosition;
+}
+
+- (NSPoint)FrameView__fullScreenButtonOrigin
+{
+  NSPoint defaultPosition = [self FrameView__fullScreenButtonOrigin];
+  if ([[self window] isKindOfClass:[ToolbarWindow class]]) {
+    return [(ToolbarWindow*)[self window] fullScreenButtonPositionWithDefaultPosition:defaultPosition];
+  }
+  return defaultPosition;
+}
+
+@end
+
+static NSMutableSet *gSwizzledFrameViewClasses = nil;
+
+@interface NSWindow(PrivateSetNeedsDisplayInRectMethod)
+ - (void)_setNeedsDisplayInRect:(NSRect)aRect;
+@end
+
+// This method is on NSThemeFrame starting with 10.10, but since NSThemeFrame
+// is not a public class, we declare the method on NSView instead. We only have
+// this declaration in order to avoid compiler warnings.
+@interface NSView(PrivateAddKnownSubviewMethod)
+ - (void)_addKnownSubview:(NSView*)aView positioned:(NSWindowOrderingMode)place relativeTo:(NSView*)otherView;
+@end
+
+#if !defined(MAC_OS_X_VERSION_10_10) || \
+    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_10
+
+@interface NSImage(CapInsets)
+- (void)setCapInsets:(NSEdgeInsets)capInsets;
+@end
+
+#endif
+
+#if !defined(MAC_OS_X_VERSION_10_8) || \
+    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_8
+
+@interface NSImage(ImageCreationWithDrawingHandler)
++ (NSImage *)imageWithSize:(NSSize)size
+                   flipped:(BOOL)drawingHandlerShouldBeCalledWithFlippedContext
+            drawingHandler:(BOOL (^)(NSRect dstRect))drawingHandler;
+@end
+
+#endif
+
+@interface NSView(NSVisualEffectViewSetMaskImage)
+- (void)setMaskImage:(NSImage*)image;
+@end
+
+@interface BaseWindow(Private)
+- (void)removeTrackingArea;
+- (void)cursorUpdated:(NSEvent*)aEvent;
+- (void)updateContentViewSize;
+- (void)reflowTitlebarElements;
+@end
+
+@implementation BaseWindow
+
+// The frame of a window is implemented using undocumented NSView subclasses.
+// We offset the window buttons by overriding the methods _closeButtonOrigin
+// and _fullScreenButtonOrigin on these frame view classes. The class which is
+// used for a window is determined in the window's frameViewClassForStyleMask:
+// method, so this is where we make sure that we have swizzled the method on
+// all encountered classes.
++ (Class)frameViewClassForStyleMask:(NSUInteger)styleMask
+{
+  Class frameViewClass = [super frameViewClassForStyleMask:styleMask];
+
+  if (!gSwizzledFrameViewClasses) {
+    gSwizzledFrameViewClasses = [[NSMutableSet setWithCapacity:3] retain];
+    if (!gSwizzledFrameViewClasses) {
+      return frameViewClass;
+    }
+  }
+
+  static IMP our_closeButtonOrigin =
+    class_getMethodImplementation([NSView class],
+                                  @selector(FrameView__closeButtonOrigin));
+  static IMP our_fullScreenButtonOrigin =
+    class_getMethodImplementation([NSView class],
+                                  @selector(FrameView__fullScreenButtonOrigin));
+
+  if (![gSwizzledFrameViewClasses containsObject:frameViewClass]) {
+    // Either of these methods might be implemented in both a subclass of
+    // NSFrameView and one of its own subclasses.  Which means that if we
+    // aren't careful we might end up swizzling the same method twice.
+    // Since method swizzling involves swapping pointers, this would break
+    // things.
+    IMP _closeButtonOrigin =
+      class_getMethodImplementation(frameViewClass,
+                                    @selector(_closeButtonOrigin));
+    if (_closeButtonOrigin && _closeButtonOrigin != our_closeButtonOrigin) {
+      nsToolkit::SwizzleMethods(frameViewClass, @selector(_closeButtonOrigin),
+                                @selector(FrameView__closeButtonOrigin));
+    }
+    IMP _fullScreenButtonOrigin =
+      class_getMethodImplementation(frameViewClass,
+                                    @selector(_fullScreenButtonOrigin));
+    if (_fullScreenButtonOrigin &&
+        _fullScreenButtonOrigin != our_fullScreenButtonOrigin) {
+      nsToolkit::SwizzleMethods(frameViewClass, @selector(_fullScreenButtonOrigin),
+                                @selector(FrameView__fullScreenButtonOrigin));
+    }
+    [gSwizzledFrameViewClasses addObject:frameViewClass];
+  }
+
+  return frameViewClass;
+}
+
+- (id)initWithContentRect:(NSRect)aContentRect styleMask:(NSUInteger)aStyle backing:(NSBackingStoreType)aBufferingType defer:(BOOL)aFlag
+{
+  mDrawsIntoWindowFrame = NO;
+  [super initWithContentRect:aContentRect styleMask:aStyle backing:aBufferingType defer:aFlag];
+  mState = nil;
+  mActiveTitlebarColor = nil;
+  mInactiveTitlebarColor = nil;
+  mScheduledShadowInvalidation = NO;
+  mDisabledNeedsDisplay = NO;
+  mDPI = GetDPI(self);
+  mTrackingArea = nil;
+  mDirtyRect = NSZeroRect;
+  mBeingShown = NO;
+  mDrawTitle = NO;
+  mBrightTitlebarForeground = NO;
+  mUseMenuStyle = NO;
+  [self updateTrackingArea];
+
+  return self;
+}
+
+// Returns an autoreleased NSImage.
+static NSImage*
+GetMenuMaskImage()
+{
+  CGFloat radius = 4.0f;
+  NSEdgeInsets insets = { 5, 5, 5, 5 };
+  NSSize maskSize = { 12, 12 };
+  NSImage* maskImage = [NSImage imageWithSize:maskSize flipped:YES drawingHandler:^BOOL(NSRect dstRect) {
+    NSBezierPath *path = [NSBezierPath bezierPathWithRoundedRect:dstRect xRadius:radius yRadius:radius];
+    [[NSColor colorWithDeviceWhite:1.0 alpha:1.0] set];
+    [path fill];
+    return YES;
+  }];
+  [maskImage setCapInsets:insets];
+  return maskImage;
+}
+
+- (void)swapOutChildViewWrapper:(NSView*)aNewWrapper
+{
+  [aNewWrapper setFrame:[[self contentView] frame]];
+  NSView* childView = [[self mainChildView] retain];
+  [childView removeFromSuperview];
+  [aNewWrapper addSubview:childView];
+  [childView release];
+  [super setContentView:aNewWrapper];
+}
+
+- (void)setUseMenuStyle:(BOOL)aValue
+{
+  if (!VibrancyManager::SystemSupportsVibrancy()) {
+    return;
+  }
+
+  if (aValue && !mUseMenuStyle) {
+    // Turn on rounded corner masking.
+    NSView* effectView = VibrancyManager::CreateEffectView(VibrancyType::MENU, YES);
+    if ([effectView respondsToSelector:@selector(setMaskImage:)]) {
+      [effectView setMaskImage:GetMenuMaskImage()];
+    }
+    [self swapOutChildViewWrapper:effectView];
+    [effectView release];
+  } else if (mUseMenuStyle && !aValue) {
+    // Turn off rounded corner masking.
+    NSView* wrapper = [[NSView alloc] initWithFrame:NSZeroRect];
+    [self swapOutChildViewWrapper:wrapper];
+    [wrapper release];
+  }
+  mUseMenuStyle = aValue;
+}
+
+- (void)setBeingShown:(BOOL)aValue
+{
+  mBeingShown = aValue;
+}
+
+- (BOOL)isBeingShown
+{
+  return mBeingShown;
+}
+
+- (BOOL)isVisibleOrBeingShown
+{
+  return [super isVisible] || mBeingShown;
+}
+
+- (void)disableSetNeedsDisplay
+{
+  mDisabledNeedsDisplay = YES;
+}
+
+- (void)enableSetNeedsDisplay
+{
+  mDisabledNeedsDisplay = NO;
+}
+
+- (void)dealloc
+{
+  [mActiveTitlebarColor release];
+  [mInactiveTitlebarColor release];
+  [self removeTrackingArea];
+  ChildViewMouseTracker::OnDestroyWindow(self);
+  [super dealloc];
+}
+
+static const NSString* kStateTitleKey = @"title";
+static const NSString* kStateDrawsContentsIntoWindowFrameKey = @"drawsContentsIntoWindowFrame";
+static const NSString* kStateActiveTitlebarColorKey = @"activeTitlebarColor";
+static const NSString* kStateInactiveTitlebarColorKey = @"inactiveTitlebarColor";
+static const NSString* kStateShowsToolbarButton = @"showsToolbarButton";
+static const NSString* kStateCollectionBehavior = @"collectionBehavior";
+
+- (void)importState:(NSDictionary*)aState
+{
+  [self setTitle:[aState objectForKey:kStateTitleKey]];
+  [self setDrawsContentsIntoWindowFrame:[[aState objectForKey:kStateDrawsContentsIntoWindowFrameKey] boolValue]];
+  [self setTitlebarColor:[aState objectForKey:kStateActiveTitlebarColorKey] forActiveWindow:YES];
+  [self setTitlebarColor:[aState objectForKey:kStateInactiveTitlebarColorKey] forActiveWindow:NO];
+  [self setShowsToolbarButton:[[aState objectForKey:kStateShowsToolbarButton] boolValue]];
+  [self setCollectionBehavior:[[aState objectForKey:kStateCollectionBehavior] unsignedIntValue]];
+}
+
+- (NSMutableDictionary*)exportState
+{
+  NSMutableDictionary* state = [NSMutableDictionary dictionaryWithCapacity:10];
+  [state setObject:[self title] forKey:kStateTitleKey];
+  [state setObject:[NSNumber numberWithBool:[self drawsContentsIntoWindowFrame]]
+            forKey:kStateDrawsContentsIntoWindowFrameKey];
+  NSColor* activeTitlebarColor = [self titlebarColorForActiveWindow:YES];
+  if (activeTitlebarColor) {
+    [state setObject:activeTitlebarColor forKey:kStateActiveTitlebarColorKey];
+  }
+  NSColor* inactiveTitlebarColor = [self titlebarColorForActiveWindow:NO];
+  if (inactiveTitlebarColor) {
+    [state setObject:inactiveTitlebarColor forKey:kStateInactiveTitlebarColorKey];
+  }
+  [state setObject:[NSNumber numberWithBool:[self showsToolbarButton]]
+            forKey:kStateShowsToolbarButton];
+  [state setObject:[NSNumber numberWithUnsignedInt: [self collectionBehavior]]
+            forKey:kStateCollectionBehavior];
+  return state;
+}
+
+- (void)setDrawsContentsIntoWindowFrame:(BOOL)aState
+{
+  bool changed = (aState != mDrawsIntoWindowFrame);
+  mDrawsIntoWindowFrame = aState;
+  if (changed) {
+    [self updateContentViewSize];
+    [self reflowTitlebarElements];
+  }
+}
+
+- (BOOL)drawsContentsIntoWindowFrame
+{
+  return mDrawsIntoWindowFrame;
+}
+
+- (void)setWantsTitleDrawn:(BOOL)aDrawTitle
+{
+  mDrawTitle = aDrawTitle;
+}
+
+- (BOOL)wantsTitleDrawn
+{
+  return mDrawTitle;
+}
+
+- (void)setUseBrightTitlebarForeground:(BOOL)aBrightForeground
+{
+  mBrightTitlebarForeground = aBrightForeground;
+  [[self standardWindowButton:NSWindowFullScreenButton] setNeedsDisplay:YES];
+}
+
+- (BOOL)useBrightTitlebarForeground
+{
+  return mBrightTitlebarForeground;
+}
+
+// Pass nil here to get the default appearance.
+- (void)setTitlebarColor:(NSColor*)aColor forActiveWindow:(BOOL)aActive
+{
+  [aColor retain];
+  if (aActive) {
+    [mActiveTitlebarColor release];
+    mActiveTitlebarColor = aColor;
+  } else {
+    [mInactiveTitlebarColor release];
+    mInactiveTitlebarColor = aColor;
+  }
+}
+
+- (NSColor*)titlebarColorForActiveWindow:(BOOL)aActive
+{
+  return aActive ? mActiveTitlebarColor : mInactiveTitlebarColor;
+}
+
+- (void)deferredInvalidateShadow
+{
+  if (mScheduledShadowInvalidation || [self isOpaque] || ![self hasShadow])
+    return;
+
+  [self performSelector:@selector(invalidateShadow) withObject:nil afterDelay:0];
+  mScheduledShadowInvalidation = YES;
+}
+
+- (void)invalidateShadow
+{
+  [super invalidateShadow];
+  mScheduledShadowInvalidation = NO;
+}
+
+- (float)getDPI
+{
+  return mDPI;
+}
+
+- (NSView*)trackingAreaView
+{
+  NSView* contentView = [self contentView];
+  return [contentView superview] ? [contentView superview] : contentView;
+}
+
+- (ChildView*)mainChildView
+{
+  NSView *contentView = [self contentView];
+  NSView* lastView = [[contentView subviews] lastObject];
+  if ([lastView isKindOfClass:[ChildView class]]) {
+    return (ChildView*)lastView;
+  }
+  return nil;
+}
+
+- (void)removeTrackingArea
+{
+  if (mTrackingArea) {
+    [[self trackingAreaView] removeTrackingArea:mTrackingArea];
+    [mTrackingArea release];
+    mTrackingArea = nil;
+  }
+}
+
+- (void)updateTrackingArea
+{
+  [self removeTrackingArea];
+
+  NSView* view = [self trackingAreaView];
+  const NSTrackingAreaOptions options =
+    NSTrackingMouseEnteredAndExited | NSTrackingMouseMoved | NSTrackingActiveAlways;
+  mTrackingArea = [[NSTrackingArea alloc] initWithRect:[view bounds]
+                                               options:options
+                                                 owner:self
+                                              userInfo:nil];
+  [view addTrackingArea:mTrackingArea];
+}
+
+- (void)mouseEntered:(NSEvent*)aEvent
+{
+  ChildViewMouseTracker::MouseEnteredWindow(aEvent);
+}
+
+- (void)mouseExited:(NSEvent*)aEvent
+{
+  ChildViewMouseTracker::MouseExitedWindow(aEvent);
+}
+
+- (void)mouseMoved:(NSEvent*)aEvent
+{
+  ChildViewMouseTracker::MouseMoved(aEvent);
+}
+
+- (void)cursorUpdated:(NSEvent*)aEvent
+{
+  // Nothing to do here, but NSTrackingArea wants us to implement this method.
+}
+
+- (void)_setNeedsDisplayInRect:(NSRect)aRect
+{
+  // Prevent unnecessary invalidations due to moving NSViews (e.g. for plugins)
+  if (!mDisabledNeedsDisplay) {
+    // This method is only called by Cocoa, so when we're here, we know that
+    // it's available and don't need to check whether our superclass responds
+    // to the selector.
+    [super _setNeedsDisplayInRect:aRect];
+    mDirtyRect = NSUnionRect(mDirtyRect, aRect);
+  }
+}
+
+- (NSRect)getAndResetNativeDirtyRect
+{
+  NSRect dirtyRect = mDirtyRect;
+  mDirtyRect = NSZeroRect;
+  return dirtyRect;
+}
+
+- (void)updateContentViewSize
+{
+  NSRect rect = [self contentRectForFrameRect:[self frame]];
+  [[self contentView] setFrameSize:rect.size];
+}
+
+// Possibly move the titlebar buttons.
+- (void)reflowTitlebarElements
+{
+  NSView *frameView = [[self contentView] superview];
+  if ([frameView respondsToSelector:@selector(_tileTitlebarAndRedisplay:)]) {
+    [frameView _tileTitlebarAndRedisplay:NO];
+  }
+}
+
+// Override methods that translate between content rect and frame rect.
+- (NSRect)contentRectForFrameRect:(NSRect)aRect
+{
+  if ([self drawsContentsIntoWindowFrame]) {
+    return aRect;
+  }
+  return [super contentRectForFrameRect:aRect];
+}
+
+- (NSRect)contentRectForFrameRect:(NSRect)aRect styleMask:(NSUInteger)aMask
+{
+  if ([self drawsContentsIntoWindowFrame]) {
+    return aRect;
+  }
+  if ([super respondsToSelector:@selector(contentRectForFrameRect:styleMask:)]) {
+    return [super contentRectForFrameRect:aRect styleMask:aMask];
+  } else {
+    return [NSWindow contentRectForFrameRect:aRect styleMask:aMask];
+  }
+}
+
+- (NSRect)frameRectForContentRect:(NSRect)aRect
+{
+  if ([self drawsContentsIntoWindowFrame]) {
+    return aRect;
+  }
+  return [super frameRectForContentRect:aRect];
+}
+
+- (NSRect)frameRectForContentRect:(NSRect)aRect styleMask:(NSUInteger)aMask
+{
+  if ([self drawsContentsIntoWindowFrame]) {
+    return aRect;
+  }
+  if ([super respondsToSelector:@selector(frameRectForContentRect:styleMask:)]) {
+    return [super frameRectForContentRect:aRect styleMask:aMask];
+  } else {
+    return [NSWindow frameRectForContentRect:aRect styleMask:aMask];
+  }
+}
+
+- (void)setContentView:(NSView*)aView
+{
+  [super setContentView:aView];
+
+  // Now move the contentView to the bottommost layer so that it's guaranteed
+  // to be under the window buttons.
+  NSView* frameView = [aView superview];
+  [aView removeFromSuperview];
+  if ([frameView respondsToSelector:@selector(_addKnownSubview:positioned:relativeTo:)]) {
+    // 10.10 prints a warning when we call addSubview on the frame view, so we
+    // silence the warning by calling a private method instead.
+    [frameView _addKnownSubview:aView positioned:NSWindowBelow relativeTo:nil];
+  } else {
+    [frameView addSubview:aView positioned:NSWindowBelow relativeTo:nil];
+  }
+}
+
+- (NSArray*)titlebarControls
+{
+  // Return all subviews of the frameView which are not the content view.
+  NSView* frameView = [[self contentView] superview];
+  NSMutableArray* array = [[[frameView subviews] mutableCopy] autorelease];
+  [array removeObject:[self contentView]];
+  return array;
+}
+
+- (BOOL)respondsToSelector:(SEL)aSelector
+{
+  // Claim the window doesn't respond to this so that the system
+  // doesn't steal keyboard equivalents for it. Bug 613710.
+  if (aSelector == @selector(cancelOperation:)) {
+    return NO;
+  }
+
+  return [super respondsToSelector:aSelector];
+}
+
+- (void) doCommandBySelector:(SEL)aSelector
+{
+  // We override this so that it won't beep if it can't act.
+  // We want to control the beeping for missing or disabled
+  // commands ourselves.
+  [self tryToPerform:aSelector with:nil];
+}
+
+- (id)accessibilityAttributeValue:(NSString *)attribute
+{
+  id retval = [super accessibilityAttributeValue:attribute];
+
+  // The following works around a problem with Text-to-Speech on OS X 10.7.
+  // See bug 674612 for more info.
+  //
+  // When accessibility is off, AXUIElementCopyAttributeValue(), when called
+  // on an AXApplication object to get its AXFocusedUIElement attribute,
+  // always returns an AXWindow object (the actual browser window -- never a
+  // mozAccessible object).  This also happens with accessibility turned on,
+  // if no other object in the browser window has yet been focused.  But if
+  // the browser window has a title bar (as it currently always does), the
+  // AXWindow object will always have four "accessible" children, one of which
+  // is an AXStaticText object (the title bar's "title"; the other three are
+  // the close, minimize and zoom buttons).  This means that (for complicated
+  // reasons, for which see bug 674612) Text-to-Speech on OS X 10.7 will often
+  // "speak" the window title, no matter what text is selected, or even if no
+  // text at all is selected.  (This always happens when accessibility is off.
+  // It doesn't happen in Firefox releases because Apple has (on OS X 10.7)
+  // special-cased the handling of apps whose CFBundleIdentifier is
+  // org.mozilla.firefox.)
+  //
+  // We work around this problem by only returning AXChildren that are
+  // mozAccessible object or are one of the titlebar's buttons (which
+  // instantiate subclasses of NSButtonCell).
+  if ([retval isKindOfClass:[NSArray class]] &&
+      [attribute isEqualToString:@"AXChildren"]) {
+    NSMutableArray *holder = [NSMutableArray arrayWithCapacity:10];
+    [holder addObjectsFromArray:(NSArray *)retval];
+    NSUInteger count = [holder count];
+    for (NSInteger i = count - 1; i >= 0; --i) {
+      id item = [holder objectAtIndex:i];
+      // Remove anything from holder that isn't one of the titlebar's buttons
+      // (which instantiate subclasses of NSButtonCell) or a mozAccessible
+      // object (or one of its subclasses).
+      if (![item isKindOfClass:[NSButtonCell class]] &&
+          ![item respondsToSelector:@selector(hasRepresentedView)]) {
+        [holder removeObjectAtIndex:i];
+      }
+    }
+    retval = [NSArray arrayWithArray:holder];
+  }
+
+  return retval;
+}
+
+@end
+
+// This class allows us to exercise control over the window's title bar. This
+// allows for a "unified toolbar" look without having to extend the content
+// area into the title bar. It works like this:
+// 1) We set the window's style to textured.
+// 2) Because of this, the background color applies to the entire window, including
+//     the titlebar area. For normal textured windows, the default pattern is a 
+//    "brushed metal" image on Tiger and a unified gradient on Leopard.
+// 3) We set the background color to a custom NSColor subclass that knows how tall the window is.
+//    When -set is called on it, it sets a pattern (with a draw callback) as the fill. In that callback,
+//    it paints the the titlebar and background colors in the correct areas of the context it's given,
+//    which will fill the entire window (CG will tile it horizontally for us).
+// 4) Whenever the window's main state changes and when [window display] is called,
+//    Cocoa redraws the titlebar using the patternDraw callback function.
+//
+// This class also provides us with a pill button to show/hide the toolbar up to 10.6.
+//
+// Drawing the unified gradient in the titlebar and the toolbar works like this:
+// 1) In the style sheet we set the toolbar's -moz-appearance to toolbar.
+// 2) When the toolbar is visible and we paint the application chrome
+//    window, the array that Gecko passes nsChildView::UpdateThemeGeometries
+//    will contain an entry for the widget type NS_THEME_TOOLBAR.
+// 3) nsChildView::UpdateThemeGeometries finds the toolbar frame's ToolbarWindow
+//    and passes the toolbar frame's height to setUnifiedToolbarHeight.
+// 4) If the toolbar height has changed, a titlebar redraw is triggered and the
+//    upper part of the unified gradient is drawn in the titlebar.
+// 5) The lower part of the unified gradient in the toolbar is drawn during
+//    normal window content painting in nsNativeThemeCocoa::DrawUnifiedToolbar.
+//
+// Whenever the unified gradient is drawn in the titlebar or the toolbar, both
+// titlebar height and toolbar height must be known in order to construct the
+// correct gradient. But you can only get from the toolbar frame
+// to the containing window - the other direction doesn't work. That's why the
+// toolbar height is cached in the ToolbarWindow but nsNativeThemeCocoa can simply
+// query the window for its titlebar height when drawing the toolbar.
+//
+// Note that in drawsContentsIntoWindowFrame mode, titlebar drawing works in a
+// completely different way: In that mode, the window's mainChildView will
+// cover the titlebar completely and nothing that happens in the window
+// background will reach the screen.
+@implementation ToolbarWindow
+
+- (id)initWithContentRect:(NSRect)aContentRect styleMask:(NSUInteger)aStyle backing:(NSBackingStoreType)aBufferingType defer:(BOOL)aFlag
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  aStyle = aStyle | NSTexturedBackgroundWindowMask;
+  if ((self = [super initWithContentRect:aContentRect styleMask:aStyle backing:aBufferingType defer:aFlag])) {
+    mColor = [[TitlebarAndBackgroundColor alloc] initWithWindow:self];
+    // Bypass our guard method below.
+    [super setBackgroundColor:mColor];
+    mBackgroundColor = [[NSColor whiteColor] retain];
+
+    mUnifiedToolbarHeight = 22.0f;
+    mWindowButtonsRect = NSZeroRect;
+    mFullScreenButtonRect = NSZeroRect;
+
+    // setBottomCornerRounded: is a private API call, so we check to make sure
+    // we respond to it just in case.
+    if ([self respondsToSelector:@selector(setBottomCornerRounded:)])
+      [self setBottomCornerRounded:YES];
+
+    [self setAutorecalculatesContentBorderThickness:NO forEdge:NSMaxYEdge];
+    [self setContentBorderThickness:0.0f forEdge:NSMaxYEdge];
+  }
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [super setBackgroundColor:[NSColor whiteColor]];
+  [mColor release];
+  [mBackgroundColor release];
+  [mTitlebarView release];
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)setTitlebarColor:(NSColor*)aColor forActiveWindow:(BOOL)aActive
+{
+  [super setTitlebarColor:aColor forActiveWindow:aActive];
+  [self setTitlebarNeedsDisplayInRect:[self titlebarRect]];
+}
+
+- (void)setBackgroundColor:(NSColor*)aColor
+{
+  [aColor retain];
+  [mBackgroundColor release];
+  mBackgroundColor = aColor;
+}
+
+- (NSColor*)windowBackgroundColor
+{
+  return mBackgroundColor;
+}
+
+- (void)setTemporaryBackgroundColor
+{
+  [super setBackgroundColor:[NSColor whiteColor]];
+}
+
+- (void)restoreBackgroundColor
+{
+  [super setBackgroundColor:mBackgroundColor];
+}
+
+- (void)setTitlebarNeedsDisplayInRect:(NSRect)aRect
+{
+  [self setTitlebarNeedsDisplayInRect:aRect sync:NO];
+}
+
+- (void)setTitlebarNeedsDisplayInRect:(NSRect)aRect sync:(BOOL)aSync
+{
+  NSRect titlebarRect = [self titlebarRect];
+  NSRect rect = NSIntersectionRect(titlebarRect, aRect);
+  if (NSIsEmptyRect(rect))
+    return;
+
+  NSView* borderView = [[self contentView] superview];
+  if (!borderView)
+    return;
+
+  if (aSync) {
+    [borderView displayRect:rect];
+  } else {
+    [borderView setNeedsDisplayInRect:rect];
+  }
+}
+
+- (NSRect)titlebarRect
+{
+  CGFloat titlebarHeight = [self titlebarHeight];
+  return NSMakeRect(0, [self frame].size.height - titlebarHeight,
+                    [self frame].size.width, titlebarHeight);
+}
+
+// Returns the unified height of titlebar + toolbar.
+- (CGFloat)unifiedToolbarHeight
+{
+  return mUnifiedToolbarHeight;
+}
+
+- (CGFloat)titlebarHeight
+{
+  // We use the original content rect here, not what we return from
+  // [self contentRectForFrameRect:], because that would give us a
+  // titlebarHeight of zero in drawsContentsIntoWindowFrame mode.
+  NSRect frameRect = [self frame];
+  NSRect originalContentRect = [NSWindow contentRectForFrameRect:frameRect styleMask:[self styleMask]];
+  return NSMaxY(frameRect) - NSMaxY(originalContentRect);
+}
+
+// Stores the complete height of titlebar + toolbar.
+- (void)setUnifiedToolbarHeight:(CGFloat)aHeight
+{
+  if (aHeight == mUnifiedToolbarHeight)
+    return;
+
+  mUnifiedToolbarHeight = aHeight;
+
+  if (![self drawsContentsIntoWindowFrame]) {
+    // Redraw the title bar. If we're inside painting, we'll do it right now,
+    // otherwise we'll just invalidate it.
+    BOOL needSyncRedraw = ([NSView focusView] != nil);
+    [self setTitlebarNeedsDisplayInRect:[self titlebarRect] sync:needSyncRedraw];
+  }
+}
+
+// Extending the content area into the title bar works by resizing the
+// mainChildView so that it covers the titlebar.
+- (void)setDrawsContentsIntoWindowFrame:(BOOL)aState
+{
+  BOOL stateChanged = ([self drawsContentsIntoWindowFrame] != aState);
+  [super setDrawsContentsIntoWindowFrame:aState];
+  if (stateChanged && [[self delegate] isKindOfClass:[WindowDelegate class]]) {
+    // Here we extend / shrink our mainChildView. We do that by firing a resize
+    // event which will cause the ChildView to be resized to the rect returned
+    // by nsCocoaWindow::GetClientBounds. GetClientBounds bases its return
+    // value on what we return from drawsContentsIntoWindowFrame.
+    WindowDelegate *windowDelegate = (WindowDelegate *)[self delegate];
+    nsCocoaWindow *geckoWindow = [windowDelegate geckoWidget];
+    if (geckoWindow) {
+      // Re-layout our contents.
+      geckoWindow->ReportSizeEvent();
+    }
+
+    // Resizing the content area causes a reflow which would send a synthesized
+    // mousemove event to the old mouse position relative to the top left
+    // corner of the content area. But the mouse has shifted relative to the
+    // content area, so that event would have wrong position information. So
+    // we'll send a mouse move event with the correct new position.
+    ChildViewMouseTracker::ResendLastMouseMoveEvent();
+  }
+}
+
+- (void)setWantsTitleDrawn:(BOOL)aDrawTitle
+{
+  [super setWantsTitleDrawn:aDrawTitle];
+  [self setTitlebarNeedsDisplayInRect:[self titlebarRect]];
+}
+
+- (void)setSheetAttachmentPosition:(CGFloat)aY
+{
+  CGFloat topMargin = aY - [self titlebarHeight];
+  [self setContentBorderThickness:topMargin forEdge:NSMaxYEdge];
+}
+
+- (void)placeWindowButtons:(NSRect)aRect
+{
+  if (!NSEqualRects(mWindowButtonsRect, aRect)) {
+    mWindowButtonsRect = aRect;
+    [self reflowTitlebarElements];
+  }
+}
+
+- (NSPoint)windowButtonsPositionWithDefaultPosition:(NSPoint)aDefaultPosition
+{
+  NSInteger styleMask = [self styleMask];
+  if ([self drawsContentsIntoWindowFrame] &&
+      !(styleMask & NSFullScreenWindowMask) && (styleMask & NSTitledWindowMask)) {
+    if (NSIsEmptyRect(mWindowButtonsRect)) {
+      // Empty rect. Let's hide the buttons.
+      // Position is in non-flipped window coordinates. Using frame's height
+      // for the vertical coordinate will move the buttons above the window,
+      // making them invisible.
+      return NSMakePoint(0, [self frame].size.height);
+    }
+    return NSMakePoint(mWindowButtonsRect.origin.x, mWindowButtonsRect.origin.y);
+  }
+  return aDefaultPosition;
+}
+
+- (void)placeFullScreenButton:(NSRect)aRect
+{
+  if (!NSEqualRects(mFullScreenButtonRect, aRect)) {
+    mFullScreenButtonRect = aRect;
+    [self reflowTitlebarElements];
+  }
+}
+
+- (NSPoint)fullScreenButtonPositionWithDefaultPosition:(NSPoint)aDefaultPosition
+{
+  if ([self drawsContentsIntoWindowFrame] && !NSIsEmptyRect(mFullScreenButtonRect)) {
+    return NSMakePoint(std::min(mFullScreenButtonRect.origin.x, aDefaultPosition.x),
+                       std::min(mFullScreenButtonRect.origin.y, aDefaultPosition.y));
+  }
+  return aDefaultPosition;
+}
+
+// Returning YES here makes the setShowsToolbarButton method work even though
+// the window doesn't contain an NSToolbar.
+- (BOOL)_hasToolbar
+{
+  return YES;
+}
+
+// Dispatch a toolbar pill button clicked message to Gecko.
+- (void)_toolbarPillButtonClicked:(id)sender
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  RollUpPopups();
+
+  if ([[self delegate] isKindOfClass:[WindowDelegate class]]) {
+    WindowDelegate *windowDelegate = (WindowDelegate *)[self delegate];
+    nsCocoaWindow *geckoWindow = [windowDelegate geckoWidget];
+    if (!geckoWindow)
+      return;
+
+    nsIWidgetListener* listener = geckoWindow->GetWidgetListener();
+    if (listener)
+      listener->OSToolbarButtonPressed();
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Retain and release "self" to avoid crashes when our widget (and its native
+// window) is closed as a result of processing a key equivalent (e.g.
+// Command+w or Command+q).  This workaround is only needed for a window
+// that can become key.
+- (BOOL)performKeyEquivalent:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NSWindow *nativeWindow = [self retain];
+  BOOL retval = [super performKeyEquivalent:theEvent];
+  [nativeWindow release];
+  return retval;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+- (void)sendEvent:(NSEvent *)anEvent
+{
+  NSEventType type = [anEvent type];
+  
+  switch (type) {
+    case NSScrollWheel:
+    case NSLeftMouseDown:
+    case NSLeftMouseUp:
+    case NSRightMouseDown:
+    case NSRightMouseUp:
+    case NSOtherMouseDown:
+    case NSOtherMouseUp:
+    case NSMouseMoved:
+    case NSLeftMouseDragged:
+    case NSRightMouseDragged:
+    case NSOtherMouseDragged:
+    {
+      // Drop all mouse events if a modal window has appeared above us.
+      // This helps make us behave as if the OS were running a "real" modal
+      // event loop.
+      id delegate = [self delegate];
+      if (delegate && [delegate isKindOfClass:[WindowDelegate class]]) {
+        nsCocoaWindow *widget = [(WindowDelegate *)delegate geckoWidget];
+        if (widget) {
+          if (gGeckoAppModalWindowList && (widget != gGeckoAppModalWindowList->window))
+            return;
+          if (widget->HasModalDescendents())
+            return;
+        }
+      }
+      break;
+    }
+    default:
+      break;
+  }
+
+  [super sendEvent:anEvent];
+}
+
+@end
+
+// Custom NSColor subclass where most of the work takes place for drawing in
+// the titlebar area. Not used in drawsContentsIntoWindowFrame mode.
+@implementation TitlebarAndBackgroundColor
+
+- (id)initWithWindow:(ToolbarWindow*)aWindow
+{
+  if ((self = [super init])) {
+    mWindow = aWindow; // weak ref to avoid a cycle
+  }
+  return self;
+}
+
+static void
+DrawNativeTitlebar(CGContextRef aContext, CGRect aTitlebarRect,
+                   CGFloat aUnifiedToolbarHeight, BOOL aIsMain)
+{
+  nsNativeThemeCocoa::DrawNativeTitlebar(aContext, aTitlebarRect, aUnifiedToolbarHeight, aIsMain, NO);
+
+  // The call to CUIDraw doesn't draw the top pixel strip at some window widths.
+  // We don't want to have a flickering transparent line, so we overdraw it.
+  CGContextSetRGBFillColor(aContext, 0.95, 0.95, 0.95, 1);
+  CGContextFillRect(aContext, CGRectMake(0, CGRectGetMaxY(aTitlebarRect) - 1,
+                                           aTitlebarRect.size.width, 1));
+}
+
+// Pattern draw callback for standard titlebar gradients and solid titlebar colors
+static void
+TitlebarDrawCallback(void* aInfo, CGContextRef aContext)
+{
+  ToolbarWindow *window = (ToolbarWindow*)aInfo;
+  if (![window drawsContentsIntoWindowFrame]) {
+    NSRect titlebarRect = [window titlebarRect];
+    BOOL isMain = [window isMainWindow];
+    NSColor *titlebarColor = [window titlebarColorForActiveWindow:isMain];
+    if (!titlebarColor) {
+      // If the titlebar color is nil, draw the default titlebar shading.
+      DrawNativeTitlebar(aContext, NSRectToCGRect(titlebarRect),
+                         [window unifiedToolbarHeight], isMain);
+    } else {
+      // If the titlebar color is not nil, just set and draw it normally.
+      [NSGraphicsContext saveGraphicsState];
+      [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:aContext flipped:NO]];
+      [titlebarColor set];
+      NSRectFill(titlebarRect);
+      [NSGraphicsContext restoreGraphicsState];
+    }
+  }
+}
+
+- (void)setFill
+{
+  float patternWidth = [mWindow frame].size.width;
+
+  CGPatternCallbacks callbacks = {0, &TitlebarDrawCallback, NULL};
+  CGPatternRef pattern = CGPatternCreate(mWindow, CGRectMake(0.0f, 0.0f, patternWidth, [mWindow frame].size.height), 
+                                         CGAffineTransformIdentity, patternWidth, [mWindow frame].size.height,
+                                         kCGPatternTilingConstantSpacing, true, &callbacks);
+
+  // Set the pattern as the fill, which is what we were asked to do. All our
+  // drawing will take place in the patternDraw callback.
+  CGColorSpaceRef patternSpace = CGColorSpaceCreatePattern(NULL);
+  CGContextRef context = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
+  CGContextSetFillColorSpace(context, patternSpace);
+  CGColorSpaceRelease(patternSpace);
+  CGFloat component = 1.0f;
+  CGContextSetFillPattern(context, pattern, &component);
+  CGPatternRelease(pattern);
+}
+
+- (void)set
+{
+  [self setFill];
+}
+
+- (NSString*)colorSpaceName
+{
+  return NSDeviceRGBColorSpace;
+}
+
+@end
+
+@implementation PopupWindow
+
+- (id)initWithContentRect:(NSRect)contentRect styleMask:(NSUInteger)styleMask
+      backing:(NSBackingStoreType)bufferingType defer:(BOOL)deferCreation
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  mIsContextMenu = false;
+  return [super initWithContentRect:contentRect styleMask:styleMask
+          backing:bufferingType defer:deferCreation];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (BOOL)isContextMenu
+{
+  return mIsContextMenu;
+}
+
+- (void)setIsContextMenu:(BOOL)flag
+{
+  mIsContextMenu = flag;
+}
+
+- (BOOL)canBecomeMainWindow
+{
+  // This is overriden because the default is 'yes' when a titlebar is present.
+  return NO;
+}
+
+@end
+
+// According to Apple's docs on [NSWindow canBecomeKeyWindow] and [NSWindow
+// canBecomeMainWindow], windows without a title bar or resize bar can't (by
+// default) become key or main.  But if a window can't become key, it can't
+// accept keyboard input (bmo bug 393250).  And it should also be possible for
+// an otherwise "ordinary" window to become main.  We need to override these
+// two methods to make this happen.
+@implementation BorderlessWindow
+
+- (BOOL)canBecomeKeyWindow
+{
+  return YES;
+}
+
+- (void)sendEvent:(NSEvent *)anEvent
+{
+  NSEventType type = [anEvent type];
+  
+  switch (type) {
+    case NSScrollWheel:
+    case NSLeftMouseDown:
+    case NSLeftMouseUp:
+    case NSRightMouseDown:
+    case NSRightMouseUp:
+    case NSOtherMouseDown:
+    case NSOtherMouseUp:
+    case NSMouseMoved:
+    case NSLeftMouseDragged:
+    case NSRightMouseDragged:
+    case NSOtherMouseDragged:
+    {
+      // Drop all mouse events if a modal window has appeared above us.
+      // This helps make us behave as if the OS were running a "real" modal
+      // event loop.
+      id delegate = [self delegate];
+      if (delegate && [delegate isKindOfClass:[WindowDelegate class]]) {
+        nsCocoaWindow *widget = [(WindowDelegate *)delegate geckoWidget];
+        if (widget) {
+          if (gGeckoAppModalWindowList && (widget != gGeckoAppModalWindowList->window))
+            return;
+          if (widget->HasModalDescendents())
+            return;
+        }
+      }
+      break;
+    }
+    default:
+      break;
+  }
+
+  [super sendEvent:anEvent];
+}
+
+// Apple's doc on this method says that the NSWindow class's default is not to
+// become main if the window isn't "visible" -- so we should replicate that
+// behavior here.  As best I can tell, the [NSWindow isVisible] method is an
+// accurate test of what Apple means by "visibility".
+- (BOOL)canBecomeMainWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (![self isVisible])
+    return NO;
+  return YES;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+// Retain and release "self" to avoid crashes when our widget (and its native
+// window) is closed as a result of processing a key equivalent (e.g.
+// Command+w or Command+q).  This workaround is only needed for a window
+// that can become key.
+- (BOOL)performKeyEquivalent:(NSEvent*)theEvent
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  NSWindow *nativeWindow = [self retain];
+  BOOL retval = [super performKeyEquivalent:theEvent];
+  [nativeWindow release];
+  return retval;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+@end
diff --git a/widget/cocoa/nsColorPicker.h b/widget/cocoa/nsColorPicker.h
new file mode 100644
index 0000000000..4b3e262188
--- /dev/null
+++ b/widget/cocoa/nsColorPicker.h
@@ -0,0 +1,50 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsColorPicker_h_
+#define nsColorPicker_h_
+
+#include "nsIColorPicker.h"
+#include "nsString.h"
+#include "nsCOMPtr.h"
+
+class nsIColorPickerShownCallback;
+class mozIDOMWindowProxy;
+@class NSColorPanelWrapper;
+@class NSColor;
+
+class nsColorPicker final : public nsIColorPicker
+{
+public:
+  NS_DECL_ISUPPORTS
+
+  NS_IMETHOD Init(mozIDOMWindowProxy* aParent, const nsAString& aTitle,
+                  const nsAString& aInitialColor) override;
+  NS_IMETHOD Open(nsIColorPickerShownCallback* aCallback) override;
+
+  // For NSColorPanelWrapper.
+  void Update(NSColor* aColor);
+  // Call this method if you are done with this input, but the color picker needs to
+  // stay open as it will be associated to another input
+  void DoneWithRetarget();
+  // Same as DoneWithRetarget + clean the static instance of sColorPanelWrapper,
+  // as it is not needed anymore for now
+  void Done();
+
+private:
+  ~nsColorPicker();
+
+  static NSColor* GetNSColorFromHexString(const nsAString& aColor);
+  static void GetHexStringFromNSColor(NSColor* aColor, nsAString& aResult);
+
+  static NSColorPanelWrapper* sColorPanelWrapper;
+
+  nsString             mTitle;
+  nsString             mColor;
+  nsCOMPtr<nsIColorPickerShownCallback> mCallback;
+};
+
+#endif // nsColorPicker_h_
diff --git a/widget/cocoa/nsColorPicker.mm b/widget/cocoa/nsColorPicker.mm
new file mode 100644
index 0000000000..263ea349b0
--- /dev/null
+++ b/widget/cocoa/nsColorPicker.mm
@@ -0,0 +1,188 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsColorPicker.h"
+#include "nsCocoaUtils.h"
+#include "nsThreadUtils.h"
+
+using namespace mozilla;
+
+static unsigned int
+HexStrToInt(NSString* str)
+{
+  unsigned int result = 0;
+
+  for (unsigned int i = 0; i < [str length]; ++i) {
+    char c = [str characterAtIndex:i];
+    result *= 16;
+    if (c >= '0' && c <= '9') {
+      result += c - '0';
+    } else if (c >= 'A' && c <= 'F') {
+      result += 10 + (c - 'A');
+    } else {
+      result += 10 + (c - 'a');
+    }
+  }
+
+  return result;
+}
+
+@interface NSColorPanelWrapper : NSObject <NSWindowDelegate>
+{
+  NSColorPanel*  mColorPanel;
+  nsColorPicker* mColorPicker;
+}
+- (id)initWithPicker:(nsColorPicker*)aPicker;
+- (void)open:(NSColor*)aInitialColor title:(NSString*)aTitle;
+- (void)retarget:(nsColorPicker*)aPicker;
+- (void)colorChanged:(NSColorPanel*)aPanel;
+@end
+
+@implementation NSColorPanelWrapper
+- (id)initWithPicker:(nsColorPicker*)aPicker
+{
+  mColorPicker = aPicker;
+  mColorPanel = [NSColorPanel sharedColorPanel];
+
+  self = [super init];
+  return self;
+}
+
+- (void)open:(NSColor*)aInitialColor title:(NSString*)aTitle
+{
+  [mColorPanel setTarget:self];
+  [mColorPanel setAction:@selector(colorChanged:)];
+  [mColorPanel setDelegate:self];
+  [mColorPanel setTitle:aTitle];
+  [mColorPanel setColor:aInitialColor];
+  [mColorPanel makeKeyAndOrderFront:nil];
+}
+
+- (void)colorChanged:(NSColorPanel*)aPanel
+{
+  mColorPicker->Update([mColorPanel color]);
+}
+
+- (void)windowWillClose:(NSNotification*)aNotification
+{
+  mColorPicker->Done();
+}
+
+- (void)retarget:(nsColorPicker*)aPicker
+{
+  mColorPicker->DoneWithRetarget();
+  mColorPicker = aPicker;
+}
+
+- (void)dealloc
+{
+  [mColorPanel setTarget:nil];
+  [mColorPanel setAction:nil];
+  [mColorPanel setDelegate:nil];
+
+  mColorPanel = nil;
+  mColorPicker = nullptr;
+
+  [super dealloc];
+}
+@end
+
+NS_IMPL_ISUPPORTS(nsColorPicker, nsIColorPicker)
+
+NSColorPanelWrapper* nsColorPicker::sColorPanelWrapper = nullptr;
+
+nsColorPicker::~nsColorPicker()
+{
+}
+
+NS_IMETHODIMP
+nsColorPicker::Init(mozIDOMWindowProxy* aParent, const nsAString& aTitle,
+                    const nsAString& aInitialColor)
+{
+  MOZ_ASSERT(NS_IsMainThread(),
+      "Color pickers can only be opened from main thread currently");
+  mTitle = aTitle;
+  mColor = aInitialColor;
+
+  if (sColorPanelWrapper) {
+    // Update current wrapper to target the new input instead
+    [sColorPanelWrapper retarget:this];
+  } else {
+    // Create a brand new color panel wrapper
+    sColorPanelWrapper = [[NSColorPanelWrapper alloc] initWithPicker:this];
+  }
+  return NS_OK;
+}
+
+/* static */ NSColor*
+nsColorPicker::GetNSColorFromHexString(const nsAString& aColor)
+{
+  NSString* str = nsCocoaUtils::ToNSString(aColor);
+
+  double red = HexStrToInt([str substringWithRange:NSMakeRange(1, 2)]) / 255.0;
+  double green = HexStrToInt([str substringWithRange:NSMakeRange(3, 2)]) / 255.0;
+  double blue = HexStrToInt([str substringWithRange:NSMakeRange(5, 2)]) / 255.0;
+
+  return [NSColor colorWithDeviceRed: red green: green blue: blue alpha: 1.0];
+}
+
+/* static */ void
+nsColorPicker::GetHexStringFromNSColor(NSColor* aColor, nsAString& aResult)
+{
+  CGFloat redFloat, greenFloat, blueFloat;
+
+  NSColor* color = aColor;
+  @try {
+    [color getRed:&redFloat green:&greenFloat blue:&blueFloat alpha: nil];
+  } @catch (NSException* e) {
+    color = [color colorUsingColorSpace:[NSColorSpace genericRGBColorSpace]];
+    [color getRed:&redFloat green:&greenFloat blue:&blueFloat alpha: nil];
+  }
+
+  nsCocoaUtils::GetStringForNSString([NSString stringWithFormat:@"#%02x%02x%02x",
+                                       (int)(redFloat * 255),
+                                       (int)(greenFloat * 255),
+                                       (int)(blueFloat * 255)],
+                                     aResult);
+}
+
+NS_IMETHODIMP
+nsColorPicker::Open(nsIColorPickerShownCallback* aCallback)
+{
+  MOZ_ASSERT(aCallback);
+  mCallback = aCallback;
+
+  [sColorPanelWrapper open:GetNSColorFromHexString(mColor)
+              title:nsCocoaUtils::ToNSString(mTitle)];
+
+  NS_ADDREF_THIS();
+
+  return NS_OK;
+}
+
+void
+nsColorPicker::Update(NSColor* aColor)
+{
+  GetHexStringFromNSColor(aColor, mColor);
+  mCallback->Update(mColor);
+}
+
+void
+nsColorPicker::DoneWithRetarget()
+{
+  mCallback->Done(EmptyString());
+  mCallback = nullptr;
+  NS_RELEASE_THIS();
+}
+
+void
+nsColorPicker::Done()
+{
+  [sColorPanelWrapper release];
+  sColorPanelWrapper = nullptr;
+  DoneWithRetarget();
+}
diff --git a/widget/cocoa/nsCursorManager.h b/widget/cocoa/nsCursorManager.h
new file mode 100644
index 0000000000..6dba8f9034
--- /dev/null
+++ b/widget/cocoa/nsCursorManager.h
@@ -0,0 +1,65 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsCursorManager_h_
+#define nsCursorManager_h_
+
+#import <Foundation/Foundation.h>
+#include "nsIWidget.h"
+#include "nsMacCursor.h"
+
+/*! @class      nsCursorManager
+    @abstract   Singleton service provides access to all cursors available in the application.
+    @discussion Use <code>nsCusorManager</code> to set the current cursor using an XP <code>nsCusor</code> enum value.
+                <code>nsCursorManager</code> encapsulates the details of setting different types of cursors, animating
+                cursors and cleaning up cursors when they are no longer in use.
+ */
+@interface nsCursorManager : NSObject
+{
+  @private
+  NSMutableDictionary *mCursors;
+  nsMacCursor *mCurrentMacCursor;
+}
+
+/*! @method     setCursor:
+    @abstract   Sets the current cursor.
+    @discussion Sets the current cursor to the cursor indicated by the XP cursor constant given as an argument.
+                Resources associated with the previous cursor are cleaned up.
+    @param aCursor the cursor to use
+*/
+- (nsresult) setCursor: (nsCursor) aCursor;
+
+/*! @method  setCursorWithImage:hotSpotX:hotSpotY:
+ @abstract   Sets the current cursor to a custom image
+ @discussion Sets the current cursor to the cursor given by the aCursorImage argument.
+ Resources associated with the previous cursor are cleaned up.
+ @param aCursorImage the cursor image to use
+ @param aHotSpotX the x coordinate of the cursor's hotspot
+ @param aHotSpotY the y coordinate of the cursor's hotspot
+ @param scaleFactor the scale factor of the target display (2 for a retina display)
+ */
+- (nsresult) setCursorWithImage: (imgIContainer*) aCursorImage hotSpotX: (uint32_t) aHotspotX hotSpotY: (uint32_t) aHotspotY scaleFactor: (CGFloat) scaleFactor;
+
+
+/*! @method     sharedInstance
+    @abstract   Get the Singleton instance of the cursor manager.
+    @discussion Use this method to obtain a reference to the cursor manager.
+    @result a reference to the cursor manager
+*/
++ (nsCursorManager *) sharedInstance;
+
+/*! @method     dispose
+    @abstract   Releases the shared instance of the cursor manager.
+    @discussion Use dispose to clean up the cursor manager and associated cursors.
+*/
++ (void) dispose;
+@end
+
+@interface NSCursor (Undocumented)
+// busyButClickableCursor is an undocumented NSCursor API, but has been in use since
+// at least OS X 10.4 and through 10.9.
++ (NSCursor*)busyButClickableCursor;
+@end
+
+#endif // nsCursorManager_h_
diff --git a/widget/cocoa/nsCursorManager.mm b/widget/cocoa/nsCursorManager.mm
new file mode 100644
index 0000000000..c4281a438a
--- /dev/null
+++ b/widget/cocoa/nsCursorManager.mm
@@ -0,0 +1,308 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "imgIContainer.h"
+#include "nsCocoaUtils.h"
+#include "nsCursorManager.h"
+#include "nsObjCExceptions.h"
+#include <math.h>
+
+static nsCursorManager *gInstance;
+static CGFloat sCursorScaleFactor = 0.0f;
+static imgIContainer *sCursorImgContainer = nullptr;
+static const nsCursor sCustomCursor = eCursorCount;
+
+/*! @category nsCursorManager(PrivateMethods)
+    Private methods for the cursor manager class.
+*/
+@interface nsCursorManager(PrivateMethods)
+/*! @method     getCursor:
+    @abstract   Get a reference to the native Mac representation of a cursor.
+    @discussion Gets a reference to the Mac native implementation of a cursor.
+                If the cursor has been requested before, it is retreived from the cursor cache,
+                otherwise it is created and cached.
+    @param      aCursor the cursor to get
+    @result     the Mac native implementation of the cursor
+*/
+- (nsMacCursor *) getCursor: (nsCursor) aCursor;
+
+/*! @method     setMacCursor:
+ @abstract   Set the current Mac native cursor
+ @discussion Sets the current cursor - this routine is what actually causes the cursor to change.
+ The argument is retained and the old cursor is released.
+ @param      aMacCursor the cursor to set
+ @result     NS_OK
+ */
+- (nsresult) setMacCursor: (nsMacCursor*) aMacCursor;
+
+/*! @method     createCursor:
+    @abstract   Create a Mac native representation of a cursor.
+    @discussion Creates a version of the Mac native representation of this cursor
+    @param      aCursor the cursor to create
+    @result     the Mac native implementation of the cursor
+*/
++ (nsMacCursor *) createCursor: (enum nsCursor) aCursor;
+
+@end
+
+@implementation nsCursorManager
+
++ (nsCursorManager *) sharedInstance
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if (!gInstance) {
+    gInstance = [[nsCursorManager alloc] init];
+  }
+  return gInstance;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
++ (void) dispose
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [gInstance release];
+  gInstance = nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
++ (nsMacCursor *) createCursor: (enum nsCursor) aCursor
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  switch(aCursor)
+  {
+    SEL cursorSelector;
+    case eCursor_standard:
+      return [nsMacCursor cursorWithCursor:[NSCursor arrowCursor] type:aCursor];
+    case eCursor_wait:
+    case eCursor_spinning:
+    {
+      return [nsMacCursor cursorWithCursor:[NSCursor busyButClickableCursor] type:aCursor];
+    }
+    case eCursor_select:
+      return [nsMacCursor cursorWithCursor:[NSCursor IBeamCursor] type:aCursor];
+    case eCursor_hyperlink:
+      return [nsMacCursor cursorWithCursor:[NSCursor pointingHandCursor] type:aCursor];
+    case eCursor_crosshair:
+      return [nsMacCursor cursorWithCursor:[NSCursor crosshairCursor] type:aCursor];
+    case eCursor_move:
+      return [nsMacCursor cursorWithImageNamed:@"move" hotSpot:NSMakePoint(12,12) type:aCursor];
+    case eCursor_help:
+      return [nsMacCursor cursorWithImageNamed:@"help" hotSpot:NSMakePoint(12,12) type:aCursor];
+    case eCursor_copy:
+      cursorSelector = @selector(dragCopyCursor);
+      return [nsMacCursor cursorWithCursor:[NSCursor respondsToSelector:cursorSelector] ?
+              [NSCursor performSelector:cursorSelector] :
+              [NSCursor arrowCursor] type:aCursor];
+    case eCursor_alias:
+      cursorSelector = @selector(dragLinkCursor);
+      return [nsMacCursor cursorWithCursor:[NSCursor respondsToSelector:cursorSelector] ?
+              [NSCursor performSelector:cursorSelector] :
+              [NSCursor arrowCursor] type:aCursor];
+    case eCursor_context_menu:
+      cursorSelector = @selector(contextualMenuCursor);
+      return [nsMacCursor cursorWithCursor:[NSCursor respondsToSelector:cursorSelector] ?
+              [NSCursor performSelector:cursorSelector] :
+              [NSCursor arrowCursor] type:aCursor];
+    case eCursor_cell:
+      return [nsMacCursor cursorWithImageNamed:@"cell" hotSpot:NSMakePoint(12,12) type:aCursor];
+    case eCursor_grab:
+      return [nsMacCursor cursorWithCursor:[NSCursor openHandCursor] type:aCursor];
+    case eCursor_grabbing:
+      return [nsMacCursor cursorWithCursor:[NSCursor closedHandCursor] type:aCursor];
+    case eCursor_zoom_in:
+      return [nsMacCursor cursorWithImageNamed:@"zoomIn" hotSpot:NSMakePoint(10,10) type:aCursor];
+    case eCursor_zoom_out:
+      return [nsMacCursor cursorWithImageNamed:@"zoomOut" hotSpot:NSMakePoint(10,10) type:aCursor];
+    case eCursor_vertical_text:
+      return [nsMacCursor cursorWithImageNamed:@"vtIBeam" hotSpot:NSMakePoint(12,11) type:aCursor];
+    case eCursor_all_scroll:
+      return [nsMacCursor cursorWithCursor:[NSCursor openHandCursor] type:aCursor];
+    case eCursor_not_allowed:
+    case eCursor_no_drop:
+      cursorSelector = @selector(operationNotAllowedCursor);
+      return [nsMacCursor cursorWithCursor:[NSCursor respondsToSelector:cursorSelector] ?
+              [NSCursor performSelector:cursorSelector] :
+              [NSCursor arrowCursor] type:aCursor];
+    // Resize Cursors:
+    // North
+    case eCursor_n_resize:
+        return [nsMacCursor cursorWithCursor:[NSCursor resizeUpCursor] type:aCursor];
+    // North East
+    case eCursor_ne_resize:
+        return [nsMacCursor cursorWithImageNamed:@"sizeNE" hotSpot:NSMakePoint(12,11) type:aCursor];
+    // East
+    case eCursor_e_resize:
+        return [nsMacCursor cursorWithCursor:[NSCursor resizeRightCursor] type:aCursor];
+    // South East
+    case eCursor_se_resize:
+        return [nsMacCursor cursorWithImageNamed:@"sizeSE" hotSpot:NSMakePoint(12,12) type:aCursor];
+    // South
+    case eCursor_s_resize:
+        return [nsMacCursor cursorWithCursor:[NSCursor resizeDownCursor] type:aCursor];
+    // South West
+    case eCursor_sw_resize:
+        return [nsMacCursor cursorWithImageNamed:@"sizeSW" hotSpot:NSMakePoint(10,12) type:aCursor];
+    // West
+    case eCursor_w_resize:
+        return [nsMacCursor cursorWithCursor:[NSCursor resizeLeftCursor] type:aCursor];
+    // North West
+    case eCursor_nw_resize:
+        return [nsMacCursor cursorWithImageNamed:@"sizeNW" hotSpot:NSMakePoint(11,11) type:aCursor];
+    // North & South
+    case eCursor_ns_resize:
+        return [nsMacCursor cursorWithCursor:[NSCursor resizeUpDownCursor] type:aCursor];
+    // East & West
+    case eCursor_ew_resize:
+        return [nsMacCursor cursorWithCursor:[NSCursor resizeLeftRightCursor] type:aCursor];
+    // North East & South West
+    case eCursor_nesw_resize:
+        return [nsMacCursor cursorWithImageNamed:@"sizeNESW" hotSpot:NSMakePoint(12,12) type:aCursor];
+    // North West & South East
+    case eCursor_nwse_resize:
+        return [nsMacCursor cursorWithImageNamed:@"sizeNWSE" hotSpot:NSMakePoint(12,12) type:aCursor];
+    // Column Resize
+    case eCursor_col_resize:
+        return [nsMacCursor cursorWithImageNamed:@"colResize" hotSpot:NSMakePoint(12,12) type:aCursor];
+    // Row Resize
+    case eCursor_row_resize:
+        return [nsMacCursor cursorWithImageNamed:@"rowResize" hotSpot:NSMakePoint(12,12) type:aCursor];
+    default:
+        return [nsMacCursor cursorWithCursor:[NSCursor arrowCursor] type:aCursor];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (id) init
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if ((self = [super init])) {
+    mCursors = [[NSMutableDictionary alloc] initWithCapacity:25];
+  }
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (nsresult) setCursor: (enum nsCursor) aCursor
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // Some plugins mess with our cursors and set a cursor that even
+  // [NSCursor currentCursor] doesn't know about. In case that happens, just
+  // reset the state.
+  [[NSCursor currentCursor] set];
+
+  nsCursor oldType = [mCurrentMacCursor type];
+  if (oldType != aCursor) {
+    if (aCursor == eCursor_none) {
+      [NSCursor hide];
+    } else if (oldType == eCursor_none) {
+      [NSCursor unhide];
+    }
+  }
+  [self setMacCursor:[self getCursor:aCursor]];
+
+  // if a custom cursor was previously set, release sCursorImgContainer
+  if (oldType == sCustomCursor) {
+    NS_IF_RELEASE(sCursorImgContainer);
+  }
+  return NS_OK;
+  
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+- (nsresult) setMacCursor: (nsMacCursor*) aMacCursor
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (mCurrentMacCursor != aMacCursor || ![mCurrentMacCursor isSet]) {
+    [aMacCursor retain];
+    [mCurrentMacCursor unset];
+    [aMacCursor set];
+    [mCurrentMacCursor release];
+    mCurrentMacCursor = aMacCursor;
+  }
+
+  return NS_OK;
+  
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+- (nsresult) setCursorWithImage: (imgIContainer*) aCursorImage hotSpotX: (uint32_t) aHotspotX hotSpotY: (uint32_t) aHotspotY scaleFactor: (CGFloat) scaleFactor
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+  // As the user moves the mouse, this gets called repeatedly with the same aCursorImage
+  if (sCursorImgContainer == aCursorImage && sCursorScaleFactor == scaleFactor && mCurrentMacCursor) {
+    [self setMacCursor:mCurrentMacCursor];
+    return NS_OK;
+  }
+  
+  [[NSCursor currentCursor] set];
+  int32_t width = 0, height = 0;
+  aCursorImage->GetWidth(&width);
+  aCursorImage->GetHeight(&height);
+  // prevent DoS attacks
+  if (width > 128 || height > 128) {
+    return NS_OK;
+  }
+
+  NSImage *cursorImage;
+  nsresult rv = nsCocoaUtils::CreateNSImageFromImageContainer(aCursorImage, imgIContainer::FRAME_FIRST, &cursorImage, scaleFactor);
+  if (NS_FAILED(rv) || !cursorImage) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // if the hotspot is nonsensical, make it 0,0
+  aHotspotX = (aHotspotX > (uint32_t)width - 1) ? 0 : aHotspotX;
+  aHotspotY = (aHotspotY > (uint32_t)height - 1) ? 0 : aHotspotY;
+
+  NSPoint hotSpot = ::NSMakePoint(aHotspotX, aHotspotY);
+  [self setMacCursor:[nsMacCursor cursorWithCursor:[[NSCursor alloc] initWithImage:cursorImage hotSpot:hotSpot] type:sCustomCursor]];
+  [cursorImage release];
+  
+  NS_IF_RELEASE(sCursorImgContainer);
+  sCursorImgContainer = aCursorImage;
+  sCursorScaleFactor = scaleFactor;
+  NS_ADDREF(sCursorImgContainer);
+  
+  return NS_OK;
+  
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+- (nsMacCursor *) getCursor: (enum nsCursor) aCursor
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  nsMacCursor * result = [mCursors objectForKey:[NSNumber numberWithInt:aCursor]];
+  if (!result) {
+    result = [nsCursorManager createCursor:aCursor];
+    [mCursors setObject:result forKey:[NSNumber numberWithInt:aCursor]];
+  }
+  return result;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void) dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mCurrentMacCursor unset];
+  [mCurrentMacCursor release];
+  [mCursors release];
+  NS_IF_RELEASE(sCursorImgContainer);
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@end
diff --git a/widget/cocoa/nsDeviceContextSpecX.h b/widget/cocoa/nsDeviceContextSpecX.h
new file mode 100644
index 0000000000..2df52418a7
--- /dev/null
+++ b/widget/cocoa/nsDeviceContextSpecX.h
@@ -0,0 +1,41 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsDeviceContextSpecX_h_
+#define nsDeviceContextSpecX_h_
+
+#include "nsIDeviceContextSpec.h"
+
+#include <ApplicationServices/ApplicationServices.h>
+
+class nsDeviceContextSpecX : public nsIDeviceContextSpec
+{
+public:
+    NS_DECL_ISUPPORTS
+
+    nsDeviceContextSpecX();
+
+    NS_IMETHOD Init(nsIWidget *aWidget, nsIPrintSettings* aPS, bool aIsPrintPreview) override;
+    virtual already_AddRefed<PrintTarget> MakePrintTarget() final;
+    NS_IMETHOD BeginDocument(const nsAString& aTitle,
+                             const nsAString& aPrintToFileName,
+                             int32_t          aStartPage,
+                             int32_t          aEndPage) override;
+    NS_IMETHOD EndDocument() override;
+    NS_IMETHOD BeginPage() override;
+    NS_IMETHOD EndPage() override;
+
+    void GetPaperRect(double* aTop, double* aLeft, double* aBottom, double* aRight);
+
+protected:
+    virtual ~nsDeviceContextSpecX();
+
+protected:
+    PMPrintSession    mPrintSession;              // printing context.
+    PMPageFormat      mPageFormat;                // page format.
+    PMPrintSettings   mPrintSettings;             // print settings.
+};
+
+#endif //nsDeviceContextSpecX_h_
diff --git a/widget/cocoa/nsDeviceContextSpecX.mm b/widget/cocoa/nsDeviceContextSpecX.mm
new file mode 100644
index 0000000000..d252adef69
--- /dev/null
+++ b/widget/cocoa/nsDeviceContextSpecX.mm
@@ -0,0 +1,165 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsDeviceContextSpecX.h"
+
+#include "mozilla/gfx/PrintTargetCG.h"
+#include "mozilla/RefPtr.h"
+#include "nsCRT.h"
+#include <unistd.h>
+
+#include "nsQueryObject.h"
+#include "nsIServiceManager.h"
+#include "nsPrintSettingsX.h"
+
+// This must be the last include:
+#include "nsObjCExceptions.h"
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+
+nsDeviceContextSpecX::nsDeviceContextSpecX()
+: mPrintSession(NULL)
+, mPageFormat(kPMNoPageFormat)
+, mPrintSettings(kPMNoPrintSettings)
+{
+}
+
+nsDeviceContextSpecX::~nsDeviceContextSpecX()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mPrintSession)
+    ::PMRelease(mPrintSession);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMPL_ISUPPORTS(nsDeviceContextSpecX, nsIDeviceContextSpec)
+
+NS_IMETHODIMP nsDeviceContextSpecX::Init(nsIWidget *aWidget,
+                                         nsIPrintSettings* aPS,
+                                         bool aIsPrintPreview)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  RefPtr<nsPrintSettingsX> settings(do_QueryObject(aPS));
+  if (!settings)
+    return NS_ERROR_NO_INTERFACE;
+
+  mPrintSession = settings->GetPMPrintSession();
+  ::PMRetain(mPrintSession);
+  mPageFormat = settings->GetPMPageFormat();
+  mPrintSettings = settings->GetPMPrintSettings();
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsDeviceContextSpecX::BeginDocument(const nsAString& aTitle, 
+                                                  const nsAString& aPrintToFileName,
+                                                  int32_t          aStartPage, 
+                                                  int32_t          aEndPage)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    if (!aTitle.IsEmpty()) {
+      CFStringRef cfString =
+        ::CFStringCreateWithCharacters(NULL, reinterpret_cast<const UniChar*>(aTitle.BeginReading()),
+                                             aTitle.Length());
+      if (cfString) {
+        ::PMPrintSettingsSetJobName(mPrintSettings, cfString);
+        ::CFRelease(cfString);
+      }
+    }
+
+    OSStatus status;
+    status = ::PMSetFirstPage(mPrintSettings, aStartPage, false);
+    NS_ASSERTION(status == noErr, "PMSetFirstPage failed");
+    status = ::PMSetLastPage(mPrintSettings, aEndPage, false);
+    NS_ASSERTION(status == noErr, "PMSetLastPage failed");
+
+    status = ::PMSessionBeginCGDocumentNoDialog(mPrintSession, mPrintSettings, mPageFormat);
+    if (status != noErr)
+      return NS_ERROR_ABORT;
+
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsDeviceContextSpecX::EndDocument()
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    ::PMSessionEndDocumentNoDialog(mPrintSession);
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsDeviceContextSpecX::BeginPage()
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    PMSessionError(mPrintSession);
+    OSStatus status = ::PMSessionBeginPageNoDialog(mPrintSession, mPageFormat, NULL);
+    if (status != noErr) return NS_ERROR_ABORT;
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsDeviceContextSpecX::EndPage()
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    OSStatus status = ::PMSessionEndPageNoDialog(mPrintSession);
+    if (status != noErr) return NS_ERROR_ABORT;
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void nsDeviceContextSpecX::GetPaperRect(double* aTop, double* aLeft, double* aBottom, double* aRight)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+    PMRect paperRect;
+    ::PMGetAdjustedPaperRect(mPageFormat, &paperRect);
+
+    *aTop = paperRect.top, *aLeft = paperRect.left;
+    *aBottom = paperRect.bottom, *aRight = paperRect.right;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+already_AddRefed<PrintTarget> nsDeviceContextSpecX::MakePrintTarget()
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    double top, left, bottom, right;
+    GetPaperRect(&top, &left, &bottom, &right);
+    const double width = right - left;
+    const double height = bottom - top;
+    IntSize size = IntSize::Floor(width, height);
+
+    CGContextRef context;
+    ::PMSessionGetCGGraphicsContext(mPrintSession, &context);
+
+    if (context) {
+        // Initially, origin is at bottom-left corner of the paper.
+        // Here, we translate it to top-left corner of the paper.
+        CGContextTranslateCTM(context, 0, height);
+        CGContextScaleCTM(context, 1.0, -1.0);
+        return PrintTargetCG::CreateOrNull(context, size);
+    }
+
+    // Apparently we do need this branch - bug 368933.
+    return PrintTargetCG::CreateOrNull(size, SurfaceFormat::A8R8G8B8_UINT32);
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSNULL;
+}
diff --git a/widget/cocoa/nsDragService.h b/widget/cocoa/nsDragService.h
new file mode 100644
index 0000000000..ea6702812a
--- /dev/null
+++ b/widget/cocoa/nsDragService.h
@@ -0,0 +1,55 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsDragService_h_
+#define nsDragService_h_
+
+#include "nsBaseDragService.h"
+
+#include <Cocoa/Cocoa.h>
+
+extern NSString* const kWildcardPboardType;
+extern NSString* const kCorePboardType_url;
+extern NSString* const kCorePboardType_urld;
+extern NSString* const kCorePboardType_urln;
+extern NSString* const kCustomTypesPboardType;
+
+class nsDragService : public nsBaseDragService
+{
+public:
+  nsDragService();
+
+  // nsBaseDragService
+  virtual nsresult InvokeDragSessionImpl(nsIArray* anArrayTransferables,
+                                         nsIScriptableRegion* aRegion,
+                                         uint32_t aActionType);
+  // nsIDragService
+  NS_IMETHOD EndDragSession(bool aDoneDrag);
+
+  // nsIDragSession
+  NS_IMETHOD GetData(nsITransferable * aTransferable, uint32_t aItemIndex);
+  NS_IMETHOD IsDataFlavorSupported(const char *aDataFlavor, bool *_retval);
+  NS_IMETHOD GetNumDropItems(uint32_t * aNumItems);
+
+protected:
+  virtual ~nsDragService();
+
+private:
+
+  NSImage* ConstructDragImage(nsIDOMNode* aDOMNode,
+                              mozilla::LayoutDeviceIntRect* aDragRect,
+                              nsIScriptableRegion* aRegion);
+  bool IsValidType(NSString* availableType, bool allowFileURL);
+  NSString* GetStringForType(NSPasteboardItem* item, const NSString* type,
+                             bool allowFileURL = false);
+  NSString* GetTitleForURL(NSPasteboardItem* item);
+  NSString* GetFilePath(NSPasteboardItem* item);
+
+  nsCOMPtr<nsIArray> mDataItems; // only valid for a drag started within gecko
+  NSView* mNativeDragView;
+  NSEvent* mNativeDragEvent;
+};
+
+#endif // nsDragService_h_
diff --git a/widget/cocoa/nsDragService.mm b/widget/cocoa/nsDragService.mm
new file mode 100644
index 0000000000..c4d8e6ff06
--- /dev/null
+++ b/widget/cocoa/nsDragService.mm
@@ -0,0 +1,669 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Logging.h"
+
+#include "nsArrayUtils.h"
+#include "nsDragService.h"
+#include "nsArrayUtils.h"
+#include "nsObjCExceptions.h"
+#include "nsITransferable.h"
+#include "nsString.h"
+#include "nsClipboard.h"
+#include "nsXPCOM.h"
+#include "nsISupportsPrimitives.h"
+#include "nsCOMPtr.h"
+#include "nsPrimitiveHelpers.h"
+#include "nsLinebreakConverter.h"
+#include "nsIMacUtils.h"
+#include "nsIDOMNode.h"
+#include "nsRect.h"
+#include "nsPoint.h"
+#include "nsIIOService.h"
+#include "nsIDocument.h"
+#include "nsIContent.h"
+#include "nsView.h"
+#include "gfxContext.h"
+#include "nsCocoaUtils.h"
+#include "mozilla/gfx/2D.h"
+#include "gfxPlatform.h"
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+
+extern PRLogModuleInfo* sCocoaLog;
+
+extern void EnsureLogInitialized();
+
+extern NSPasteboard* globalDragPboard;
+extern NSView* gLastDragView;
+extern NSEvent* gLastDragMouseDownEvent;
+extern bool gUserCancelledDrag;
+
+// This global makes the transferable array available to Cocoa's promised
+// file destination callback.
+nsIArray *gDraggedTransferables = nullptr;
+
+NSString* const kWildcardPboardType = @"MozillaWildcard";
+NSString* const kCorePboardType_url  = @"CorePasteboardFlavorType 0x75726C20"; // 'url '  url
+NSString* const kCorePboardType_urld = @"CorePasteboardFlavorType 0x75726C64"; // 'urld'  desc
+NSString* const kCorePboardType_urln = @"CorePasteboardFlavorType 0x75726C6E"; // 'urln'  title
+NSString* const kUTTypeURLName = @"public.url-name";
+NSString* const kCustomTypesPboardType = @"org.mozilla.custom-clipdata";
+
+nsDragService::nsDragService()
+{
+  mNativeDragView = nil;
+  mNativeDragEvent = nil;
+
+  EnsureLogInitialized();
+}
+
+nsDragService::~nsDragService()
+{
+}
+
+static nsresult SetUpDragClipboard(nsIArray* aTransferableArray)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!aTransferableArray)
+    return NS_ERROR_FAILURE;
+
+  uint32_t count = 0;
+  aTransferableArray->GetLength(&count);
+
+  NSPasteboard* dragPBoard = [NSPasteboard pasteboardWithName:NSDragPboard];
+
+  for (uint32_t j = 0; j < count; j++) {
+    nsCOMPtr<nsITransferable> currentTransferable = do_QueryElementAt(aTransferableArray, j);
+    if (!currentTransferable)
+      return NS_ERROR_FAILURE;
+
+    // Transform the transferable to an NSDictionary
+    NSDictionary* pasteboardOutputDict = nsClipboard::PasteboardDictFromTransferable(currentTransferable);
+    if (!pasteboardOutputDict)
+      return NS_ERROR_FAILURE;
+
+    // write everything out to the general pasteboard
+    unsigned int typeCount = [pasteboardOutputDict count];
+    NSMutableArray* types = [NSMutableArray arrayWithCapacity:typeCount + 1];
+    [types addObjectsFromArray:[pasteboardOutputDict allKeys]];
+    // Gecko is initiating this drag so we always want its own views to consider
+    // it. Add our wildcard type to the pasteboard to accomplish this.
+    [types addObject:kWildcardPboardType]; // we don't increase the count for the loop below on purpose
+    [dragPBoard declareTypes:types owner:nil];
+    for (unsigned int k = 0; k < typeCount; k++) {
+      NSString* currentKey = [types objectAtIndex:k];
+      id currentValue = [pasteboardOutputDict valueForKey:currentKey];
+      if (currentKey == NSStringPboardType ||
+          currentKey == kCorePboardType_url ||
+          currentKey == kCorePboardType_urld ||
+          currentKey == kCorePboardType_urln) {
+        [dragPBoard setString:currentValue forType:currentKey];
+      }
+      else if (currentKey == NSHTMLPboardType) {
+        [dragPBoard setString:(nsClipboard::WrapHtmlForSystemPasteboard(currentValue))
+                      forType:currentKey];
+      }
+      else if (currentKey == NSTIFFPboardType ||
+               currentKey == kCustomTypesPboardType) {
+        [dragPBoard setData:currentValue forType:currentKey];
+      }
+      else if (currentKey == NSFilesPromisePboardType ||
+               currentKey == NSFilenamesPboardType) {
+        [dragPBoard setPropertyList:currentValue forType:currentKey];        
+      }
+    }
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NSImage*
+nsDragService::ConstructDragImage(nsIDOMNode* aDOMNode,
+                                  LayoutDeviceIntRect* aDragRect,
+                                  nsIScriptableRegion* aRegion)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  CGFloat scaleFactor = nsCocoaUtils::GetBackingScaleFactor(gLastDragView);
+
+  RefPtr<SourceSurface> surface;
+  nsPresContext* pc;
+  nsresult rv = DrawDrag(aDOMNode, aRegion, mScreenPosition,
+                         aDragRect, &surface, &pc);
+  if (pc && (!aDragRect->width || !aDragRect->height)) {
+    // just use some suitable defaults
+    int32_t size = nsCocoaUtils::CocoaPointsToDevPixels(20, scaleFactor);
+    aDragRect->SetRect(pc->CSSPixelsToDevPixels(mScreenPosition.x),
+                       pc->CSSPixelsToDevPixels(mScreenPosition.y), size, size);
+  }
+
+  if (NS_FAILED(rv) || !surface)
+    return nil;
+
+  uint32_t width = aDragRect->width;
+  uint32_t height = aDragRect->height;
+
+  RefPtr<DataSourceSurface> dataSurface =
+    Factory::CreateDataSourceSurface(IntSize(width, height),
+                                     SurfaceFormat::B8G8R8A8);
+  DataSourceSurface::MappedSurface map;
+  if (!dataSurface->Map(DataSourceSurface::MapType::READ_WRITE, &map)) {
+    return nil;
+  }
+
+  RefPtr<DrawTarget> dt =
+    Factory::CreateDrawTargetForData(BackendType::CAIRO,
+                                     map.mData,
+                                     dataSurface->GetSize(),
+                                     map.mStride,
+                                     dataSurface->GetFormat());
+  if (!dt) {
+    dataSurface->Unmap();
+    return nil;
+  }
+
+  dt->FillRect(gfx::Rect(0, 0, width, height),
+               SurfacePattern(surface, ExtendMode::CLAMP),
+               DrawOptions(1.0f, CompositionOp::OP_SOURCE));
+
+  NSBitmapImageRep* imageRep =
+    [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL
+                                            pixelsWide:width
+                                            pixelsHigh:height
+                                         bitsPerSample:8
+                                       samplesPerPixel:4
+                                              hasAlpha:YES
+                                              isPlanar:NO
+                                        colorSpaceName:NSDeviceRGBColorSpace
+                                           bytesPerRow:width * 4
+                                          bitsPerPixel:32];
+
+  uint8_t* dest = [imageRep bitmapData];
+  for (uint32_t i = 0; i < height; ++i) {
+    uint8_t* src = map.mData + i * map.mStride;
+    for (uint32_t j = 0; j < width; ++j) {
+      // Reduce transparency overall by multipying by a factor. Remember, Alpha
+      // is premultipled here. Also, Quartz likes RGBA, so do that translation as well.
+#ifdef IS_BIG_ENDIAN
+      dest[0] = uint8_t(src[1] * DRAG_TRANSLUCENCY);
+      dest[1] = uint8_t(src[2] * DRAG_TRANSLUCENCY);
+      dest[2] = uint8_t(src[3] * DRAG_TRANSLUCENCY);
+      dest[3] = uint8_t(src[0] * DRAG_TRANSLUCENCY);
+#else
+      dest[0] = uint8_t(src[2] * DRAG_TRANSLUCENCY);
+      dest[1] = uint8_t(src[1] * DRAG_TRANSLUCENCY);
+      dest[2] = uint8_t(src[0] * DRAG_TRANSLUCENCY);
+      dest[3] = uint8_t(src[3] * DRAG_TRANSLUCENCY);
+#endif
+      src += 4;
+      dest += 4;
+    }
+  }
+  dataSurface->Unmap();
+
+  NSImage* image =
+    [[NSImage alloc] initWithSize:NSMakeSize(width / scaleFactor,
+                                             height / scaleFactor)];
+  [image addRepresentation:imageRep];
+  [imageRep release];
+
+  return [image autorelease];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+bool
+nsDragService::IsValidType(NSString* availableType, bool allowFileURL)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  // Prevent exposing fileURL for non-fileURL type.
+  // We need URL provided by dropped webloc file, but don't need file's URL.
+  // kUTTypeFileURL is returned by [NSPasteboard availableTypeFromArray:] for
+  // kUTTypeURL, since it conforms to kUTTypeURL.
+  if (!allowFileURL && [availableType isEqualToString:(id)kUTTypeFileURL]) {
+    return false;
+  }
+
+  return true;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+NSString*
+nsDragService::GetStringForType(NSPasteboardItem* item, const NSString* type,
+                                bool allowFileURL)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSString* availableType = [item availableTypeFromArray:[NSArray arrayWithObjects:(id)type, nil]];
+  if (availableType && IsValidType(availableType, allowFileURL)) {
+    return [item stringForType:(id)availableType];
+  }
+
+  return nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+NSString*
+nsDragService::GetTitleForURL(NSPasteboardItem* item)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSString* name = GetStringForType(item, (const NSString*)kUTTypeURLName);
+  if (name) {
+    return name;
+  }
+
+  NSString* filePath = GetFilePath(item);
+  if (filePath) {
+    return [filePath lastPathComponent];
+  }
+
+  return nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+NSString*
+nsDragService::GetFilePath(NSPasteboardItem* item)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSString* urlString = GetStringForType(item, (const NSString*)kUTTypeFileURL, true);
+  if (urlString) {
+    NSURL* url = [NSURL URLWithString:urlString];
+    if (url) {
+      return [url path];
+    }
+  }
+
+  return nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+// We can only invoke NSView's 'dragImage:at:offset:event:pasteboard:source:slideBack:' from
+// within NSView's 'mouseDown:' or 'mouseDragged:'. Luckily 'mouseDragged' is always on the
+// stack when InvokeDragSession gets called.
+nsresult
+nsDragService::InvokeDragSessionImpl(nsIArray* aTransferableArray,
+                                     nsIScriptableRegion* aDragRgn,
+                                     uint32_t aActionType)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  mDataItems = aTransferableArray;
+
+  // put data on the clipboard
+  if (NS_FAILED(SetUpDragClipboard(aTransferableArray)))
+    return NS_ERROR_FAILURE;
+
+  CGFloat scaleFactor = nsCocoaUtils::GetBackingScaleFactor(gLastDragView);
+
+  LayoutDeviceIntRect dragRect(0, 0, 20, 20);
+  NSImage* image = ConstructDragImage(mSourceNode, &dragRect, aDragRgn);
+  if (!image) {
+    // if no image was returned, just draw a rectangle
+    NSSize size;
+    size.width = nsCocoaUtils::DevPixelsToCocoaPoints(dragRect.width, scaleFactor);
+    size.height = nsCocoaUtils::DevPixelsToCocoaPoints(dragRect.height, scaleFactor);
+    image = [[NSImage alloc] initWithSize:size];
+    [image lockFocus];
+    [[NSColor grayColor] set];
+    NSBezierPath* path = [NSBezierPath bezierPath];
+    [path setLineWidth:2.0];
+    [path moveToPoint:NSMakePoint(0, 0)];
+    [path lineToPoint:NSMakePoint(0, size.height)];
+    [path lineToPoint:NSMakePoint(size.width, size.height)];
+    [path lineToPoint:NSMakePoint(size.width, 0)];
+    [path lineToPoint:NSMakePoint(0, 0)];
+    [path stroke];
+    [image unlockFocus];
+  }
+
+  LayoutDeviceIntPoint pt(dragRect.x, dragRect.YMost());
+  NSPoint point = nsCocoaUtils::DevPixelsToCocoaPoints(pt, scaleFactor);
+  point.y = nsCocoaUtils::FlippedScreenY(point.y);
+
+  point = nsCocoaUtils::ConvertPointFromScreen([gLastDragView window], point);
+  NSPoint localPoint = [gLastDragView convertPoint:point fromView:nil];
+ 
+  // Save the transferables away in case a promised file callback is invoked.
+  gDraggedTransferables = aTransferableArray;
+
+  nsBaseDragService::StartDragSession();
+  nsBaseDragService::OpenDragPopup();
+
+  // We need to retain the view and the event during the drag in case either gets destroyed.
+  mNativeDragView = [gLastDragView retain];
+  mNativeDragEvent = [gLastDragMouseDownEvent retain];
+
+  gUserCancelledDrag = false;
+  [mNativeDragView dragImage:image
+                          at:localPoint
+                      offset:NSZeroSize
+                       event:mNativeDragEvent
+                  pasteboard:[NSPasteboard pasteboardWithName:NSDragPboard]
+                      source:mNativeDragView
+                   slideBack:YES];
+  gUserCancelledDrag = false;
+
+  if (mDoingDrag)
+    nsBaseDragService::EndDragSession(false);
+  
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsDragService::GetData(nsITransferable* aTransferable, uint32_t aItemIndex)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!aTransferable)
+    return NS_ERROR_FAILURE;
+
+  // get flavor list that includes all acceptable flavors (including ones obtained through conversion)
+  nsCOMPtr<nsIArray> flavorList;
+  nsresult rv = aTransferable->FlavorsTransferableCanImport(getter_AddRefs(flavorList));
+  if (NS_FAILED(rv))
+    return NS_ERROR_FAILURE;
+
+  uint32_t acceptableFlavorCount;
+  flavorList->GetLength(&acceptableFlavorCount);
+
+  // if this drag originated within Mozilla we should just use the cached data from
+  // when the drag started if possible
+  if (mDataItems) {
+    nsCOMPtr<nsITransferable> currentTransferable = do_QueryElementAt(mDataItems, aItemIndex);
+    if (currentTransferable) {
+      for (uint32_t i = 0; i < acceptableFlavorCount; i++) {
+        nsCOMPtr<nsISupportsCString> currentFlavor = do_QueryElementAt(flavorList, i);
+        if (!currentFlavor)
+          continue;
+        nsXPIDLCString flavorStr;
+        currentFlavor->ToString(getter_Copies(flavorStr));
+
+        nsCOMPtr<nsISupports> dataSupports;
+        uint32_t dataSize = 0;
+        rv = currentTransferable->GetTransferData(flavorStr, getter_AddRefs(dataSupports), &dataSize);
+        if (NS_SUCCEEDED(rv)) {
+          aTransferable->SetTransferData(flavorStr, dataSupports, dataSize);
+          return NS_OK; // maybe try to fill in more types? Is there a point?
+        }
+      }
+    }
+  }
+
+  // now check the actual clipboard for data
+  for (uint32_t i = 0; i < acceptableFlavorCount; i++) {
+    nsCOMPtr<nsISupportsCString> currentFlavor = do_QueryElementAt(flavorList, i);
+    if (!currentFlavor)
+      continue;
+
+    nsXPIDLCString flavorStr;
+    currentFlavor->ToString(getter_Copies(flavorStr));
+
+    MOZ_LOG(sCocoaLog, LogLevel::Info, ("nsDragService::GetData: looking for clipboard data of type %s\n", flavorStr.get()));
+
+    NSArray* droppedItems = [globalDragPboard pasteboardItems];
+    if (!droppedItems) {
+      continue;
+    }
+
+    uint32_t itemCount = [droppedItems count];
+    if (aItemIndex >= itemCount) {
+      continue;
+    }
+
+    NSPasteboardItem* item = [droppedItems objectAtIndex:aItemIndex];
+    if (!item) {
+      continue;
+    }
+
+    if (flavorStr.EqualsLiteral(kFileMime)) {
+      NSString* filePath = GetFilePath(item);
+      if (!filePath)
+        continue;
+
+      unsigned int stringLength = [filePath length];
+      unsigned int dataLength = (stringLength + 1) * sizeof(char16_t); // in bytes
+      char16_t* clipboardDataPtr = (char16_t*)malloc(dataLength);
+      if (!clipboardDataPtr)
+        return NS_ERROR_OUT_OF_MEMORY;
+      [filePath getCharacters:reinterpret_cast<unichar*>(clipboardDataPtr)];
+      clipboardDataPtr[stringLength] = 0; // null terminate
+
+      nsCOMPtr<nsIFile> file;
+      rv = NS_NewLocalFile(nsDependentString(clipboardDataPtr), true, getter_AddRefs(file));
+      free(clipboardDataPtr);
+      if (NS_FAILED(rv))
+        continue;
+
+      aTransferable->SetTransferData(flavorStr, file, dataLength);
+      
+      break;
+    }
+    else if (flavorStr.EqualsLiteral(kCustomTypesMime)) {
+      NSString* availableType = [item availableTypeFromArray:[NSArray arrayWithObject:kCustomTypesPboardType]];
+      if (!availableType || !IsValidType(availableType, false)) {
+          continue;
+      }
+      NSData *pasteboardData = [item dataForType:availableType];
+      if (!pasteboardData) {
+        continue;
+      }
+
+      unsigned int dataLength = [pasteboardData length];
+      void* clipboardDataPtr = malloc(dataLength);
+      if (!clipboardDataPtr) {
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+      [pasteboardData getBytes:clipboardDataPtr];
+
+      nsCOMPtr<nsISupports> genericDataWrapper;
+      nsPrimitiveHelpers::CreatePrimitiveForData(flavorStr, clipboardDataPtr, dataLength,
+                                                 getter_AddRefs(genericDataWrapper));
+
+      aTransferable->SetTransferData(flavorStr, genericDataWrapper, sizeof(nsIInputStream*));
+      free(clipboardDataPtr);
+      break;
+    }
+
+    NSString* pString = nil;
+    if (flavorStr.EqualsLiteral(kUnicodeMime)) {
+      pString = GetStringForType(item, (const NSString*)kUTTypeUTF8PlainText);
+    } else if (flavorStr.EqualsLiteral(kHTMLMime)) {
+      pString = GetStringForType(item, (const NSString*)kUTTypeHTML);
+    } else if (flavorStr.EqualsLiteral(kURLMime)) {
+      pString = GetStringForType(item, (const NSString*)kUTTypeURL);
+      if (pString) {
+        NSString* title = GetTitleForURL(item);
+        if (!title) {
+          title = pString;
+        }
+        pString = [NSString stringWithFormat:@"%@\n%@", pString, title];
+      }
+    } else if (flavorStr.EqualsLiteral(kURLDataMime)) {
+      pString = GetStringForType(item, (const NSString*)kUTTypeURL);
+    } else if (flavorStr.EqualsLiteral(kURLDescriptionMime)) {
+      pString = GetTitleForURL(item);
+    } else if (flavorStr.EqualsLiteral(kRTFMime)) {
+      pString = GetStringForType(item, (const NSString*)kUTTypeRTF);
+    }
+    if (pString) {
+      NSData* stringData;
+      if (flavorStr.EqualsLiteral(kRTFMime)) {
+        stringData = [pString dataUsingEncoding:NSASCIIStringEncoding];
+      } else {
+        stringData = [pString dataUsingEncoding:NSUnicodeStringEncoding];
+      }
+      unsigned int dataLength = [stringData length];
+      void* clipboardDataPtr = malloc(dataLength);
+      if (!clipboardDataPtr)
+        return NS_ERROR_OUT_OF_MEMORY;
+      [stringData getBytes:clipboardDataPtr];
+
+      // The DOM only wants LF, so convert from MacOS line endings to DOM line endings.
+      int32_t signedDataLength = dataLength;
+      nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(flavorStr, &clipboardDataPtr, &signedDataLength);
+      dataLength = signedDataLength;
+
+      // skip BOM (Byte Order Mark to distinguish little or big endian)      
+      char16_t* clipboardDataPtrNoBOM = (char16_t*)clipboardDataPtr;
+      if ((dataLength > 2) &&
+          ((clipboardDataPtrNoBOM[0] == 0xFEFF) ||
+           (clipboardDataPtrNoBOM[0] == 0xFFFE))) {
+        dataLength -= sizeof(char16_t);
+        clipboardDataPtrNoBOM += 1;
+      }
+
+      nsCOMPtr<nsISupports> genericDataWrapper;
+      nsPrimitiveHelpers::CreatePrimitiveForData(flavorStr, clipboardDataPtrNoBOM, dataLength,
+                                                 getter_AddRefs(genericDataWrapper));
+      aTransferable->SetTransferData(flavorStr, genericDataWrapper, dataLength);
+      free(clipboardDataPtr);
+      break;
+    }
+
+    // We have never supported this on Mac OS X, we should someday. Normally dragging images
+    // in is accomplished with a file path drag instead of the image data itself.
+    /*
+    if (flavorStr.EqualsLiteral(kPNGImageMime) || flavorStr.EqualsLiteral(kJPEGImageMime) ||
+        flavorStr.EqualsLiteral(kJPGImageMime) || flavorStr.EqualsLiteral(kGIFImageMime)) {
+
+    }
+    */
+  }
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsDragService::IsDataFlavorSupported(const char *aDataFlavor, bool *_retval)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  *_retval = false;
+
+  if (!globalDragPboard)
+    return NS_ERROR_FAILURE;
+
+  nsDependentCString dataFlavor(aDataFlavor);
+
+  // first see if we have data for this in our cached transferable
+  if (mDataItems) {
+    uint32_t dataItemsCount;
+    mDataItems->GetLength(&dataItemsCount);
+    for (unsigned int i = 0; i < dataItemsCount; i++) {
+      nsCOMPtr<nsITransferable> currentTransferable = do_QueryElementAt(mDataItems, i);
+      if (!currentTransferable)
+        continue;
+
+      nsCOMPtr<nsIArray> flavorList;
+      nsresult rv = currentTransferable->FlavorsTransferableCanImport(getter_AddRefs(flavorList));
+      if (NS_FAILED(rv))
+        continue;
+
+      uint32_t flavorCount;
+      flavorList->GetLength(&flavorCount);
+      for (uint32_t j = 0; j < flavorCount; j++) {
+        nsCOMPtr<nsISupportsCString> currentFlavor = do_QueryElementAt(flavorList, j);
+        if (!currentFlavor)
+          continue;
+        nsXPIDLCString flavorStr;
+        currentFlavor->ToString(getter_Copies(flavorStr));
+        if (dataFlavor.Equals(flavorStr)) {
+          *_retval = true;
+          return NS_OK;
+        }
+      }
+    }
+  }
+
+  const NSString* type = nil;
+  bool allowFileURL = false;
+  if (dataFlavor.EqualsLiteral(kFileMime)) {
+    type = (const NSString*)kUTTypeFileURL;
+    allowFileURL = true;
+  } else if (dataFlavor.EqualsLiteral(kUnicodeMime)) {
+    type = (const NSString*)kUTTypeUTF8PlainText;
+  } else if (dataFlavor.EqualsLiteral(kHTMLMime)) {
+    type = (const NSString*)kUTTypeHTML;
+  } else if (dataFlavor.EqualsLiteral(kURLMime) ||
+             dataFlavor.EqualsLiteral(kURLDataMime)) {
+    type = (const NSString*)kUTTypeURL;
+  } else if (dataFlavor.EqualsLiteral(kURLDescriptionMime)) {
+    type = (const NSString*)kUTTypeURLName;
+  } else if (dataFlavor.EqualsLiteral(kRTFMime)) {
+    type = (const NSString*)kUTTypeRTF;
+  } else if (dataFlavor.EqualsLiteral(kCustomTypesMime)) {
+    type = (const NSString*)kCustomTypesPboardType;
+  }
+
+  NSString* availableType = [globalDragPboard availableTypeFromArray:[NSArray arrayWithObjects:(id)type, nil]];
+  if (availableType && IsValidType(availableType, allowFileURL)) {
+    *_retval = true;
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsDragService::GetNumDropItems(uint32_t* aNumItems)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  *aNumItems = 0;
+
+  // first check to see if we have a number of items cached
+  if (mDataItems) {
+    mDataItems->GetLength(aNumItems);
+    return NS_OK;
+  }
+
+  NSArray* droppedItems = [globalDragPboard pasteboardItems];
+  if (droppedItems) {
+    *aNumItems = [droppedItems count];
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsDragService::EndDragSession(bool aDoneDrag)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (mNativeDragView) {
+    [mNativeDragView release];
+    mNativeDragView = nil;
+  }
+  if (mNativeDragEvent) {
+    [mNativeDragEvent release];
+    mNativeDragEvent = nil;
+  }
+
+  mUserCancelled = gUserCancelledDrag;
+
+  nsresult rv = nsBaseDragService::EndDragSession(aDoneDrag);
+  mDataItems = nullptr;
+  return rv;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
diff --git a/widget/cocoa/nsFilePicker.h b/widget/cocoa/nsFilePicker.h
new file mode 100644
index 0000000000..1aeb22cc18
--- /dev/null
+++ b/widget/cocoa/nsFilePicker.h
@@ -0,0 +1,74 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsFilePicker_h_
+#define nsFilePicker_h_
+
+#include "nsBaseFilePicker.h"
+#include "nsString.h"
+#include "nsIFileChannel.h"
+#include "nsIFile.h"
+#include "nsCOMArray.h"
+#include "nsTArray.h"
+
+class nsILocalFileMac;
+@class NSArray;
+
+class nsFilePicker : public nsBaseFilePicker
+{
+public:
+  nsFilePicker(); 
+
+  NS_DECL_ISUPPORTS
+
+  // nsIFilePicker (less what's in nsBaseFilePicker)
+  NS_IMETHOD GetDefaultString(nsAString& aDefaultString) override;
+  NS_IMETHOD SetDefaultString(const nsAString& aDefaultString) override;
+  NS_IMETHOD GetDefaultExtension(nsAString& aDefaultExtension) override;
+  NS_IMETHOD GetFilterIndex(int32_t *aFilterIndex) override;
+  NS_IMETHOD SetFilterIndex(int32_t aFilterIndex) override;
+  NS_IMETHOD SetDefaultExtension(const nsAString& aDefaultExtension) override;
+  NS_IMETHOD GetFile(nsIFile * *aFile) override;
+  NS_IMETHOD GetFileURL(nsIURI * *aFileURL) override;
+  NS_IMETHOD GetFiles(nsISimpleEnumerator **aFiles) override;
+  NS_IMETHOD Show(int16_t *_retval) override; 
+  NS_IMETHOD AppendFilter(const nsAString& aTitle, const nsAString& aFilter) override;
+
+  /**
+   * Returns the current filter list in the format used by Cocoa's NSSavePanel
+   * and NSOpenPanel.
+   * Returns nil if no filter currently apply.
+   */
+  NSArray* GetFilterList();
+
+protected:
+  virtual ~nsFilePicker();
+
+  virtual void InitNative(nsIWidget *aParent, const nsAString& aTitle) override;
+
+  // actual implementations of get/put dialogs using NSOpenPanel & NSSavePanel
+  // aFile is an existing but unspecified file. These functions must specify it.
+  //
+  // will return |returnCancel| or |returnOK| as result.
+  int16_t GetLocalFiles(const nsString& inTitle, bool inAllowMultiple, nsCOMArray<nsIFile>& outFiles);
+  int16_t GetLocalFolder(const nsString& inTitle, nsIFile** outFile);
+  int16_t PutLocalFile(const nsString& inTitle, const nsString& inDefaultName, nsIFile** outFile);
+
+  void     SetDialogTitle(const nsString& inTitle, id aDialog);
+  NSString *PanelDefaultDirectory();
+  NSView* GetAccessoryView();
+                                                
+  nsString               mTitle;
+  nsCOMArray<nsIFile>    mFiles;
+  nsString               mDefault;
+
+  nsTArray<nsString>     mFilters; 
+  nsTArray<nsString>     mTitles;
+
+  int32_t                mSelectedTypeIndex;
+};
+
+#endif // nsFilePicker_h_
diff --git a/widget/cocoa/nsFilePicker.mm b/widget/cocoa/nsFilePicker.mm
new file mode 100644
index 0000000000..5213dee241
--- /dev/null
+++ b/widget/cocoa/nsFilePicker.mm
@@ -0,0 +1,676 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsFilePicker.h"
+#include "nsCOMPtr.h"
+#include "nsReadableUtils.h"
+#include "nsNetUtil.h"
+#include "nsIComponentManager.h"
+#include "nsIFile.h"
+#include "nsILocalFileMac.h"
+#include "nsIURL.h"
+#include "nsArrayEnumerator.h"
+#include "nsIStringBundle.h"
+#include "nsCocoaUtils.h"
+#include "mozilla/Preferences.h"
+
+// This must be included last:
+#include "nsObjCExceptions.h"
+
+using namespace mozilla;
+
+const float kAccessoryViewPadding = 5;
+const int   kSaveTypeControlTag = 1;
+
+static bool gCallSecretHiddenFileAPI = false;
+const char kShowHiddenFilesPref[] = "filepicker.showHiddenFiles";
+
+/**
+ * This class is an observer of NSPopUpButton selection change.
+ */
+@interface NSPopUpButtonObserver : NSObject
+{
+  NSPopUpButton* mPopUpButton;
+  NSOpenPanel*   mOpenPanel;
+  nsFilePicker*  mFilePicker;
+}
+- (void) setPopUpButton:(NSPopUpButton*)aPopUpButton;
+- (void) setOpenPanel:(NSOpenPanel*)aOpenPanel;
+- (void) setFilePicker:(nsFilePicker*)aFilePicker;
+- (void) menuChangedItem:(NSNotification*)aSender;
+@end
+
+NS_IMPL_ISUPPORTS(nsFilePicker, nsIFilePicker)
+
+// We never want to call the secret show hidden files API unless the pref
+// has been set. Once the pref has been set we always need to call it even
+// if it disappears so that we stop showing hidden files if a user deletes
+// the pref. If the secret API was used once and things worked out it should
+// continue working for subsequent calls so the user is at no more risk.
+static void SetShowHiddenFileState(NSSavePanel* panel)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  bool show = false;
+  if (NS_SUCCEEDED(Preferences::GetBool(kShowHiddenFilesPref, &show))) {
+    gCallSecretHiddenFileAPI = true;
+  }
+
+  if (gCallSecretHiddenFileAPI) {
+    // invoke a method to get a Cocoa-internal nav view
+    SEL navViewSelector = @selector(_navView);
+    NSMethodSignature* navViewSignature = [panel methodSignatureForSelector:navViewSelector];
+    if (!navViewSignature)
+      return;
+    NSInvocation* navViewInvocation = [NSInvocation invocationWithMethodSignature:navViewSignature];
+    [navViewInvocation setSelector:navViewSelector];
+    [navViewInvocation setTarget:panel];
+    [navViewInvocation invoke];
+
+    // get the returned nav view
+    id navView = nil;
+    [navViewInvocation getReturnValue:&navView];
+
+    // invoke the secret show hidden file state method on the nav view
+    SEL showHiddenFilesSelector = @selector(setShowsHiddenFiles:);
+    NSMethodSignature* showHiddenFilesSignature = [navView methodSignatureForSelector:showHiddenFilesSelector];
+    if (!showHiddenFilesSignature)
+      return;
+    NSInvocation* showHiddenFilesInvocation = [NSInvocation invocationWithMethodSignature:showHiddenFilesSignature];
+    [showHiddenFilesInvocation setSelector:showHiddenFilesSelector];
+    [showHiddenFilesInvocation setTarget:navView];
+    [showHiddenFilesInvocation setArgument:&show atIndex:2];
+    [showHiddenFilesInvocation invoke];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsFilePicker::nsFilePicker()
+: mSelectedTypeIndex(0)
+{
+}
+
+nsFilePicker::~nsFilePicker()
+{
+}
+
+void
+nsFilePicker::InitNative(nsIWidget *aParent, const nsAString& aTitle)
+{
+  mTitle = aTitle;
+}
+
+NSView* nsFilePicker::GetAccessoryView()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSView* accessoryView = [[[NSView alloc] initWithFrame:NSMakeRect(0, 0, 0, 0)] autorelease];
+
+  // Set a label's default value.
+  NSString* label = @"Format:";
+
+  // Try to get the localized string.
+  nsCOMPtr<nsIStringBundleService> sbs = do_GetService(NS_STRINGBUNDLE_CONTRACTID);
+  nsCOMPtr<nsIStringBundle> bundle;
+  nsresult rv = sbs->CreateBundle("chrome://global/locale/filepicker.properties", getter_AddRefs(bundle));
+  if (NS_SUCCEEDED(rv)) {
+    nsXPIDLString locaLabel;
+    bundle->GetStringFromName(u"formatLabel", getter_Copies(locaLabel));
+    if (locaLabel) {
+      label = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(locaLabel.get())
+                                      length:locaLabel.Length()];
+    }
+  }
+
+  // set up label text field
+  NSTextField* textField = [[[NSTextField alloc] init] autorelease];
+  [textField setEditable:NO];
+  [textField setSelectable:NO];
+  [textField setDrawsBackground:NO];
+  [textField setBezeled:NO];
+  [textField setBordered:NO];
+  [textField setFont:[NSFont labelFontOfSize:13.0]];
+  [textField setStringValue:label];
+  [textField setTag:0];
+  [textField sizeToFit];
+
+  // set up popup button
+  NSPopUpButton* popupButton = [[[NSPopUpButton alloc] initWithFrame:NSMakeRect(0, 0, 0, 0) pullsDown:NO] autorelease];
+  uint32_t numMenuItems = mTitles.Length();
+  for (uint32_t i = 0; i < numMenuItems; i++) {
+    const nsString& currentTitle = mTitles[i];
+    NSString *titleString;
+    if (currentTitle.IsEmpty()) {
+      const nsString& currentFilter = mFilters[i];
+      titleString = [[NSString alloc] initWithCharacters:reinterpret_cast<const unichar*>(currentFilter.get())
+                                                  length:currentFilter.Length()];
+    }
+    else {
+      titleString = [[NSString alloc] initWithCharacters:reinterpret_cast<const unichar*>(currentTitle.get())
+                                                  length:currentTitle.Length()];
+    }
+    [popupButton addItemWithTitle:titleString];
+    [titleString release];
+  }
+  if (mSelectedTypeIndex >= 0 && (uint32_t)mSelectedTypeIndex < numMenuItems)
+    [popupButton selectItemAtIndex:mSelectedTypeIndex];
+  [popupButton setTag:kSaveTypeControlTag];
+  [popupButton sizeToFit]; // we have to do sizeToFit to get the height calculated for us
+  // This is just a default width that works well, doesn't truncate the vast majority of
+  // things that might end up in the menu.
+  [popupButton setFrameSize:NSMakeSize(180, [popupButton frame].size.height)];
+
+  // position everything based on control sizes with kAccessoryViewPadding pix padding
+  // on each side kAccessoryViewPadding pix horizontal padding between controls
+  float greatestHeight = [textField frame].size.height;
+  if ([popupButton frame].size.height > greatestHeight)
+    greatestHeight = [popupButton frame].size.height;
+  float totalViewHeight = greatestHeight + kAccessoryViewPadding * 2;
+  float totalViewWidth  = [textField frame].size.width + [popupButton frame].size.width + kAccessoryViewPadding * 3;
+  [accessoryView setFrameSize:NSMakeSize(totalViewWidth, totalViewHeight)];
+
+  float textFieldOriginY = ((greatestHeight - [textField frame].size.height) / 2 + 1) + kAccessoryViewPadding;
+  [textField setFrameOrigin:NSMakePoint(kAccessoryViewPadding, textFieldOriginY)];
+  
+  float popupOriginX = [textField frame].size.width + kAccessoryViewPadding * 2;
+  float popupOriginY = ((greatestHeight - [popupButton frame].size.height) / 2) + kAccessoryViewPadding;
+  [popupButton setFrameOrigin:NSMakePoint(popupOriginX, popupOriginY)];
+
+  [accessoryView addSubview:textField];
+  [accessoryView addSubview:popupButton];
+  return accessoryView;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+// Display the file dialog
+NS_IMETHODIMP nsFilePicker::Show(int16_t *retval)
+{
+  NS_ENSURE_ARG_POINTER(retval);
+
+  *retval = returnCancel;
+
+  int16_t userClicksOK = returnCancel;
+
+// Random questions from DHH:
+//
+// Why do we pass mTitle, mDefault to the functions?  Can GetLocalFile. PutLocalFile,
+// and GetLocalFolder get called someplace else?  It generates a bunch of warnings
+// as it is right now.
+//
+// I think we could easily combine GetLocalFile and GetLocalFolder together, just
+// setting panel pick options based on mMode.  I didn't do it here b/c I wanted to 
+// make this look as much like Carbon nsFilePicker as possible.  
+
+  mFiles.Clear();
+  nsCOMPtr<nsIFile> theFile;
+
+  switch (mMode)
+  {
+    case modeOpen:
+      userClicksOK = GetLocalFiles(mTitle, false, mFiles);
+      break;
+    
+    case modeOpenMultiple:
+      userClicksOK = GetLocalFiles(mTitle, true, mFiles);
+      break;
+      
+    case modeSave:
+      userClicksOK = PutLocalFile(mTitle, mDefault, getter_AddRefs(theFile));
+      break;
+      
+    case modeGetFolder:
+      userClicksOK = GetLocalFolder(mTitle, getter_AddRefs(theFile));
+      break;
+    
+    default:
+      NS_ERROR("Unknown file picker mode");
+      break;
+  }
+
+  if (theFile)
+    mFiles.AppendObject(theFile);
+  
+  *retval = userClicksOK;
+  return NS_OK;
+}
+
+static
+void UpdatePanelFileTypes(NSOpenPanel* aPanel, NSArray* aFilters)
+{
+  // If we show all file types, also "expose" bundles' contents.
+  [aPanel setTreatsFilePackagesAsDirectories:!aFilters];
+
+  [aPanel setAllowedFileTypes:aFilters];
+}
+
+@implementation NSPopUpButtonObserver
+- (void) setPopUpButton:(NSPopUpButton*)aPopUpButton
+{
+  mPopUpButton = aPopUpButton;
+}
+
+- (void) setOpenPanel:(NSOpenPanel*)aOpenPanel
+{
+  mOpenPanel = aOpenPanel;
+}
+
+- (void) setFilePicker:(nsFilePicker*)aFilePicker
+{
+  mFilePicker = aFilePicker;
+}
+
+- (void) menuChangedItem:(NSNotification *)aSender
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+  int32_t selectedItem = [mPopUpButton indexOfSelectedItem];
+  if (selectedItem < 0) {
+    return;
+  }
+
+  mFilePicker->SetFilterIndex(selectedItem);
+  UpdatePanelFileTypes(mOpenPanel, mFilePicker->GetFilterList());
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN();
+}
+@end
+
+// Use OpenPanel to do a GetFile. Returns |returnOK| if the user presses OK in the dialog. 
+int16_t
+nsFilePicker::GetLocalFiles(const nsString& inTitle, bool inAllowMultiple, nsCOMArray<nsIFile>& outFiles)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  int16_t retVal = (int16_t)returnCancel;
+  NSOpenPanel *thePanel = [NSOpenPanel openPanel];
+
+  SetShowHiddenFileState(thePanel);
+
+  // Set the options for how the get file dialog will appear
+  SetDialogTitle(inTitle, thePanel);
+  [thePanel setAllowsMultipleSelection:inAllowMultiple];
+  [thePanel setCanSelectHiddenExtension:YES];
+  [thePanel setCanChooseDirectories:NO];
+  [thePanel setCanChooseFiles:YES];
+  [thePanel setResolvesAliases:YES]; //this is default - probably doesn't need to be set
+  
+  // Get filters
+  // filters may be null, if we should allow all file types.
+  NSArray *filters = GetFilterList();
+
+  // set up default directory
+  NSString *theDir = PanelDefaultDirectory();
+  
+  // if this is the "Choose application..." dialog, and no other start
+  // dir has been set, then use the Applications folder.
+  if (!theDir) {
+    if (filters && [filters count] == 1 &&
+        [(NSString *)[filters objectAtIndex:0] isEqualToString:@"app"])
+      theDir = @"/Applications/";
+    else
+      theDir = @"";
+  }
+
+  if (theDir) {
+    [thePanel setDirectoryURL:[NSURL fileURLWithPath:theDir isDirectory:YES]];
+  }
+
+  int result;
+  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  if (mFilters.Length() > 1) {
+    // [NSURL initWithString:] (below) throws an exception if URLString is nil.
+
+    NSPopUpButtonObserver* observer = [[NSPopUpButtonObserver alloc] init];
+
+    NSView* accessoryView = GetAccessoryView();
+    [thePanel setAccessoryView:accessoryView];
+
+    [observer setPopUpButton:[accessoryView viewWithTag:kSaveTypeControlTag]];
+    [observer setOpenPanel:thePanel];
+    [observer setFilePicker:this];
+
+    [[NSNotificationCenter defaultCenter]
+      addObserver:observer
+      selector:@selector(menuChangedItem:)
+      name:NSMenuWillSendActionNotification object:nil];
+
+    UpdatePanelFileTypes(thePanel, filters);
+    result = [thePanel runModal];
+
+    [[NSNotificationCenter defaultCenter] removeObserver:observer];
+    [observer release];
+  } else {
+    // If we show all file types, also "expose" bundles' contents.
+    if (!filters) {
+      [thePanel setTreatsFilePackagesAsDirectories:YES];
+    }
+    [thePanel setAllowedFileTypes:filters];
+    result = [thePanel runModal];
+  }
+  nsCocoaUtils::CleanUpAfterNativeAppModalDialog();
+  
+  if (result == NSFileHandlingPanelCancelButton)
+    return retVal;
+
+  // Converts data from a NSArray of NSURL to the returned format.
+  // We should be careful to not call [thePanel URLs] more than once given that
+  // it creates a new array each time.
+  // We are using Fast Enumeration, thus the NSURL array is created once then
+  // iterated.
+  for (NSURL* url in [thePanel URLs]) {
+    if (!url) {
+      continue;
+    }
+
+    nsCOMPtr<nsIFile> localFile;
+    NS_NewLocalFile(EmptyString(), true, getter_AddRefs(localFile));
+    nsCOMPtr<nsILocalFileMac> macLocalFile = do_QueryInterface(localFile);
+    if (macLocalFile && NS_SUCCEEDED(macLocalFile->InitWithCFURL((CFURLRef)url))) {
+      outFiles.AppendObject(localFile);
+    }
+  }
+
+  if (outFiles.Count() > 0)
+    retVal = returnOK;
+
+  return retVal;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0);
+}
+
+// Use OpenPanel to do a GetFolder. Returns |returnOK| if the user presses OK in the dialog.
+int16_t
+nsFilePicker::GetLocalFolder(const nsString& inTitle, nsIFile** outFile)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+  NS_ASSERTION(outFile, "this protected member function expects a null initialized out pointer");
+  
+  int16_t retVal = (int16_t)returnCancel;
+  NSOpenPanel *thePanel = [NSOpenPanel openPanel];
+
+  SetShowHiddenFileState(thePanel);
+
+  // Set the options for how the get file dialog will appear
+  SetDialogTitle(inTitle, thePanel);
+  [thePanel setAllowsMultipleSelection:NO];   //this is default -probably doesn't need to be set
+  [thePanel setCanSelectHiddenExtension:YES];
+  [thePanel setCanChooseDirectories:YES];
+  [thePanel setCanChooseFiles:NO];
+  [thePanel setResolvesAliases:YES];          //this is default - probably doesn't need to be set
+  [thePanel setCanCreateDirectories:YES];
+  
+  // packages != folders
+  [thePanel setTreatsFilePackagesAsDirectories:NO];
+
+  // set up default directory
+  NSString *theDir = PanelDefaultDirectory();
+  if (theDir) {
+    [thePanel setDirectoryURL:[NSURL fileURLWithPath:theDir isDirectory:YES]];
+  }
+  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  int result = [thePanel runModal];
+  nsCocoaUtils::CleanUpAfterNativeAppModalDialog();
+
+  if (result == NSFileHandlingPanelCancelButton)
+    return retVal;
+
+  // get the path for the folder (we allow just 1, so that's all we get)
+  NSURL *theURL = [[thePanel URLs] objectAtIndex:0];
+  if (theURL) {
+    nsCOMPtr<nsIFile> localFile;
+    NS_NewLocalFile(EmptyString(), true, getter_AddRefs(localFile));
+    nsCOMPtr<nsILocalFileMac> macLocalFile = do_QueryInterface(localFile);
+    if (macLocalFile && NS_SUCCEEDED(macLocalFile->InitWithCFURL((CFURLRef)theURL))) {
+      *outFile = localFile;
+      NS_ADDREF(*outFile);
+      retVal = returnOK;
+    }
+  }
+
+  return retVal;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0);
+}
+
+// Returns |returnOK| if the user presses OK in the dialog.
+int16_t
+nsFilePicker::PutLocalFile(const nsString& inTitle, const nsString& inDefaultName, nsIFile** outFile)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+  NS_ASSERTION(outFile, "this protected member function expects a null initialized out pointer");
+
+  int16_t retVal = returnCancel;
+  NSSavePanel *thePanel = [NSSavePanel savePanel];
+
+  SetShowHiddenFileState(thePanel);
+
+  SetDialogTitle(inTitle, thePanel);
+
+  // set up accessory view for file format options
+  NSView* accessoryView = GetAccessoryView();
+  [thePanel setAccessoryView:accessoryView];
+
+  // set up default file name
+  NSString* defaultFilename = [NSString stringWithCharacters:(const unichar*)inDefaultName.get() length:inDefaultName.Length()];
+
+  // set up allowed types; this prevents the extension from being selected
+  // use the UTI for the file type to allow alternate extensions (e.g., jpg vs. jpeg)
+  NSString* extension = defaultFilename.pathExtension;
+  if (extension.length != 0) {
+    CFStringRef type = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (CFStringRef)extension, NULL);
+
+    if (type) {
+      thePanel.allowedFileTypes = @[(NSString*)type];
+      CFRelease(type);
+    } else {
+      // if there's no UTI for the file extension, use the extension itself.
+      thePanel.allowedFileTypes = @[extension];
+    }
+  }
+  // Allow users to change the extension.
+  thePanel.allowsOtherFileTypes = YES;
+
+  // set up default directory
+  NSString *theDir = PanelDefaultDirectory();
+  if (theDir) {
+    [thePanel setDirectoryURL:[NSURL fileURLWithPath:theDir isDirectory:YES]];
+  }
+
+  // load the panel
+  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  [thePanel setNameFieldStringValue:defaultFilename];
+  int result = [thePanel runModal];
+  nsCocoaUtils::CleanUpAfterNativeAppModalDialog();
+  if (result == NSFileHandlingPanelCancelButton)
+    return retVal;
+
+  // get the save type
+  NSPopUpButton* popupButton = [accessoryView viewWithTag:kSaveTypeControlTag];
+  if (popupButton) {
+    mSelectedTypeIndex = [popupButton indexOfSelectedItem];
+  }
+
+  NSURL* fileURL = [thePanel URL];
+  if (fileURL) { 
+    nsCOMPtr<nsIFile> localFile;
+    NS_NewLocalFile(EmptyString(), true, getter_AddRefs(localFile));
+    nsCOMPtr<nsILocalFileMac> macLocalFile = do_QueryInterface(localFile);
+    if (macLocalFile && NS_SUCCEEDED(macLocalFile->InitWithCFURL((CFURLRef)fileURL))) {
+      *outFile = localFile;
+      NS_ADDREF(*outFile);
+      // We tell if we are replacing or not by just looking to see if the file exists.
+      // The user could not have hit OK and not meant to replace the file.
+      if ([[NSFileManager defaultManager] fileExistsAtPath:[fileURL path]])
+        retVal = returnReplace;
+      else
+        retVal = returnOK;
+    }
+  }
+
+  return retVal;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0);
+}
+
+NSArray *
+nsFilePicker::GetFilterList()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if (!mFilters.Length()) {
+    return nil;
+  }
+
+  if (mFilters.Length() <= (uint32_t)mSelectedTypeIndex) {
+    NS_WARNING("An out of range index has been selected. Using the first index instead.");
+    mSelectedTypeIndex = 0;
+  }
+
+  const nsString& filterWide = mFilters[mSelectedTypeIndex];
+  if (!filterWide.Length()) {
+    return nil;
+  }
+
+  if (filterWide.Equals(NS_LITERAL_STRING("*"))) {
+    return nil;
+  }
+
+  // The extensions in filterWide are in the format "*.ext" but are expected
+  // in the format "ext" by NSOpenPanel. So we need to filter some characters.
+  NSMutableString* filterString = [[[NSMutableString alloc] initWithString:
+                                    [NSString stringWithCharacters:reinterpret_cast<const unichar*>(filterWide.get())
+                                                            length:filterWide.Length()]] autorelease];
+  NSCharacterSet *set = [NSCharacterSet characterSetWithCharactersInString:@". *"];
+  NSRange range = [filterString rangeOfCharacterFromSet:set];
+  while (range.length) {
+    [filterString replaceCharactersInRange:range withString:@""];
+    range = [filterString rangeOfCharacterFromSet:set];
+  }
+
+  return [[[NSArray alloc] initWithArray:
+           [filterString componentsSeparatedByString:@";"]] autorelease];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+// Sets the dialog title to whatever it should be.  If it fails, eh,
+// the OS will provide a sensible default.
+void
+nsFilePicker::SetDialogTitle(const nsString& inTitle, id aPanel)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [aPanel setTitle:[NSString stringWithCharacters:(const unichar*)inTitle.get() length:inTitle.Length()]];
+
+  if (!mOkButtonLabel.IsEmpty()) {
+    [aPanel setPrompt:[NSString stringWithCharacters:(const unichar*)mOkButtonLabel.get() length:mOkButtonLabel.Length()]];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+} 
+
+// Converts path from an nsIFile into a NSString path
+// If it fails, returns an empty string.
+NSString *
+nsFilePicker::PanelDefaultDirectory()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSString *directory = nil;
+  if (mDisplayDirectory) {
+    nsAutoString pathStr;
+    mDisplayDirectory->GetPath(pathStr);
+    directory = [[[NSString alloc] initWithCharacters:reinterpret_cast<const unichar*>(pathStr.get())
+                                               length:pathStr.Length()] autorelease];
+  }
+  return directory;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+NS_IMETHODIMP nsFilePicker::GetFile(nsIFile **aFile)
+{
+  NS_ENSURE_ARG_POINTER(aFile);
+  *aFile = nullptr;
+  
+  // just return the first file
+  if (mFiles.Count() > 0) {
+    *aFile = mFiles.ObjectAt(0);
+    NS_IF_ADDREF(*aFile);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsFilePicker::GetFileURL(nsIURI **aFileURL)
+{
+  NS_ENSURE_ARG_POINTER(aFileURL);
+  *aFileURL = nullptr;
+
+  if (mFiles.Count() == 0)
+    return NS_OK;
+
+  return NS_NewFileURI(aFileURL, mFiles.ObjectAt(0));
+}
+
+NS_IMETHODIMP nsFilePicker::GetFiles(nsISimpleEnumerator **aFiles)
+{
+  return NS_NewArrayEnumerator(aFiles, mFiles);
+}
+
+NS_IMETHODIMP nsFilePicker::SetDefaultString(const nsAString& aString)
+{
+  mDefault = aString;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsFilePicker::GetDefaultString(nsAString& aString)
+{
+  return NS_ERROR_FAILURE;
+}
+
+// The default extension to use for files
+NS_IMETHODIMP nsFilePicker::GetDefaultExtension(nsAString& aExtension)
+{
+  aExtension.Truncate();
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsFilePicker::SetDefaultExtension(const nsAString& aExtension)
+{
+  return NS_OK;
+}
+
+// Append an entry to the filters array
+NS_IMETHODIMP
+nsFilePicker::AppendFilter(const nsAString& aTitle, const nsAString& aFilter)
+{
+  // "..apps" has to be translated with native executable extensions.
+  if (aFilter.EqualsLiteral("..apps")) {
+    mFilters.AppendElement(NS_LITERAL_STRING("*.app"));
+  } else {
+    mFilters.AppendElement(aFilter);
+  }
+  mTitles.AppendElement(aTitle);
+  
+  return NS_OK;
+}
+
+// Get the filter index - do we still need this?
+NS_IMETHODIMP nsFilePicker::GetFilterIndex(int32_t *aFilterIndex)
+{
+  *aFilterIndex = mSelectedTypeIndex;
+  return NS_OK;
+}
+
+// Set the filter index - do we still need this?
+NS_IMETHODIMP nsFilePicker::SetFilterIndex(int32_t aFilterIndex)
+{
+  mSelectedTypeIndex = aFilterIndex;
+  return NS_OK;
+}
diff --git a/widget/cocoa/nsIdleServiceX.h b/widget/cocoa/nsIdleServiceX.h
new file mode 100644
index 0000000000..f0b3d92ed5
--- /dev/null
+++ b/widget/cocoa/nsIdleServiceX.h
@@ -0,0 +1,33 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsIdleServiceX_h_
+#define nsIdleServiceX_h_
+
+#include "nsIdleService.h"
+
+class nsIdleServiceX : public nsIdleService
+{
+public:
+  NS_DECL_ISUPPORTS_INHERITED
+
+  bool PollIdleTime(uint32_t* aIdleTime) override;
+
+  static already_AddRefed<nsIdleServiceX> GetInstance() 
+  {
+    RefPtr<nsIdleService> idleService = nsIdleService::GetInstance();
+    if (!idleService) {
+      idleService = new nsIdleServiceX();
+    }
+    
+    return idleService.forget().downcast<nsIdleServiceX>();
+  }
+  
+protected:
+    nsIdleServiceX() { }
+    virtual ~nsIdleServiceX() { }
+    bool UsePollMode() override;
+};
+
+#endif // nsIdleServiceX_h_
diff --git a/widget/cocoa/nsIdleServiceX.mm b/widget/cocoa/nsIdleServiceX.mm
new file mode 100644
index 0000000000..234a154146
--- /dev/null
+++ b/widget/cocoa/nsIdleServiceX.mm
@@ -0,0 +1,77 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIdleServiceX.h"
+#include "nsObjCExceptions.h"
+#include "nsIServiceManager.h"
+#import <Foundation/Foundation.h>
+
+NS_IMPL_ISUPPORTS_INHERITED0(nsIdleServiceX, nsIdleService)
+
+bool
+nsIdleServiceX::PollIdleTime(uint32_t *aIdleTime)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  kern_return_t rval;
+  mach_port_t masterPort;
+
+  rval = IOMasterPort(kIOMasterPortDefault, &masterPort);
+  if (rval != KERN_SUCCESS)
+    return false;
+
+  io_iterator_t hidItr;
+  rval = IOServiceGetMatchingServices(masterPort,
+                                      IOServiceMatching("IOHIDSystem"),
+                                      &hidItr);
+
+  if (rval != KERN_SUCCESS)
+    return false;
+  NS_ASSERTION(hidItr, "Our iterator is null, but it ought not to be!");
+
+  io_registry_entry_t entry = IOIteratorNext(hidItr);
+  NS_ASSERTION(entry, "Our IO Registry Entry is null, but it shouldn't be!");
+
+  IOObjectRelease(hidItr);
+
+  NSMutableDictionary *hidProps;
+  rval = IORegistryEntryCreateCFProperties(entry,
+                                           (CFMutableDictionaryRef*)&hidProps,
+                                           kCFAllocatorDefault, 0);
+  if (rval != KERN_SUCCESS)
+    return false;
+  NS_ASSERTION(hidProps, "HIDProperties is null, but no error was returned.");
+  [hidProps autorelease];
+
+  id idleObj = [hidProps objectForKey:@"HIDIdleTime"];
+  NS_ASSERTION([idleObj isKindOfClass: [NSData class]] ||
+               [idleObj isKindOfClass: [NSNumber class]],
+               "What we got for the idle object is not what we expect!");
+
+  uint64_t time;
+  if ([idleObj isKindOfClass: [NSData class]])
+    [idleObj getBytes: &time];
+  else
+    time = [idleObj unsignedLongLongValue];
+
+  IOObjectRelease(entry);
+
+  // convert to ms from ns
+  time /= 1000000;
+  if (time > UINT32_MAX) // Overflow will occur
+    return false;
+
+  *aIdleTime = static_cast<uint32_t>(time);
+
+  return true;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+bool
+nsIdleServiceX::UsePollMode()
+{
+  return true;
+}
+
diff --git a/widget/cocoa/nsLookAndFeel.h b/widget/cocoa/nsLookAndFeel.h
new file mode 100644
index 0000000000..2ad31a2aa1
--- /dev/null
+++ b/widget/cocoa/nsLookAndFeel.h
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsLookAndFeel_h_
+#define nsLookAndFeel_h_
+#include "nsXPLookAndFeel.h"
+
+class nsLookAndFeel: public nsXPLookAndFeel {
+public:
+  nsLookAndFeel();
+  virtual ~nsLookAndFeel();
+
+  virtual nsresult NativeGetColor(ColorID aID, nscolor &aResult);
+  virtual nsresult GetIntImpl(IntID aID, int32_t &aResult);
+  virtual nsresult GetFloatImpl(FloatID aID, float &aResult);
+  virtual bool GetFontImpl(FontID aID, nsString& aFontName,
+                           gfxFontStyle& aFontStyle,
+                           float aDevPixPerCSSPixel);
+  virtual char16_t GetPasswordCharacterImpl()
+  {
+    // unicode value for the bullet character, used for password textfields.
+    return 0x2022;
+  }
+
+  static bool UseOverlayScrollbars();
+
+  virtual nsTArray<LookAndFeelInt> GetIntCacheImpl();
+  virtual void SetIntCacheImpl(const nsTArray<LookAndFeelInt>& aLookAndFeelIntCache);
+
+  virtual void RefreshImpl();
+
+protected:
+  static bool SystemWantsOverlayScrollbars();
+  static bool AllowOverlayScrollbarsOverlap();
+
+private:
+  int32_t mUseOverlayScrollbars;
+  bool mUseOverlayScrollbarsCached;
+
+  int32_t mAllowOverlayScrollbarsOverlap;
+  bool mAllowOverlayScrollbarsOverlapCached;
+};
+
+#endif // nsLookAndFeel_h_
diff --git a/widget/cocoa/nsLookAndFeel.mm b/widget/cocoa/nsLookAndFeel.mm
new file mode 100644
index 0000000000..0b68cd0e4f
--- /dev/null
+++ b/widget/cocoa/nsLookAndFeel.mm
@@ -0,0 +1,584 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsLookAndFeel.h"
+#include "nsCocoaFeatures.h"
+#include "nsIServiceManager.h"
+#include "nsNativeThemeColors.h"
+#include "nsStyleConsts.h"
+#include "nsCocoaFeatures.h"
+#include "nsIContent.h"
+#include "gfxFont.h"
+#include "gfxFontConstants.h"
+#include "gfxPlatformMac.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/widget/WidgetMessageUtils.h"
+
+#import <Cocoa/Cocoa.h>
+
+// This must be included last:
+#include "nsObjCExceptions.h"
+
+enum {
+  mozNSScrollerStyleLegacy       = 0,
+  mozNSScrollerStyleOverlay      = 1
+};
+typedef NSInteger mozNSScrollerStyle;
+
+@interface NSScroller(AvailableSinceLion)
++ (mozNSScrollerStyle)preferredScrollerStyle;
+@end
+
+nsLookAndFeel::nsLookAndFeel()
+ : nsXPLookAndFeel()
+ , mUseOverlayScrollbars(-1)
+ , mUseOverlayScrollbarsCached(false)
+ , mAllowOverlayScrollbarsOverlap(-1)
+ , mAllowOverlayScrollbarsOverlapCached(false)
+{
+}
+
+nsLookAndFeel::~nsLookAndFeel()
+{
+}
+
+static nscolor GetColorFromNSColor(NSColor* aColor)
+{
+  NSColor* deviceColor = [aColor colorUsingColorSpaceName:NSDeviceRGBColorSpace];
+  return NS_RGB((unsigned int)([deviceColor redComponent] * 255.0),
+                (unsigned int)([deviceColor greenComponent] * 255.0),
+                (unsigned int)([deviceColor blueComponent] * 255.0));
+}
+
+static nscolor GetColorFromNSColorWithAlpha(NSColor* aColor, float alpha)
+{
+  NSColor* deviceColor = [aColor colorUsingColorSpaceName:NSDeviceRGBColorSpace];
+  return NS_RGBA((unsigned int)([deviceColor redComponent] * 255.0),
+                 (unsigned int)([deviceColor greenComponent] * 255.0),
+                 (unsigned int)([deviceColor blueComponent] * 255.0),
+                 (unsigned int)(alpha * 255.0));
+}
+
+nsresult
+nsLookAndFeel::NativeGetColor(ColorID aID, nscolor &aColor)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  nsresult res = NS_OK;
+
+  switch (aID) {
+    case eColorID_WindowBackground:
+      aColor = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_WindowForeground:
+      aColor = NS_RGB(0x00,0x00,0x00);
+      break;
+    case eColorID_WidgetBackground:
+      aColor = NS_RGB(0xdd,0xdd,0xdd);
+      break;
+    case eColorID_WidgetForeground:
+      aColor = NS_RGB(0x00,0x00,0x00);
+      break;
+    case eColorID_WidgetSelectBackground:
+      aColor = NS_RGB(0x80,0x80,0x80);
+      break;
+    case eColorID_WidgetSelectForeground:
+      aColor = NS_RGB(0x00,0x00,0x80);
+      break;
+    case eColorID_Widget3DHighlight:
+      aColor = NS_RGB(0xa0,0xa0,0xa0);
+      break;
+    case eColorID_Widget3DShadow:
+      aColor = NS_RGB(0x40,0x40,0x40);
+      break;
+    case eColorID_TextBackground:
+      aColor = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_TextForeground:
+      aColor = NS_RGB(0x00,0x00,0x00);
+      break;
+    case eColorID_TextSelectBackground:
+      aColor = GetColorFromNSColor([NSColor selectedTextBackgroundColor]);
+      break;
+    case eColorID_highlight: // CSS2 color
+      aColor = GetColorFromNSColor([NSColor alternateSelectedControlColor]);
+      break;
+    case eColorID__moz_menuhover:
+      aColor = GetColorFromNSColor([NSColor alternateSelectedControlColor]);
+      break;
+    case eColorID_TextSelectForeground:
+      GetColor(eColorID_TextSelectBackground, aColor);
+      if (aColor == 0x000000)
+        aColor = NS_RGB(0xff,0xff,0xff);
+      else
+        aColor = NS_DONT_CHANGE_COLOR;
+      break;
+    case eColorID_highlighttext:  // CSS2 color
+    case eColorID__moz_menuhovertext:
+      aColor = GetColorFromNSColor([NSColor alternateSelectedControlTextColor]);
+      break;
+    case eColorID_IMESelectedRawTextBackground:
+    case eColorID_IMESelectedConvertedTextBackground:
+    case eColorID_IMERawInputBackground:
+    case eColorID_IMEConvertedTextBackground:
+      aColor = NS_TRANSPARENT;
+      break;
+    case eColorID_IMESelectedRawTextForeground:
+    case eColorID_IMESelectedConvertedTextForeground:
+    case eColorID_IMERawInputForeground:
+    case eColorID_IMEConvertedTextForeground:
+      aColor = NS_SAME_AS_FOREGROUND_COLOR;
+      break;
+    case eColorID_IMERawInputUnderline:
+    case eColorID_IMEConvertedTextUnderline:
+      aColor = NS_40PERCENT_FOREGROUND_COLOR;
+      break;
+    case eColorID_IMESelectedRawTextUnderline:
+    case eColorID_IMESelectedConvertedTextUnderline:
+      aColor = NS_SAME_AS_FOREGROUND_COLOR;
+      break;
+    case eColorID_SpellCheckerUnderline:
+      aColor = NS_RGB(0xff, 0, 0);
+      break;
+
+      //
+      // css2 system colors http://www.w3.org/TR/REC-CSS2/ui.html#system-colors
+      //
+      // It's really hard to effectively map these to the Appearance Manager properly,
+      // since they are modeled word for word after the win32 system colors and don't have any
+      // real counterparts in the Mac world. I'm sure we'll be tweaking these for
+      // years to come.
+      //
+      // Thanks to mpt26@student.canterbury.ac.nz for the hardcoded values that form the defaults
+      //  if querying the Appearance Manager fails ;)
+      //
+    case eColorID__moz_mac_buttonactivetext:
+    case eColorID__moz_mac_defaultbuttontext:
+      if (nsCocoaFeatures::OnYosemiteOrLater()) {
+        aColor = NS_RGB(0xFF,0xFF,0xFF);
+        break;
+      }
+      // Otherwise fall through and return the regular button text:
+
+    case eColorID_buttontext:
+    case eColorID__moz_buttonhovertext:
+      aColor = GetColorFromNSColor([NSColor controlTextColor]);
+      break;
+    case eColorID_captiontext:
+    case eColorID_menutext:
+    case eColorID_infotext:
+    case eColorID__moz_menubartext:
+      aColor = GetColorFromNSColor([NSColor textColor]);
+      break;
+    case eColorID_windowtext:
+      aColor = GetColorFromNSColor([NSColor windowFrameTextColor]);
+      break;
+    case eColorID_activecaption:
+      aColor = GetColorFromNSColor([NSColor gridColor]);
+      break;
+    case eColorID_activeborder:
+      aColor = GetColorFromNSColor([NSColor keyboardFocusIndicatorColor]);
+      break;
+     case eColorID_appworkspace:
+      aColor = NS_RGB(0xFF,0xFF,0xFF);
+      break;
+    case eColorID_background:
+      aColor = NS_RGB(0x63,0x63,0xCE);
+      break;
+    case eColorID_buttonface:
+    case eColorID__moz_buttonhoverface:
+      aColor = NS_RGB(0xF0,0xF0,0xF0);
+      break;
+    case eColorID_buttonhighlight:
+      aColor = NS_RGB(0xFF,0xFF,0xFF);
+      break;
+    case eColorID_buttonshadow:
+      aColor = NS_RGB(0xDC,0xDC,0xDC);
+      break;
+    case eColorID_graytext:
+      aColor = GetColorFromNSColor([NSColor disabledControlTextColor]);
+      break;
+    case eColorID_inactiveborder:
+      aColor = GetColorFromNSColor([NSColor controlBackgroundColor]);
+      break;
+    case eColorID_inactivecaption:
+      aColor = GetColorFromNSColor([NSColor controlBackgroundColor]);
+      break;
+    case eColorID_inactivecaptiontext:
+      aColor = NS_RGB(0x45,0x45,0x45);
+      break;
+    case eColorID_scrollbar:
+      aColor = GetColorFromNSColor([NSColor scrollBarColor]);
+      break;
+    case eColorID_threeddarkshadow:
+      aColor = NS_RGB(0xDC,0xDC,0xDC);
+      break;
+    case eColorID_threedshadow:
+      aColor = NS_RGB(0xE0,0xE0,0xE0);
+      break;
+    case eColorID_threedface:
+      aColor = NS_RGB(0xF0,0xF0,0xF0);
+      break;
+    case eColorID_threedhighlight:
+      aColor = GetColorFromNSColor([NSColor highlightColor]);
+      break;
+    case eColorID_threedlightshadow:
+      aColor = NS_RGB(0xDA,0xDA,0xDA);
+      break;
+    case eColorID_menu:
+      aColor = GetColorFromNSColor([NSColor alternateSelectedControlTextColor]);
+      break;
+    case eColorID_infobackground:
+      aColor = NS_RGB(0xFF,0xFF,0xC7);
+      break;
+    case eColorID_windowframe:
+      aColor = GetColorFromNSColor([NSColor gridColor]);
+      break;
+    case eColorID_window:
+    case eColorID__moz_field:
+    case eColorID__moz_combobox:
+      aColor = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID__moz_fieldtext:
+    case eColorID__moz_comboboxtext:
+      aColor = GetColorFromNSColor([NSColor controlTextColor]);
+      break;
+    case eColorID__moz_dialog:
+      aColor = GetColorFromNSColor([NSColor controlHighlightColor]);
+      break;
+    case eColorID__moz_dialogtext:
+    case eColorID__moz_cellhighlighttext:
+    case eColorID__moz_html_cellhighlighttext:
+      aColor = GetColorFromNSColor([NSColor controlTextColor]);
+      break;
+    case eColorID__moz_dragtargetzone:
+      aColor = GetColorFromNSColor([NSColor selectedControlColor]);
+      break;
+    case eColorID__moz_mac_chrome_active:
+    case eColorID__moz_mac_chrome_inactive: {
+      int grey = NativeGreyColorAsInt(toolbarFillGrey, (aID == eColorID__moz_mac_chrome_active));
+      aColor = NS_RGB(grey, grey, grey);
+    }
+      break;
+    case eColorID__moz_mac_focusring:
+      aColor = GetColorFromNSColorWithAlpha([NSColor keyboardFocusIndicatorColor], 0.48);
+      break;
+    case eColorID__moz_mac_menushadow:
+      aColor = NS_RGB(0xA3,0xA3,0xA3);
+      break;
+    case eColorID__moz_mac_menutextdisable:
+      aColor = NS_RGB(0x98,0x98,0x98);
+      break;
+    case eColorID__moz_mac_menutextselect:
+      aColor = GetColorFromNSColor([NSColor selectedMenuItemTextColor]);
+      break;
+    case eColorID__moz_mac_disabledtoolbartext:
+      aColor = GetColorFromNSColor([NSColor disabledControlTextColor]);
+      break;
+    case eColorID__moz_mac_menuselect:
+      aColor = GetColorFromNSColor([NSColor alternateSelectedControlColor]);
+      break;
+    case eColorID__moz_buttondefault:
+      aColor = NS_RGB(0xDC,0xDC,0xDC);
+      break;
+    case eColorID__moz_cellhighlight:
+    case eColorID__moz_html_cellhighlight:
+    case eColorID__moz_mac_secondaryhighlight:
+      // For inactive list selection
+      aColor = GetColorFromNSColor([NSColor secondarySelectedControlColor]);
+      break;
+    case eColorID__moz_eventreerow:
+      // Background color of even list rows.
+      aColor = GetColorFromNSColor([[NSColor controlAlternatingRowBackgroundColors] objectAtIndex:0]);
+      break;
+    case eColorID__moz_oddtreerow:
+      // Background color of odd list rows.
+      aColor = GetColorFromNSColor([[NSColor controlAlternatingRowBackgroundColors] objectAtIndex:1]);
+      break;
+    case eColorID__moz_nativehyperlinktext:
+      // There appears to be no available system defined color. HARDCODING to the appropriate color.
+      aColor = NS_RGB(0x14,0x4F,0xAE);
+      break;
+    default:
+      NS_WARNING("Someone asked nsILookAndFeel for a color I don't know about");
+      aColor = NS_RGB(0xff,0xff,0xff);
+      res = NS_ERROR_FAILURE;
+      break;
+    }
+
+  return res;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult
+nsLookAndFeel::GetIntImpl(IntID aID, int32_t &aResult)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  nsresult res = nsXPLookAndFeel::GetIntImpl(aID, aResult);
+  if (NS_SUCCEEDED(res))
+    return res;
+  res = NS_OK;
+
+  switch (aID) {
+    case eIntID_CaretBlinkTime:
+      aResult = 567;
+      break;
+    case eIntID_CaretWidth:
+      aResult = 1;
+      break;
+    case eIntID_ShowCaretDuringSelection:
+      aResult = 0;
+      break;
+    case eIntID_SelectTextfieldsOnKeyFocus:
+      // Select textfield content when focused by kbd
+      // used by EventStateManager::sTextfieldSelectModel
+      aResult = 1;
+      break;
+    case eIntID_SubmenuDelay:
+      aResult = 200;
+      break;
+    case eIntID_TooltipDelay:
+      aResult = 500;
+      break;
+    case eIntID_MenusCanOverlapOSBar:
+      // xul popups are not allowed to overlap the menubar.
+      aResult = 0;
+      break;
+    case eIntID_SkipNavigatingDisabledMenuItem:
+      aResult = 1;
+      break;
+    case eIntID_DragThresholdX:
+    case eIntID_DragThresholdY:
+      aResult = 4;
+      break;
+    case eIntID_ScrollArrowStyle:
+      aResult = eScrollArrow_None;
+      break;
+    case eIntID_ScrollSliderStyle:
+      aResult = eScrollThumbStyle_Proportional;
+      break;
+    case eIntID_UseOverlayScrollbars:
+      if (!mUseOverlayScrollbarsCached) {
+        mUseOverlayScrollbars = SystemWantsOverlayScrollbars() ? 1 : 0;
+        mUseOverlayScrollbarsCached = true;
+      }
+      aResult = mUseOverlayScrollbars;
+      break;
+    case eIntID_AllowOverlayScrollbarsOverlap:
+      if (!mAllowOverlayScrollbarsOverlapCached) {
+        mAllowOverlayScrollbarsOverlap = AllowOverlayScrollbarsOverlap() ? 1 : 0;
+        mAllowOverlayScrollbarsOverlapCached = true;
+      }
+      aResult = mAllowOverlayScrollbarsOverlap;
+      break;
+    case eIntID_ScrollbarDisplayOnMouseMove:
+      aResult = 0;
+      break;
+    case eIntID_ScrollbarFadeBeginDelay:
+      aResult = 450;
+      break;
+    case eIntID_ScrollbarFadeDuration:
+      aResult = 200;
+      break;
+    case eIntID_TreeOpenDelay:
+      aResult = 1000;
+      break;
+    case eIntID_TreeCloseDelay:
+      aResult = 1000;
+      break;
+    case eIntID_TreeLazyScrollDelay:
+      aResult = 150;
+      break;
+    case eIntID_TreeScrollDelay:
+      aResult = 100;
+      break;
+    case eIntID_TreeScrollLinesMax:
+      aResult = 3;
+      break;
+    case eIntID_DWMCompositor:
+    case eIntID_WindowsClassic:
+    case eIntID_WindowsDefaultTheme:
+    case eIntID_TouchEnabled:
+    case eIntID_WindowsThemeIdentifier:
+    case eIntID_OperatingSystemVersionIdentifier:
+      aResult = 0;
+      res = NS_ERROR_NOT_IMPLEMENTED;
+      break;
+    case eIntID_MacGraphiteTheme:
+      aResult = [NSColor currentControlTint] == NSGraphiteControlTint;
+      break;
+    case eIntID_MacLionTheme:
+      aResult = 1;
+      break;
+    case eIntID_MacYosemiteTheme:
+      aResult = nsCocoaFeatures::OnYosemiteOrLater();
+      break;
+    case eIntID_AlertNotificationOrigin:
+      aResult = NS_ALERT_TOP;
+      break;
+    case eIntID_TabFocusModel:
+      aResult = [NSApp isFullKeyboardAccessEnabled] ?
+                  nsIContent::eTabFocus_any : nsIContent::eTabFocus_textControlsMask;
+      break;
+    case eIntID_ScrollToClick:
+    {
+      aResult = [[NSUserDefaults standardUserDefaults] boolForKey:@"AppleScrollerPagingBehavior"];
+    }
+      break;
+    case eIntID_ChosenMenuItemsShouldBlink:
+      aResult = 1;
+      break;
+    case eIntID_IMERawInputUnderlineStyle:
+    case eIntID_IMEConvertedTextUnderlineStyle:
+    case eIntID_IMESelectedRawTextUnderlineStyle:
+    case eIntID_IMESelectedConvertedTextUnderline:
+      aResult = NS_STYLE_TEXT_DECORATION_STYLE_SOLID;
+      break;
+    case eIntID_SpellCheckerUnderlineStyle:
+      aResult = NS_STYLE_TEXT_DECORATION_STYLE_DOTTED;
+      break;
+    case eIntID_ScrollbarButtonAutoRepeatBehavior:
+      aResult = 0;
+      break;
+    case eIntID_SwipeAnimationEnabled:
+      aResult = 0;
+      if ([NSEvent respondsToSelector:@selector(
+            isSwipeTrackingFromScrollEventsEnabled)]) {
+        aResult = [NSEvent isSwipeTrackingFromScrollEventsEnabled] ? 1 : 0;
+      }
+      break;
+    case eIntID_ColorPickerAvailable:
+      aResult = 1;
+      break;
+    case eIntID_ContextMenuOffsetVertical:
+      aResult = -6;
+      break;
+    case eIntID_ContextMenuOffsetHorizontal:
+      aResult = 1;
+      break;
+    default:
+      aResult = 0;
+      res = NS_ERROR_FAILURE;
+  }
+  return res;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult
+nsLookAndFeel::GetFloatImpl(FloatID aID, float &aResult)
+{
+  nsresult res = nsXPLookAndFeel::GetFloatImpl(aID, aResult);
+  if (NS_SUCCEEDED(res))
+    return res;
+  res = NS_OK;
+
+  switch (aID) {
+    case eFloatID_IMEUnderlineRelativeSize:
+      aResult = 2.0f;
+      break;
+    case eFloatID_SpellCheckerUnderlineRelativeSize:
+      aResult = 2.0f;
+      break;
+    default:
+      aResult = -1.0;
+      res = NS_ERROR_FAILURE;
+  }
+
+  return res;
+}
+
+bool nsLookAndFeel::UseOverlayScrollbars()
+{
+  return GetInt(eIntID_UseOverlayScrollbars) != 0;
+}
+
+bool nsLookAndFeel::SystemWantsOverlayScrollbars()
+{
+  return ([NSScroller respondsToSelector:@selector(preferredScrollerStyle)] &&
+          [NSScroller preferredScrollerStyle] == mozNSScrollerStyleOverlay);
+}
+
+bool nsLookAndFeel::AllowOverlayScrollbarsOverlap()
+{
+  return (UseOverlayScrollbars());
+}
+
+bool
+nsLookAndFeel::GetFontImpl(FontID aID, nsString &aFontName,
+                           gfxFontStyle &aFontStyle,
+                           float aDevPixPerCSSPixel)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+    // hack for now
+    if (aID == eFont_Window || aID == eFont_Document) {
+        aFontStyle.style      = NS_FONT_STYLE_NORMAL;
+        aFontStyle.weight     = NS_FONT_WEIGHT_NORMAL;
+        aFontStyle.stretch    = NS_FONT_STRETCH_NORMAL;
+        aFontStyle.size       = 14 * aDevPixPerCSSPixel;
+        aFontStyle.systemFont = true;
+
+        aFontName.AssignLiteral("sans-serif");
+        return true;
+    }
+
+    gfxPlatformMac::LookupSystemFont(aID, aFontName, aFontStyle,
+                                     aDevPixPerCSSPixel);
+
+    return true;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+nsTArray<LookAndFeelInt>
+nsLookAndFeel::GetIntCacheImpl()
+{
+  nsTArray<LookAndFeelInt> lookAndFeelIntCache =
+    nsXPLookAndFeel::GetIntCacheImpl();
+
+  LookAndFeelInt useOverlayScrollbars;
+  useOverlayScrollbars.id = eIntID_UseOverlayScrollbars;
+  useOverlayScrollbars.value = GetInt(eIntID_UseOverlayScrollbars);
+  lookAndFeelIntCache.AppendElement(useOverlayScrollbars);
+
+  LookAndFeelInt allowOverlayScrollbarsOverlap;
+  allowOverlayScrollbarsOverlap.id = eIntID_AllowOverlayScrollbarsOverlap;
+  allowOverlayScrollbarsOverlap.value = GetInt(eIntID_AllowOverlayScrollbarsOverlap);
+  lookAndFeelIntCache.AppendElement(allowOverlayScrollbarsOverlap);
+
+  return lookAndFeelIntCache;
+}
+
+void
+nsLookAndFeel::SetIntCacheImpl(const nsTArray<LookAndFeelInt>& aLookAndFeelIntCache)
+{
+  for (auto entry : aLookAndFeelIntCache) {
+    switch(entry.id) {
+      case eIntID_UseOverlayScrollbars:
+        mUseOverlayScrollbars = entry.value;
+        mUseOverlayScrollbarsCached = true;
+        break;
+      case eIntID_AllowOverlayScrollbarsOverlap:
+        mAllowOverlayScrollbarsOverlap = entry.value;
+        mAllowOverlayScrollbarsOverlapCached = true;
+        break;
+    }
+  }
+}
+
+void
+nsLookAndFeel::RefreshImpl()
+{
+  // We should only clear the cache if we're in the main browser process.
+  // Otherwise, we should wait for the parent to inform us of new values
+  // to cache via LookAndFeel::SetIntCache.
+  if (XRE_IsParentProcess()) {
+    mUseOverlayScrollbarsCached = false;
+    mAllowOverlayScrollbarsOverlapCached = false;
+  }
+}
diff --git a/widget/cocoa/nsMacCursor.h b/widget/cocoa/nsMacCursor.h
new file mode 100644
index 0000000000..cf9c84c7ea
--- /dev/null
+++ b/widget/cocoa/nsMacCursor.h
@@ -0,0 +1,105 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsMacCursor_h_
+#define nsMacCursor_h_
+
+#import <Cocoa/Cocoa.h>
+#import "nsIWidget.h"
+
+/*! @class      nsMacCursor
+    @abstract   Represents a native Mac cursor.
+    @discussion <code>nsMacCursor</code> provides a simple API for creating and working with native Macintosh cursors.
+                Cursors can be created used without needing to be aware of the way different cursors are implemented,
+                in particular the details of managing an animated cursor are hidden.
+*/
+@interface nsMacCursor : NSObject
+{
+  @private
+  NSTimer *mTimer;
+  @protected
+  nsCursor mType;
+  int mFrameCounter;    
+}
+
+/*! @method     cursorWithCursor:
+    @abstract   Create a cursor by specifying a Cocoa <code>NSCursor</code>.
+    @discussion Creates a cursor representing the given Cocoa built-in cursor.
+    @param      aCursor the <code>NSCursor</code> to use
+    @param      aType the corresponding <code>nsCursor</code> constant
+    @result     an autoreleased instance of <code>nsMacCursor</code> representing the given <code>NSCursor</code>
+ */
++ (nsMacCursor *) cursorWithCursor: (NSCursor *) aCursor type: (nsCursor) aType;
+
+/*! @method     cursorWithImageNamed:hotSpot:type:
+    @abstract   Create a cursor by specifying the name of an image resource to use for the cursor and a hotspot.
+    @discussion Creates a cursor by loading the named image using the <code>+[NSImage imageNamed:]</code> method.
+                <p>The image must be compatible with any restrictions laid down by <code>NSCursor</code>. These vary
+                by operating system version.</p>
+                <p>The hotspot precisely determines the point where the user clicks when using the cursor.</p>
+    @param      aCursor the name of the image to use for the cursor
+    @param      aPoint the point within the cursor to use as the hotspot
+    @param      aType the corresponding <code>nsCursor</code> constant
+    @result     an autoreleased instance of <code>nsMacCursor</code> that uses the given image and hotspot
+ */
++ (nsMacCursor *) cursorWithImageNamed: (NSString *) aCursorImage hotSpot: (NSPoint) aPoint type: (nsCursor) aType;
+
+/*! @method     cursorWithFrames:type:
+    @abstract   Create an animated cursor by specifying the frames to use for the animation.
+    @discussion Creates a cursor that will animate by cycling through the given frames. Each element of the array
+                must be an instance of <code>NSCursor</code>
+    @param      aCursorFrames an array of <code>NSCursor</code>, representing the frames of an animated cursor, in the
+                order they should be played.
+    @param      aType the corresponding <code>nsCursor</code> constant
+    @result     an autoreleased instance of <code>nsMacCursor</code> that will animate the given cursor frames
+ */
++ (nsMacCursor *) cursorWithFrames: (NSArray *) aCursorFrames type: (nsCursor) aType;
+
+/*! @method     cocoaCursorWithImageNamed:hotSpot:
+    @abstract   Create a Cocoa NSCursor object with a Gecko image resource name and a hotspot point.
+    @discussion Create a Cocoa NSCursor object with a Gecko image resource name and a hotspot point.
+    @param      imageName the name of the gecko image resource, "tiff" extension is assumed, do not append.
+    @param      aPoint the point within the cursor to use as the hotspot
+    @result     an autoreleased instance of <code>nsMacCursor</code> that will animate the given cursor frames
+ */
++ (NSCursor *) cocoaCursorWithImageNamed: (NSString *) imageName hotSpot: (NSPoint) aPoint;
+
+/*! @method     isSet
+    @abstract   Determines whether this cursor is currently active.
+    @discussion This can be helpful when the Cocoa NSCursor state can be influenced without going
+                through nsCursorManager.
+    @result     whether the cursor is currently set
+ */
+- (BOOL) isSet;
+
+/*! @method     set
+    @abstract   Set the cursor.
+    @discussion Makes this cursor the current cursor. If the cursor is animated, the animation is started.
+ */
+- (void) set;
+
+/*! @method     unset
+    @abstract   Unset the cursor. The cursor will return to the default (usually the arrow cursor).
+    @discussion Unsets the cursor. If the cursor is animated, the animation is stopped.
+ */
+- (void) unset;
+
+/*! @method     isAnimated
+    @abstract   Tests whether this cursor is animated.
+    @discussion Use this method to determine whether a cursor is animated
+    @result     YES if the cursor is animated (has more than one frame), NO if it is a simple static cursor.
+ */
+- (BOOL) isAnimated;
+
+/** @method     cursorType
+    @abstract   Get the cursor type for this cursor
+    @discussion This method returns the <code>nsCursor</code> constant that corresponds to this cursor, which is  
+                equivalent to the CSS name for the cursor.
+    @result     The nsCursor constant corresponding to this cursor, or nsCursor's 'eCursorCount' if the cursor 
+                is a custom cursor loaded from a URI
+ */
+- (nsCursor) type;
+@end
+
+#endif // nsMacCursor_h_
diff --git a/widget/cocoa/nsMacCursor.mm b/widget/cocoa/nsMacCursor.mm
new file mode 100644
index 0000000000..4fcdfd3e5d
--- /dev/null
+++ b/widget/cocoa/nsMacCursor.mm
@@ -0,0 +1,382 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsMacCursor.h"
+#include "nsObjCExceptions.h"
+#include "nsDebug.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsCOMPtr.h"
+#include "nsIFile.h"
+#include "nsString.h"
+
+/*! @category   nsMacCursor (PrivateMethods)
+    @abstract   Private methods internal to the nsMacCursor class.
+    @discussion <code>nsMacCursor</code> is effectively an abstract class. It does not define complete 
+                behaviour in and of itself, the subclasses defined in this file provide the useful implementations.
+*/
+@interface nsMacCursor (PrivateMethods)
+
+/*! @method     getNextCursorFrame
+    @abstract   get the index of the next cursor frame to display.
+    @discussion Increments and returns the frame counter of an animated cursor.
+    @result     The index of the next frame to display in the cursor animation
+*/
+- (int) getNextCursorFrame;
+
+/*! @method     numFrames
+    @abstract   Query the number of frames in this cursor's animation.
+    @discussion Returns the number of frames in this cursor's animation. Static cursors return 1.
+*/
+- (int) numFrames;
+
+/*! @method     createTimer
+    @abstract   Create a Timer to use to animate the cursor.
+    @discussion Creates an instance of <code>NSTimer</code> which is used to drive the cursor animation.
+                This method should only be called for cursors that are animated.
+*/
+- (void) createTimer;
+
+/*! @method     destroyTimer
+    @abstract   Destroy any timer instance associated with this cursor.
+    @discussion Invalidates and releases any <code>NSTimer</code> instance associated with this cursor.
+ */
+- (void) destroyTimer;
+/*! @method     destroyTimer
+    @abstract   Destroy any timer instance associated with this cursor.
+    @discussion Invalidates and releases any <code>NSTimer</code> instance associated with this cursor.
+*/
+
+/*! @method     advanceAnimatedCursor:
+    @abstract   Method called by animation timer to perform animation.
+    @discussion Called by an animated cursor's associated timer to advance the animation to the next frame.
+                Determines which frame should occur next and sets the cursor to that frame.
+    @param      aTimer the timer causing the animation
+*/
+- (void) advanceAnimatedCursor: (NSTimer *) aTimer;
+
+/*! @method     setFrame:
+    @abstract   Sets the current cursor, using an index to determine which frame in the animation to display.
+    @discussion Sets the current cursor. The frame index determines which frame is shown if the cursor is animated.
+                Frames and numbered from <code>0</code> to <code>-[nsMacCursor numFrames] - 1</code>. A static cursor
+                has a single frame, numbered 0.
+    @param      aFrameIndex the index indicating which frame from the animation to display
+*/
+- (void) setFrame: (int) aFrameIndex;
+
+@end
+
+/*! @class      nsCocoaCursor
+    @abstract   Implementation of <code>nsMacCursor</code> that uses Cocoa <code>NSCursor</code> instances.
+    @discussion Displays a static or animated cursor, using Cocoa <code>NSCursor</code> instances. These can be either
+                built-in <code>NSCursor</code> instances, or custom <code>NSCursor</code>s created from images.
+                When more than one <code>NSCursor</code> is provided, the cursor will use these as animation frames.
+*/
+@interface nsCocoaCursor : nsMacCursor
+{
+  @private
+  NSArray *mFrames;
+  NSCursor *mLastSetCocoaCursor;
+}
+
+/*! @method     initWithFrames:
+    @abstract   Create an animated cursor by specifying the frames to use for the animation.
+    @discussion Creates a cursor that will animate by cycling through the given frames. Each element of the array
+                must be an instance of <code>NSCursor</code>
+    @param      aCursorFrames an array of <code>NSCursor</code>, representing the frames of an animated cursor, in the
+                order they should be played.
+    @param      aType the corresponding <code>nsCursor</code> constant
+    @result     an instance of <code>nsCocoaCursor</code> that will animate the given cursor frames
+ */
+- (id) initWithFrames: (NSArray *) aCursorFrames type: (nsCursor) aType;
+
+/*! @method     initWithCursor:
+    @abstract   Create a cursor by specifying a Cocoa <code>NSCursor</code>.
+    @discussion Creates a cursor representing the given Cocoa built-in cursor.
+    @param      aCursor the <code>NSCursor</code> to use
+    @param      aType the corresponding <code>nsCursor</code> constant
+    @result     an instance of <code>nsCocoaCursor</code> representing the given <code>NSCursor</code>
+*/
+- (id) initWithCursor: (NSCursor *) aCursor type: (nsCursor) aType;
+
+/*! @method     initWithImageNamed:hotSpot:
+    @abstract   Create a cursor by specifying the name of an image resource to use for the cursor and a hotspot.
+    @discussion Creates a cursor by loading the named image using the <code>+[NSImage imageNamed:]</code> method.
+                <p>The image must be compatible with any restrictions laid down by <code>NSCursor</code>. These vary
+                by operating system version.</p>
+                <p>The hotspot precisely determines the point where the user clicks when using the cursor.</p>
+    @param      aCursor the name of the image to use for the cursor
+    @param      aPoint the point within the cursor to use as the hotspot
+    @param      aType the corresponding <code>nsCursor</code> constant
+    @result     an instance of <code>nsCocoaCursor</code> that uses the given image and hotspot
+*/
+- (id) initWithImageNamed: (NSString *) aCursorImage hotSpot: (NSPoint) aPoint type: (nsCursor) aType;
+
+@end
+
+@implementation nsMacCursor
+
++ (nsMacCursor *) cursorWithCursor: (NSCursor *) aCursor type: (nsCursor) aType
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [[[nsCocoaCursor alloc] initWithCursor:aCursor type:aType] autorelease];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
++ (nsMacCursor *) cursorWithImageNamed: (NSString *) aCursorImage hotSpot: (NSPoint) aPoint type: (nsCursor) aType
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [[[nsCocoaCursor alloc] initWithImageNamed:aCursorImage hotSpot:aPoint type:aType] autorelease];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
++ (nsMacCursor *) cursorWithFrames: (NSArray *) aCursorFrames type: (nsCursor) aType
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [[[nsCocoaCursor alloc] initWithFrames:aCursorFrames type:aType] autorelease];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
++ (NSCursor *) cocoaCursorWithImageNamed: (NSString *) imageName hotSpot: (NSPoint) aPoint
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  nsCOMPtr<nsIFile> resDir;
+  nsAutoCString resPath;
+  NSString* pathToImage, *pathToHiDpiImage;
+  NSImage* cursorImage, *hiDpiCursorImage;
+
+  nsresult rv = NS_GetSpecialDirectory(NS_GRE_DIR, getter_AddRefs(resDir));
+  if (NS_FAILED(rv))
+    goto INIT_FAILURE;
+  resDir->AppendNative(NS_LITERAL_CSTRING("res"));
+  resDir->AppendNative(NS_LITERAL_CSTRING("cursors"));
+
+  rv = resDir->GetNativePath(resPath);
+  if (NS_FAILED(rv))
+    goto INIT_FAILURE;
+
+  pathToImage = [NSString stringWithUTF8String:(const char*)resPath.get()];
+  if (!pathToImage)
+    goto INIT_FAILURE;
+  pathToImage = [pathToImage stringByAppendingPathComponent:imageName];
+  pathToHiDpiImage = [pathToImage stringByAppendingString:@"@2x"];
+  // Add same extension to both image paths.
+  pathToImage      = [pathToImage      stringByAppendingPathExtension:@"png"];
+  pathToHiDpiImage = [pathToHiDpiImage stringByAppendingPathExtension:@"png"];
+
+  cursorImage = [[[NSImage alloc] initWithContentsOfFile:pathToImage] autorelease];
+  if (!cursorImage)
+    goto INIT_FAILURE;
+
+  // Note 1: There are a few different ways to get a hidpi image via
+  // initWithContentsOfFile. We let the OS handle this here: when the
+  // file basename ends in "@2x", it will be displayed at native resolution
+  // instead of being pixel-doubled. See bug 784909 comment 7 for alternates ways.
+  //
+  // Note 2: The OS is picky, and will ignore the hidpi representation
+  // unless it is exactly twice the size of the lowdpi image.
+  hiDpiCursorImage = [[[NSImage alloc] initWithContentsOfFile:pathToHiDpiImage] autorelease];
+  if (hiDpiCursorImage) {
+    NSImageRep *imageRep = [[hiDpiCursorImage representations] objectAtIndex:0];
+    [cursorImage addRepresentation: imageRep];
+  }
+  return [[[NSCursor alloc] initWithImage:cursorImage hotSpot:aPoint] autorelease];
+
+INIT_FAILURE:
+  NS_WARNING("Problem getting path to cursor image file!");
+  [self release];
+  return nil;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (BOOL) isSet
+{
+  // implemented by subclasses
+  return NO;
+}
+
+- (void) set
+{
+  if ([self isAnimated]) {
+    [self createTimer];
+  }
+  // if the cursor isn't animated or the timer creation fails for any reason...
+  if (!mTimer) {
+    [self setFrame:0];
+  }
+}
+
+- (void) unset
+{
+  [self destroyTimer];    
+}
+
+- (BOOL) isAnimated
+{
+  return [self numFrames] > 1;
+}
+
+- (int) numFrames
+{
+  // subclasses need to override this to support animation
+  return 1;
+}
+
+- (int) getNextCursorFrame
+{
+  mFrameCounter = (mFrameCounter + 1) % [self numFrames];
+  return mFrameCounter;
+}
+
+- (void) createTimer
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!mTimer) {
+    mTimer = [[NSTimer scheduledTimerWithTimeInterval:0.25
+                                               target:self
+                                             selector:@selector(advanceAnimatedCursor:)
+                                             userInfo:nil
+                                              repeats:YES] retain];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void) destroyTimer
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mTimer) {
+      [mTimer invalidate];
+      [mTimer release];
+      mTimer = nil;
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void) advanceAnimatedCursor: (NSTimer *) aTimer
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if ([aTimer isValid]) {
+    [self setFrame:[self getNextCursorFrame]];
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void) setFrame: (int) aFrameIndex
+{
+  // subclasses need to do something useful here
+}
+
+- (nsCursor) type {
+  return mType;
+}
+
+- (void) dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [self destroyTimer];
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@end
+
+@implementation nsCocoaCursor
+
+- (id) initWithFrames: (NSArray *) aCursorFrames type: (nsCursor) aType
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  self = [super init];
+  NSEnumerator *it = [aCursorFrames objectEnumerator];
+  NSObject *frame = nil;
+  while ((frame = [it nextObject])) {
+    NS_ASSERTION([frame isKindOfClass:[NSCursor class]], "Invalid argument: All frames must be of type NSCursor");
+  }
+  mFrames = [aCursorFrames retain];
+  mFrameCounter = 0;
+  mType = aType;
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (id) initWithCursor: (NSCursor *) aCursor type: (nsCursor) aType
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSArray *frame = [NSArray arrayWithObjects:aCursor, nil];
+  return [self initWithFrames:frame type:aType];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (id) initWithImageNamed: (NSString *) aCursorImage hotSpot: (NSPoint) aPoint type: (nsCursor) aType
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [self initWithCursor:[nsMacCursor cocoaCursorWithImageNamed:aCursorImage hotSpot:aPoint] type:aType];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (BOOL) isSet
+{
+  return [NSCursor currentCursor] == mLastSetCocoaCursor;
+}
+
+- (void) setFrame: (int) aFrameIndex
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NSCursor* newCursor = [mFrames objectAtIndex:aFrameIndex];
+  [newCursor set];
+  mLastSetCocoaCursor = newCursor;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (int) numFrames
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return [mFrames count];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0);
+}
+
+- (NSString *) description
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [mFrames description];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void) dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mFrames release];
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@end
diff --git a/widget/cocoa/nsMacDockSupport.h b/widget/cocoa/nsMacDockSupport.h
new file mode 100644
index 0000000000..a638b89e03
--- /dev/null
+++ b/widget/cocoa/nsMacDockSupport.h
@@ -0,0 +1,41 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIMacDockSupport.h"
+#include "nsIStandaloneNativeMenu.h"
+#include "nsITaskbarProgress.h"
+#include "nsITimer.h"
+#include "nsCOMPtr.h"
+#include "nsString.h"
+#include "nsNativeThemeCocoa.h"
+
+class nsMacDockSupport : public nsIMacDockSupport, public nsITaskbarProgress
+{
+public:
+  nsMacDockSupport();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIMACDOCKSUPPORT
+  NS_DECL_NSITASKBARPROGRESS
+
+protected:
+  virtual ~nsMacDockSupport();
+
+  nsCOMPtr<nsIStandaloneNativeMenu> mDockMenu;
+  nsString mBadgeText;
+
+  NSImage *mAppIcon, *mProgressBackground;
+
+  HIRect mProgressBounds;
+  nsTaskbarProgressState mProgressState;
+  double mProgressFraction;
+  nsCOMPtr<nsITimer> mProgressTimer;
+  RefPtr<nsNativeThemeCocoa> mTheme;
+
+  static void RedrawIconCallback(nsITimer* aTimer, void* aClosure);
+
+  bool InitProgress();
+  nsresult RedrawIcon();
+};
diff --git a/widget/cocoa/nsMacDockSupport.mm b/widget/cocoa/nsMacDockSupport.mm
new file mode 100644
index 0000000000..56b37822bd
--- /dev/null
+++ b/widget/cocoa/nsMacDockSupport.mm
@@ -0,0 +1,174 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsComponentManagerUtils.h"
+#include "nsMacDockSupport.h"
+#include "nsObjCExceptions.h"
+
+NS_IMPL_ISUPPORTS(nsMacDockSupport, nsIMacDockSupport, nsITaskbarProgress)
+
+nsMacDockSupport::nsMacDockSupport()
+: mAppIcon(nil)
+, mProgressBackground(nil)
+, mProgressState(STATE_NO_PROGRESS)
+, mProgressFraction(0.0)
+{
+  mProgressTimer = do_CreateInstance(NS_TIMER_CONTRACTID);
+}
+
+nsMacDockSupport::~nsMacDockSupport()
+{
+  if (mAppIcon) {
+    [mAppIcon release];
+    mAppIcon = nil;
+  }
+  if (mProgressBackground) {
+    [mProgressBackground release];
+    mProgressBackground = nil;
+  }
+  if (mProgressTimer) {
+    mProgressTimer->Cancel();
+    mProgressTimer = nullptr;
+  }
+}
+
+NS_IMETHODIMP
+nsMacDockSupport::GetDockMenu(nsIStandaloneNativeMenu ** aDockMenu)
+{
+  nsCOMPtr<nsIStandaloneNativeMenu> dockMenu(mDockMenu);
+  dockMenu.forget(aDockMenu);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMacDockSupport::SetDockMenu(nsIStandaloneNativeMenu * aDockMenu)
+{
+  mDockMenu = aDockMenu;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMacDockSupport::ActivateApplication(bool aIgnoreOtherApplications)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  [[NSApplication sharedApplication] activateIgnoringOtherApps:aIgnoreOtherApplications];
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsMacDockSupport::SetBadgeText(const nsAString& aBadgeText)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSDockTile *tile = [[NSApplication sharedApplication] dockTile];
+  mBadgeText = aBadgeText;
+  if (aBadgeText.IsEmpty())
+    [tile setBadgeLabel: nil];
+  else
+    [tile setBadgeLabel:[NSString stringWithCharacters:reinterpret_cast<const unichar*>(mBadgeText.get())
+                                                length:mBadgeText.Length()]];
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsMacDockSupport::GetBadgeText(nsAString& aBadgeText)
+{
+  aBadgeText = mBadgeText;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsMacDockSupport::SetProgressState(nsTaskbarProgressState aState,
+                                   uint64_t aCurrentValue,
+                                   uint64_t aMaxValue)
+{
+  NS_ENSURE_ARG_RANGE(aState, 0, STATE_PAUSED);
+  if (aState == STATE_NO_PROGRESS || aState == STATE_INDETERMINATE) {
+    NS_ENSURE_TRUE(aCurrentValue == 0, NS_ERROR_INVALID_ARG);
+    NS_ENSURE_TRUE(aMaxValue == 0, NS_ERROR_INVALID_ARG);
+  }
+  if (aCurrentValue > aMaxValue) {
+    return NS_ERROR_ILLEGAL_VALUE;
+  }
+
+  mProgressState = aState;
+  if (aMaxValue == 0) {
+    mProgressFraction = 0;
+  } else {
+    mProgressFraction = (double)aCurrentValue / aMaxValue;
+  }
+
+  if (mProgressState == STATE_NORMAL || mProgressState == STATE_INDETERMINATE) {
+    int perSecond = 8; // Empirically determined, see bug 848792 
+    mProgressTimer->InitWithFuncCallback(RedrawIconCallback, this, 1000 / perSecond,
+      nsITimer::TYPE_REPEATING_SLACK);
+    return NS_OK;
+  } else {
+    mProgressTimer->Cancel();
+    return RedrawIcon();
+  }
+}
+
+// static
+void nsMacDockSupport::RedrawIconCallback(nsITimer* aTimer, void* aClosure)
+{
+  static_cast<nsMacDockSupport*>(aClosure)->RedrawIcon();
+}
+
+// Return whether to draw progress
+bool nsMacDockSupport::InitProgress()
+{
+  if (mProgressState != STATE_NORMAL && mProgressState != STATE_INDETERMINATE) {
+    return false;
+  }
+
+  if (!mAppIcon) {
+    mProgressTimer = do_CreateInstance(NS_TIMER_CONTRACTID);
+    mAppIcon = [[NSImage imageNamed:@"NSApplicationIcon"] retain];
+    mProgressBackground = [mAppIcon copyWithZone:nil];
+    mTheme = new nsNativeThemeCocoa();
+
+    NSSize sz = [mProgressBackground size];
+    mProgressBounds = CGRectMake(sz.width * 1/32, sz.height * 3/32,
+                                 sz.width * 30/32, sz.height * 4/32);
+    [mProgressBackground lockFocus];
+    [[NSColor whiteColor] set];
+    NSRectFill(NSRectFromCGRect(mProgressBounds));
+    [mProgressBackground unlockFocus];
+  }
+  return true;
+}
+
+nsresult
+nsMacDockSupport::RedrawIcon()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (InitProgress()) {
+    // TODO: - Implement ERROR and PAUSED states?
+    NSImage *icon = [mProgressBackground copyWithZone:nil];
+    bool isIndeterminate = (mProgressState != STATE_NORMAL);
+
+    [icon lockFocus];
+    CGContextRef ctx = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
+    mTheme->DrawProgress(ctx, mProgressBounds, isIndeterminate,
+      true, mProgressFraction, 1.0, NULL);
+    [icon unlockFocus];
+    [NSApp setApplicationIconImage:icon];
+    [icon release];
+  } else {
+    [NSApp setApplicationIconImage:mAppIcon];
+  }
+
+  return NS_OK;
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
diff --git a/widget/cocoa/nsMacWebAppUtils.h b/widget/cocoa/nsMacWebAppUtils.h
new file mode 100644
index 0000000000..98ef235615
--- /dev/null
+++ b/widget/cocoa/nsMacWebAppUtils.h
@@ -0,0 +1,22 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef _MAC_WEB_APP_UTILS_H_
+#define _MAC_WEB_APP_UTILS_H_
+
+#include "nsIMacWebAppUtils.h"
+
+#define NS_MACWEBAPPUTILS_CONTRACTID "@mozilla.org/widget/mac-web-app-utils;1"
+
+class nsMacWebAppUtils : public nsIMacWebAppUtils {
+public:
+  nsMacWebAppUtils() {}
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIMACWEBAPPUTILS
+
+protected:
+  virtual ~nsMacWebAppUtils() {}
+};
+
+#endif //_MAC_WEB_APP_UTILS_H_
diff --git a/widget/cocoa/nsMacWebAppUtils.mm b/widget/cocoa/nsMacWebAppUtils.mm
new file mode 100644
index 0000000000..1b98cef7cc
--- /dev/null
+++ b/widget/cocoa/nsMacWebAppUtils.mm
@@ -0,0 +1,82 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsMacWebAppUtils.h"
+#include "nsCOMPtr.h"
+#include "nsCocoaUtils.h"
+#include "nsString.h"
+
+// This must be included last:
+#include "nsObjCExceptions.h"
+
+// Find the path to the app with the given bundleIdentifier, if any.
+// Note that the OS will return the path to the newest binary, if there is more than one.
+// The determination of 'newest' is complex and beyond the scope of this comment.
+
+NS_IMPL_ISUPPORTS(nsMacWebAppUtils, nsIMacWebAppUtils)
+
+NS_IMETHODIMP nsMacWebAppUtils::PathForAppWithIdentifier(const nsAString& bundleIdentifier, nsAString& outPath) {
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  outPath.Truncate();
+
+  nsAutoreleasePool localPool;
+
+  //note that the result of this expression might be nil, meaning no matching app was found. 
+  NSString* temp = [[NSWorkspace sharedWorkspace] absolutePathForAppBundleWithIdentifier:
+                        [NSString stringWithCharacters:reinterpret_cast<const unichar*>(((nsString)bundleIdentifier).get())
+                                                length:((nsString)bundleIdentifier).Length()]];
+
+  if (temp) {
+    // Copy out the resultant absolute path into outPath if non-nil.
+    nsCocoaUtils::GetStringForNSString(temp, outPath);
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsMacWebAppUtils::LaunchAppWithIdentifier(const nsAString& bundleIdentifier) {
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  nsAutoreleasePool localPool;
+
+  // Note this might return false, meaning the app wasnt launched for some reason. 
+  BOOL success = [[NSWorkspace sharedWorkspace] launchAppWithBundleIdentifier:
+                        [NSString stringWithCharacters:reinterpret_cast<const unichar*>(((nsString)bundleIdentifier).get())
+                                                length:((nsString)bundleIdentifier).Length()]
+                        options: (NSWorkspaceLaunchOptions)0
+                        additionalEventParamDescriptor: nil
+                        launchIdentifier: NULL];
+
+  return success ? NS_OK : NS_ERROR_FAILURE;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsMacWebAppUtils::TrashApp(const nsAString& path, nsITrashAppCallback* aCallback) {
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (NS_WARN_IF(!aCallback)) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  nsCOMPtr<nsITrashAppCallback> callback = aCallback;
+
+  NSString* tempString = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(((nsString)path).get())
+                                   length:path.Length()];
+
+  [[NSWorkspace sharedWorkspace] recycleURLs: [NSArray arrayWithObject:[NSURL fileURLWithPath:tempString]]
+    completionHandler: ^(NSDictionary *newURLs, NSError *error) {
+      nsresult rv = (error == nil) ? NS_OK : NS_ERROR_FAILURE;
+      callback->TrashAppFinished(rv);
+    }];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
diff --git a/widget/cocoa/nsMenuBarX.h b/widget/cocoa/nsMenuBarX.h
new file mode 100644
index 0000000000..7cbb8ce62a
--- /dev/null
+++ b/widget/cocoa/nsMenuBarX.h
@@ -0,0 +1,128 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsMenuBarX_h_
+#define nsMenuBarX_h_
+
+#import <Cocoa/Cocoa.h>
+
+#include "mozilla/UniquePtr.h"
+#include "nsMenuBaseX.h"
+#include "nsMenuGroupOwnerX.h"
+#include "nsChangeObserver.h"
+#include "nsINativeMenuService.h"
+#include "nsString.h"
+
+class nsMenuX;
+class nsIWidget;
+class nsIContent;
+
+// The native menu service for creating native menu bars.
+class nsNativeMenuServiceX : public nsINativeMenuService
+{
+public:
+  NS_DECL_ISUPPORTS
+
+  nsNativeMenuServiceX() {}
+
+  NS_IMETHOD CreateNativeMenuBar(nsIWidget* aParent, nsIContent* aMenuBarNode) override;
+
+protected:
+  virtual ~nsNativeMenuServiceX() {}
+};
+
+// Objective-C class used to allow us to intervene with keyboard event handling.
+// We allow mouse actions to work normally.
+@interface GeckoNSMenu : NSMenu
+{
+}
+@end
+
+// Objective-C class used as action target for menu items
+@interface NativeMenuItemTarget : NSObject
+{
+}
+-(IBAction)menuItemHit:(id)sender;
+@end
+
+// Objective-C class used for menu items on the Services menu to allow Gecko
+// to override their standard behavior in order to stop key equivalents from
+// firing in certain instances.
+@interface GeckoServicesNSMenuItem : NSMenuItem
+{
+}
+- (id) target;
+- (SEL) action;
+- (void) _doNothing:(id)sender;
+@end
+
+// Objective-C class used as the Services menu so that Gecko can override the
+// standard behavior of the Services menu in order to stop key equivalents
+// from firing in certain instances.
+@interface GeckoServicesNSMenu : NSMenu
+{
+}
+- (void)addItem:(NSMenuItem *)newItem;
+- (NSMenuItem *)addItemWithTitle:(NSString *)aString action:(SEL)aSelector keyEquivalent:(NSString *)keyEquiv;
+- (void)insertItem:(NSMenuItem *)newItem atIndex:(NSInteger)index;
+- (NSMenuItem *)insertItemWithTitle:(NSString *)aString action:(SEL)aSelector  keyEquivalent:(NSString *)keyEquiv atIndex:(NSInteger)index;
+- (void) _overrideClassOfMenuItem:(NSMenuItem *)menuItem;
+@end
+
+// Once instantiated, this object lives until its DOM node or its parent window is destroyed.
+// Do not hold references to this, they can become invalid any time the DOM node can be destroyed.
+class nsMenuBarX : public nsMenuGroupOwnerX, public nsChangeObserver
+{
+public:
+  nsMenuBarX();
+  virtual ~nsMenuBarX();
+
+  static NativeMenuItemTarget* sNativeEventTarget;
+  static nsMenuBarX*           sLastGeckoMenuBarPainted;
+
+  // The following content nodes have been removed from the menu system.
+  // We save them here for use in command handling.
+  nsCOMPtr<nsIContent> mAboutItemContent;
+  nsCOMPtr<nsIContent> mPrefItemContent;
+  nsCOMPtr<nsIContent> mQuitItemContent;
+
+  // nsChangeObserver
+  NS_DECL_CHANGEOBSERVER
+
+  // nsMenuObjectX
+  void*             NativeData() override {return (void*)mNativeMenu;}
+  nsMenuObjectTypeX MenuObjectType() override {return eMenuBarObjectType;}
+
+  // nsMenuBarX
+  nsresult          Create(nsIWidget* aParent, nsIContent* aContent);
+  void              SetParent(nsIWidget* aParent);
+  uint32_t          GetMenuCount();
+  bool              MenuContainsAppMenu();
+  nsMenuX*          GetMenuAt(uint32_t aIndex);
+  nsMenuX*          GetXULHelpMenu();
+  void              SetSystemHelpMenu();
+  nsresult          Paint();
+  void              ForceUpdateNativeMenuAt(const nsAString& indexString);
+  void              ForceNativeMenuReload(); // used for testing
+  static char       GetLocalizedAccelKey(const char *shortcutID);
+  static void       ResetNativeApplicationMenu();
+
+protected:
+  void              ConstructNativeMenus();
+  void              ConstructFallbackNativeMenus();
+  nsresult          InsertMenuAtIndex(nsMenuX* aMenu, uint32_t aIndex);
+  void              RemoveMenuAtIndex(uint32_t aIndex);
+  void              HideItem(nsIDOMDocument* inDoc, const nsAString & inID, nsIContent** outHiddenNode);
+  void              AquifyMenuBar();
+  NSMenuItem*       CreateNativeAppMenuItem(nsMenuX* inMenu, const nsAString& nodeID, SEL action,
+                                            int tag, NativeMenuItemTarget* target);
+  nsresult          CreateApplicationMenu(nsMenuX* inMenu);
+
+  nsTArray<mozilla::UniquePtr<nsMenuX>> mMenuArray;
+  nsIWidget*         mParentWindow;        // [weak]
+  GeckoNSMenu*       mNativeMenu;            // root menu, representing entire menu bar
+};
+
+#endif // nsMenuBarX_h_
diff --git a/widget/cocoa/nsMenuBarX.mm b/widget/cocoa/nsMenuBarX.mm
new file mode 100644
index 0000000000..ff25eb81fc
--- /dev/null
+++ b/widget/cocoa/nsMenuBarX.mm
@@ -0,0 +1,979 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <objc/objc-runtime.h>
+
+#include "nsMenuBarX.h"
+#include "nsMenuX.h"
+#include "nsMenuItemX.h"
+#include "nsMenuUtilsX.h"
+#include "nsCocoaUtils.h"
+#include "nsCocoaWindow.h"
+#include "nsChildView.h"
+
+#include "nsCOMPtr.h"
+#include "nsString.h"
+#include "nsGkAtoms.h"
+#include "nsObjCExceptions.h"
+#include "nsThreadUtils.h"
+
+#include "nsIContent.h"
+#include "nsIWidget.h"
+#include "nsIDocument.h"
+#include "nsIDOMDocument.h"
+#include "nsIDOMElement.h"
+#include "nsIAppStartup.h"
+#include "nsIStringBundle.h"
+#include "nsToolkitCompsCID.h"
+
+NativeMenuItemTarget* nsMenuBarX::sNativeEventTarget = nil;
+nsMenuBarX* nsMenuBarX::sLastGeckoMenuBarPainted = nullptr;
+NSMenu* sApplicationMenu = nil;
+BOOL sApplicationMenuIsFallback = NO;
+BOOL gSomeMenuBarPainted = NO;
+
+// We keep references to the first quit and pref item content nodes we find, which
+// will be from the hidden window. We use these when the document for the current
+// window does not have a quit or pref item. We don't need strong refs here because
+// these items are always strong ref'd by their owning menu bar (instance variable).
+static nsIContent* sAboutItemContent  = nullptr;
+static nsIContent* sPrefItemContent   = nullptr;
+static nsIContent* sQuitItemContent   = nullptr;
+
+NS_IMPL_ISUPPORTS(nsNativeMenuServiceX, nsINativeMenuService)
+
+NS_IMETHODIMP nsNativeMenuServiceX::CreateNativeMenuBar(nsIWidget* aParent, nsIContent* aMenuBarNode)
+{
+  NS_ASSERTION(NS_IsMainThread(), "Attempting to create native menu bar on wrong thread!");
+
+  RefPtr<nsMenuBarX> mb = new nsMenuBarX();
+  if (!mb)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  return mb->Create(aParent, aMenuBarNode);
+}
+
+nsMenuBarX::nsMenuBarX()
+: nsMenuGroupOwnerX(), mParentWindow(nullptr)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  mNativeMenu = [[GeckoNSMenu alloc] initWithTitle:@"MainMenuBar"];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsMenuBarX::~nsMenuBarX()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (nsMenuBarX::sLastGeckoMenuBarPainted == this)
+    nsMenuBarX::sLastGeckoMenuBarPainted = nullptr;
+
+  // the quit/pref items of a random window might have been used if there was no
+  // hidden window, thus we need to invalidate the weak references.
+  if (sAboutItemContent == mAboutItemContent)
+    sAboutItemContent = nullptr;
+  if (sQuitItemContent == mQuitItemContent)
+    sQuitItemContent = nullptr;
+  if (sPrefItemContent == mPrefItemContent)
+    sPrefItemContent = nullptr;
+
+  // make sure we unregister ourselves as a content observer
+  if (mContent) {
+    UnregisterForContentChanges(mContent);
+  }
+
+  // We have to manually clear the array here because clearing causes menu items
+  // to call back into the menu bar to unregister themselves. We don't want to
+  // depend on member variable ordering to ensure that the array gets cleared
+  // before the registration hash table is destroyed.
+  mMenuArray.Clear();
+
+  [mNativeMenu release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsresult nsMenuBarX::Create(nsIWidget* aParent, nsIContent* aContent)
+{
+  if (!aParent)
+    return NS_ERROR_INVALID_ARG;
+
+  mParentWindow = aParent;
+  mContent = aContent;
+
+  if (mContent) {
+    AquifyMenuBar();
+
+    nsresult rv = nsMenuGroupOwnerX::Create(mContent);
+    if (NS_FAILED(rv))
+      return rv;
+
+    RegisterForContentChanges(mContent, this);
+    ConstructNativeMenus();
+  } else {
+    ConstructFallbackNativeMenus();
+  }
+
+  // Give this to the parent window. The parent takes ownership.
+  static_cast<nsCocoaWindow*>(mParentWindow)->SetMenuBar(this);
+
+  return NS_OK;
+}
+
+void nsMenuBarX::ConstructNativeMenus()
+{
+  uint32_t count = mContent->GetChildCount();
+  for (uint32_t i = 0; i < count; i++) {
+    nsIContent *menuContent = mContent->GetChildAt(i);
+    if (menuContent &&
+        menuContent->IsXULElement(nsGkAtoms::menu)) {
+      nsMenuX* newMenu = new nsMenuX();
+      if (newMenu) {
+        nsresult rv = newMenu->Create(this, this, menuContent);
+        if (NS_SUCCEEDED(rv))
+          InsertMenuAtIndex(newMenu, GetMenuCount());
+        else
+          delete newMenu;
+      }
+    }
+  }
+}
+
+void nsMenuBarX::ConstructFallbackNativeMenus()
+{
+  if (sApplicationMenu) {
+    // Menu has already been built.
+    return;
+  }
+
+  nsCOMPtr<nsIStringBundle> stringBundle;
+
+  nsCOMPtr<nsIStringBundleService> bundleSvc = do_GetService(NS_STRINGBUNDLE_CONTRACTID);
+  bundleSvc->CreateBundle("chrome://global/locale/fallbackMenubar.properties", getter_AddRefs(stringBundle));
+
+  if (!stringBundle) {
+    return;
+  }
+
+  nsXPIDLString labelUTF16;
+  nsXPIDLString keyUTF16;
+
+  const char16_t* labelProp = u"quitMenuitem.label";
+  const char16_t* keyProp = u"quitMenuitem.key";
+
+  stringBundle->GetStringFromName(labelProp, getter_Copies(labelUTF16));
+  stringBundle->GetStringFromName(keyProp, getter_Copies(keyUTF16));
+
+  NSString* labelStr = [NSString stringWithUTF8String:
+                        NS_ConvertUTF16toUTF8(labelUTF16).get()];
+  NSString* keyStr= [NSString stringWithUTF8String:
+                     NS_ConvertUTF16toUTF8(keyUTF16).get()];
+
+  if (!nsMenuBarX::sNativeEventTarget) {
+    nsMenuBarX::sNativeEventTarget = [[NativeMenuItemTarget alloc] init];
+  }
+
+  sApplicationMenu = [[[[NSApp mainMenu] itemAtIndex:0] submenu] retain];
+  NSMenuItem* quitMenuItem = [[[NSMenuItem alloc] initWithTitle:labelStr
+                                                  action:@selector(menuItemHit:)
+                                                  keyEquivalent:keyStr] autorelease];
+  [quitMenuItem setTarget:nsMenuBarX::sNativeEventTarget];
+  [quitMenuItem setTag:eCommand_ID_Quit];
+  [sApplicationMenu addItem:quitMenuItem];
+  sApplicationMenuIsFallback = YES;
+}
+
+uint32_t nsMenuBarX::GetMenuCount()
+{
+  return mMenuArray.Length();
+}
+
+bool nsMenuBarX::MenuContainsAppMenu()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return ([mNativeMenu numberOfItems] > 0 &&
+          [[mNativeMenu itemAtIndex:0] submenu] == sApplicationMenu);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+nsresult nsMenuBarX::InsertMenuAtIndex(nsMenuX* aMenu, uint32_t aIndex)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // If we've only yet created a fallback global Application menu (using
+  // ContructFallbackNativeMenus()), destroy it before recreating it properly.
+  if (sApplicationMenu && sApplicationMenuIsFallback) {
+    ResetNativeApplicationMenu();
+  }
+  // If we haven't created a global Application menu yet, do it.
+  if (!sApplicationMenu) {
+    nsresult rv = NS_OK; // avoid warning about rv being unused
+    rv = CreateApplicationMenu(aMenu);
+    NS_ASSERTION(NS_SUCCEEDED(rv), "Can't create Application menu");
+
+    // Hook the new Application menu up to the menu bar.
+    NSMenu* mainMenu = [NSApp mainMenu];
+    NS_ASSERTION([mainMenu numberOfItems] > 0, "Main menu does not have any items, something is terribly wrong!");
+    [[mainMenu itemAtIndex:0] setSubmenu:sApplicationMenu];
+  }
+
+  // add menu to array that owns our menus
+  mMenuArray.InsertElementAt(aIndex, aMenu);
+
+  // hook up submenus
+  nsIContent* menuContent = aMenu->Content();
+  if (menuContent->GetChildCount() > 0 &&
+      !nsMenuUtilsX::NodeIsHiddenOrCollapsed(menuContent)) {
+    int insertionIndex = nsMenuUtilsX::CalculateNativeInsertionPoint(this, aMenu);
+    if (MenuContainsAppMenu())
+      insertionIndex++;
+    [mNativeMenu insertItem:aMenu->NativeMenuItem() atIndex:insertionIndex];
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void nsMenuBarX::RemoveMenuAtIndex(uint32_t aIndex)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mMenuArray.Length() <= aIndex) {
+    NS_ERROR("Attempting submenu removal with bad index!");
+    return;
+  }
+
+  // Our native menu and our internal menu object array might be out of sync.
+  // This happens, for example, when a submenu is hidden. Because of this we
+  // should not assume that a native submenu is hooked up.
+  NSMenuItem* nativeMenuItem = mMenuArray[aIndex]->NativeMenuItem();
+  int nativeMenuItemIndex = [mNativeMenu indexOfItem:nativeMenuItem];
+  if (nativeMenuItemIndex != -1)
+    [mNativeMenu removeItemAtIndex:nativeMenuItemIndex];
+
+  mMenuArray.RemoveElementAt(aIndex);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsMenuBarX::ObserveAttributeChanged(nsIDocument* aDocument,
+                                         nsIContent* aContent,
+                                         nsIAtom* aAttribute)
+{
+}
+
+void nsMenuBarX::ObserveContentRemoved(nsIDocument* aDocument,
+                                       nsIContent* aChild,
+                                       int32_t aIndexInContainer)
+{
+  RemoveMenuAtIndex(aIndexInContainer);
+}
+
+void nsMenuBarX::ObserveContentInserted(nsIDocument* aDocument,
+                                        nsIContent* aContainer,
+                                        nsIContent* aChild)
+{
+  nsMenuX* newMenu = new nsMenuX();
+  if (newMenu) {
+    nsresult rv = newMenu->Create(this, this, aChild);
+    if (NS_SUCCEEDED(rv))
+      InsertMenuAtIndex(newMenu, aContainer->IndexOf(aChild));
+    else
+      delete newMenu;
+  }
+}
+
+void nsMenuBarX::ForceUpdateNativeMenuAt(const nsAString& indexString)
+{
+  NSString* locationString = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(indexString.BeginReading())
+                                                     length:indexString.Length()];
+  NSArray* indexes = [locationString componentsSeparatedByString:@"|"];
+  unsigned int indexCount = [indexes count];
+  if (indexCount == 0)
+    return;
+
+  nsMenuX* currentMenu = NULL;
+  int targetIndex = [[indexes objectAtIndex:0] intValue];
+  int visible = 0;
+  uint32_t length = mMenuArray.Length();
+  // first find a menu in the menu bar
+  for (unsigned int i = 0; i < length; i++) {
+    nsMenuX* menu = mMenuArray[i].get();
+    if (!nsMenuUtilsX::NodeIsHiddenOrCollapsed(menu->Content())) {
+      visible++;
+      if (visible == (targetIndex + 1)) {
+        currentMenu = menu;
+        break;
+      }
+    }
+  }
+
+  if (!currentMenu)
+    return;
+
+  // fake open/close to cause lazy update to happen so submenus populate
+  currentMenu->MenuOpened();
+  currentMenu->MenuClosed();
+
+  // now find the correct submenu
+  for (unsigned int i = 1; currentMenu && i < indexCount; i++) {
+    targetIndex = [[indexes objectAtIndex:i] intValue];
+    visible = 0;
+    length = currentMenu->GetItemCount();
+    for (unsigned int j = 0; j < length; j++) {
+      nsMenuObjectX* targetMenu = currentMenu->GetItemAt(j);
+      if (!targetMenu)
+        return;
+      if (!nsMenuUtilsX::NodeIsHiddenOrCollapsed(targetMenu->Content())) {
+        visible++;
+        if (targetMenu->MenuObjectType() == eSubmenuObjectType && visible == (targetIndex + 1)) {
+          currentMenu = static_cast<nsMenuX*>(targetMenu);
+          // fake open/close to cause lazy update to happen
+          currentMenu->MenuOpened();
+          currentMenu->MenuClosed();
+          break;
+        }
+      }
+    }
+  }
+}
+
+// Calling this forces a full reload of the menu system, reloading all native
+// menus and their items.
+// Without this testing is hard because changes to the DOM affect the native
+// menu system lazily.
+void nsMenuBarX::ForceNativeMenuReload()
+{
+  // tear down everything
+  while (GetMenuCount() > 0)
+    RemoveMenuAtIndex(0);
+
+  // construct everything
+  ConstructNativeMenus();
+}
+
+nsMenuX* nsMenuBarX::GetMenuAt(uint32_t aIndex)
+{
+  if (mMenuArray.Length() <= aIndex) {
+    NS_ERROR("Requesting menu at invalid index!");
+    return NULL;
+  }
+  return mMenuArray[aIndex].get();
+}
+
+nsMenuX* nsMenuBarX::GetXULHelpMenu()
+{
+  // The Help menu is usually (always?) the last one, so we start there and
+  // count back.
+  for (int32_t i = GetMenuCount() - 1; i >= 0; --i) {
+    nsMenuX* aMenu = GetMenuAt(i);
+    if (aMenu && nsMenuX::IsXULHelpMenu(aMenu->Content()))
+      return aMenu;
+  }
+  return nil;
+}
+
+// On SnowLeopard and later we must tell the OS which is our Help menu.
+// Otherwise it will only add Spotlight for Help (the Search item) to our
+// Help menu if its label/title is "Help" -- i.e. if the menu is in English.
+// This resolves bugs 489196 and 539317.
+void nsMenuBarX::SetSystemHelpMenu()
+{
+  nsMenuX* xulHelpMenu = GetXULHelpMenu();
+  if (xulHelpMenu) {
+    NSMenu* helpMenu = (NSMenu*)xulHelpMenu->NativeData();
+    if (helpMenu)
+      [NSApp setHelpMenu:helpMenu];
+  }
+}
+
+nsresult nsMenuBarX::Paint()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // Don't try to optimize anything in this painting by checking
+  // sLastGeckoMenuBarPainted because the menubar can be manipulated by
+  // native dialogs and sheet code and other things besides this paint method.
+
+  // We have to keep the same menu item for the Application menu so we keep
+  // passing it along.
+  NSMenu* outgoingMenu = [NSApp mainMenu];
+  NS_ASSERTION([outgoingMenu numberOfItems] > 0, "Main menu does not have any items, something is terribly wrong!");
+
+  NSMenuItem* appMenuItem = [[outgoingMenu itemAtIndex:0] retain];
+  [outgoingMenu removeItemAtIndex:0];
+  [mNativeMenu insertItem:appMenuItem atIndex:0];
+  [appMenuItem release];
+
+  // Set menu bar and event target.
+  [NSApp setMainMenu:mNativeMenu];
+  SetSystemHelpMenu();
+  nsMenuBarX::sLastGeckoMenuBarPainted = this;
+
+  gSomeMenuBarPainted = YES;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Returns the 'key' attribute of the 'shortcutID' object (if any) in the
+// currently active menubar's DOM document.  'shortcutID' should be the id
+// (i.e. the name) of a component that defines a commonly used (and
+// localized) cmd+key shortcut, and belongs to a keyset containing similar
+// objects.  For example "key_selectAll".  Returns a value that can be
+// compared to the first character of [NSEvent charactersIgnoringModifiers]
+// when [NSEvent modifierFlags] == NSCommandKeyMask.
+char nsMenuBarX::GetLocalizedAccelKey(const char *shortcutID)
+{
+  if (!sLastGeckoMenuBarPainted)
+    return 0;
+
+  nsCOMPtr<nsIDOMDocument> domDoc(do_QueryInterface(sLastGeckoMenuBarPainted->mContent->OwnerDoc()));
+  if (!domDoc)
+    return 0;
+
+  NS_ConvertASCIItoUTF16 shortcutIDStr((const char *)shortcutID);
+  nsCOMPtr<nsIDOMElement> shortcutElement;
+  domDoc->GetElementById(shortcutIDStr, getter_AddRefs(shortcutElement));
+  nsCOMPtr<nsIContent> shortcutContent = do_QueryInterface(shortcutElement);
+  if (!shortcutContent)
+    return 0;
+
+  nsAutoString key;
+  shortcutContent->GetAttr(kNameSpaceID_None, nsGkAtoms::key, key);
+  NS_LossyConvertUTF16toASCII keyASC(key.get());
+  const char *keyASCPtr = keyASC.get();
+  if (!keyASCPtr)
+    return 0;
+  // If keyID's 'key' attribute isn't exactly one character long, it's not
+  // what we're looking for.
+  if (strlen(keyASCPtr) != sizeof(char))
+    return 0;
+  // Make sure retval is lower case.
+  char retval = tolower(keyASCPtr[0]);
+
+  return retval;
+}
+
+/* static */
+void nsMenuBarX::ResetNativeApplicationMenu()
+{
+  [sApplicationMenu removeAllItems];
+  [sApplicationMenu release];
+  sApplicationMenu = nil;
+  sApplicationMenuIsFallback = NO;
+}
+
+// Hide the item in the menu by setting the 'hidden' attribute. Returns it in |outHiddenNode| so
+// the caller can hang onto it if they so choose. It is acceptable to pass nsull
+// for |outHiddenNode| if the caller doesn't care about the hidden node.
+void nsMenuBarX::HideItem(nsIDOMDocument* inDoc, const nsAString & inID, nsIContent** outHiddenNode)
+{
+  nsCOMPtr<nsIDOMElement> menuItem;
+  inDoc->GetElementById(inID, getter_AddRefs(menuItem));
+  nsCOMPtr<nsIContent> menuContent(do_QueryInterface(menuItem));
+  if (menuContent) {
+    menuContent->SetAttr(kNameSpaceID_None, nsGkAtoms::hidden, NS_LITERAL_STRING("true"), false);
+    if (outHiddenNode) {
+      *outHiddenNode = menuContent.get();
+      NS_IF_ADDREF(*outHiddenNode);
+    }
+  }
+}
+
+// Do what is necessary to conform to the Aqua guidelines for menus.
+void nsMenuBarX::AquifyMenuBar()
+{
+  nsCOMPtr<nsIDOMDocument> domDoc(do_QueryInterface(mContent->GetComposedDoc()));
+  if (domDoc) {
+    // remove the "About..." item and its separator
+    HideItem(domDoc, NS_LITERAL_STRING("aboutSeparator"), nullptr);
+    HideItem(domDoc, NS_LITERAL_STRING("aboutName"), getter_AddRefs(mAboutItemContent));
+    if (!sAboutItemContent)
+      sAboutItemContent = mAboutItemContent;
+
+    // remove quit item and its separator
+    HideItem(domDoc, NS_LITERAL_STRING("menu_FileQuitSeparator"), nullptr);
+    HideItem(domDoc, NS_LITERAL_STRING("menu_FileQuitItem"), getter_AddRefs(mQuitItemContent));
+    if (!sQuitItemContent)
+      sQuitItemContent = mQuitItemContent;
+
+    // remove prefs item and its separator, but save off the pref content node
+    // so we can invoke its command later.
+    HideItem(domDoc, NS_LITERAL_STRING("menu_PrefsSeparator"), nullptr);
+    HideItem(domDoc, NS_LITERAL_STRING("menu_preferences"), getter_AddRefs(mPrefItemContent));
+    if (!sPrefItemContent)
+      sPrefItemContent = mPrefItemContent;
+
+    // hide items that we use for the Application menu
+    HideItem(domDoc, NS_LITERAL_STRING("menu_mac_services"), nullptr);
+    HideItem(domDoc, NS_LITERAL_STRING("menu_mac_hide_app"), nullptr);
+    HideItem(domDoc, NS_LITERAL_STRING("menu_mac_hide_others"), nullptr);
+    HideItem(domDoc, NS_LITERAL_STRING("menu_mac_show_all"), nullptr);
+  }
+}
+
+// for creating menu items destined for the Application menu
+NSMenuItem* nsMenuBarX::CreateNativeAppMenuItem(nsMenuX* inMenu, const nsAString& nodeID, SEL action,
+                                                int tag, NativeMenuItemTarget* target)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  nsCOMPtr<nsIDocument> doc = inMenu->Content()->GetUncomposedDoc();
+  if (!doc) {
+    return nil;
+  }
+
+  nsCOMPtr<nsIDOMDocument> domdoc(do_QueryInterface(doc));
+  if (!domdoc) {
+    return nil;
+  }
+
+  // Get information from the gecko menu item
+  nsAutoString label;
+  nsAutoString modifiers;
+  nsAutoString key;
+  nsCOMPtr<nsIDOMElement> menuItem;
+  domdoc->GetElementById(nodeID, getter_AddRefs(menuItem));
+  if (menuItem) {
+    menuItem->GetAttribute(NS_LITERAL_STRING("label"), label);
+    menuItem->GetAttribute(NS_LITERAL_STRING("modifiers"), modifiers);
+    menuItem->GetAttribute(NS_LITERAL_STRING("key"), key);
+  }
+  else {
+    return nil;
+  }
+
+  // Get more information about the key equivalent. Start by
+  // finding the key node we need.
+  NSString* keyEquiv = nil;
+  unsigned int macKeyModifiers = 0;
+  if (!key.IsEmpty()) {
+    nsCOMPtr<nsIDOMElement> keyElement;
+    domdoc->GetElementById(key, getter_AddRefs(keyElement));
+    if (keyElement) {
+      nsCOMPtr<nsIContent> keyContent (do_QueryInterface(keyElement));
+      // first grab the key equivalent character
+      nsAutoString keyChar(NS_LITERAL_STRING(" "));
+      keyContent->GetAttr(kNameSpaceID_None, nsGkAtoms::key, keyChar);
+      if (!keyChar.EqualsLiteral(" ")) {
+        keyEquiv = [[NSString stringWithCharacters:reinterpret_cast<const unichar*>(keyChar.get())
+                                            length:keyChar.Length()] lowercaseString];
+      }
+      // now grab the key equivalent modifiers
+      nsAutoString modifiersStr;
+      keyContent->GetAttr(kNameSpaceID_None, nsGkAtoms::modifiers, modifiersStr);
+      uint8_t geckoModifiers = nsMenuUtilsX::GeckoModifiersForNodeAttribute(modifiersStr);
+      macKeyModifiers = nsMenuUtilsX::MacModifiersForGeckoModifiers(geckoModifiers);
+    }
+  }
+  // get the label into NSString-form
+  NSString* labelString = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(label.get())
+                                                  length:label.Length()];
+
+  if (!labelString)
+    labelString = @"";
+  if (!keyEquiv)
+    keyEquiv = @"";
+
+  // put together the actual NSMenuItem
+  NSMenuItem* newMenuItem = [[NSMenuItem alloc] initWithTitle:labelString action:action keyEquivalent:keyEquiv];
+
+  [newMenuItem setTag:tag];
+  [newMenuItem setTarget:target];
+  [newMenuItem setKeyEquivalentModifierMask:macKeyModifiers];
+
+  MenuItemInfo * info = [[MenuItemInfo alloc] initWithMenuGroupOwner:this];
+  [newMenuItem setRepresentedObject:info];
+  [info release];
+
+  return newMenuItem;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+// build the Application menu shared by all menu bars
+nsresult nsMenuBarX::CreateApplicationMenu(nsMenuX* inMenu)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // At this point, the application menu is the application menu from
+  // the nib in cocoa widgets. We do not have a way to create an application
+  // menu manually, so we grab the one from the nib and use that.
+  sApplicationMenu = [[[[NSApp mainMenu] itemAtIndex:0] submenu] retain];
+
+/*
+  We support the following menu items here:
+
+  Menu Item                DOM Node ID             Notes
+
+  ========================
+  = About This App       = <- aboutName
+  ========================
+  = Preferences...       = <- menu_preferences
+  ========================
+  = Services     >       = <- menu_mac_services    <- (do not define key equivalent)
+  ========================
+  = Hide App             = <- menu_mac_hide_app
+  = Hide Others          = <- menu_mac_hide_others
+  = Show All             = <- menu_mac_show_all
+  ========================
+  = Quit                 = <- menu_FileQuitItem
+  ========================
+
+  If any of them are ommitted from the application's DOM, we just don't add
+  them. We always add a "Quit" item, but if an app developer does not provide a
+  DOM node with the right ID for the Quit item, we add it in English. App
+  developers need only add each node with a label and a key equivalent (if they
+  want one). Other attributes are optional. Like so:
+
+  <menuitem id="menu_preferences"
+         label="&preferencesCmdMac.label;"
+           key="open_prefs_key"/>
+
+  We need to use this system for localization purposes, until we have a better way
+  to define the Application menu to be used on Mac OS X.
+*/
+
+  if (sApplicationMenu) {
+    // This code reads attributes we are going to care about from the DOM elements
+
+    NSMenuItem *itemBeingAdded = nil;
+    BOOL addAboutSeparator = FALSE;
+
+    // Add the About menu item
+    itemBeingAdded = CreateNativeAppMenuItem(inMenu, NS_LITERAL_STRING("aboutName"), @selector(menuItemHit:),
+                                             eCommand_ID_About, nsMenuBarX::sNativeEventTarget);
+    if (itemBeingAdded) {
+      [sApplicationMenu addItem:itemBeingAdded];
+      [itemBeingAdded release];
+      itemBeingAdded = nil;
+
+      addAboutSeparator = TRUE;
+    }
+
+    // Add separator if either the About item or software update item exists
+    if (addAboutSeparator)
+      [sApplicationMenu addItem:[NSMenuItem separatorItem]];
+
+    // Add the Preferences menu item
+    itemBeingAdded = CreateNativeAppMenuItem(inMenu, NS_LITERAL_STRING("menu_preferences"), @selector(menuItemHit:),
+                                             eCommand_ID_Prefs, nsMenuBarX::sNativeEventTarget);
+    if (itemBeingAdded) {
+      [sApplicationMenu addItem:itemBeingAdded];
+      [itemBeingAdded release];
+      itemBeingAdded = nil;
+
+      // Add separator after Preferences menu
+      [sApplicationMenu addItem:[NSMenuItem separatorItem]];
+    }
+
+    // Add Services menu item
+    itemBeingAdded = CreateNativeAppMenuItem(inMenu, NS_LITERAL_STRING("menu_mac_services"), nil,
+                                             0, nil);
+    if (itemBeingAdded) {
+      [sApplicationMenu addItem:itemBeingAdded];
+
+      // set this menu item up as the Mac OS X Services menu
+      NSMenu* servicesMenu = [[GeckoServicesNSMenu alloc] initWithTitle:@""];
+      [itemBeingAdded setSubmenu:servicesMenu];
+      [NSApp setServicesMenu:servicesMenu];
+
+      [itemBeingAdded release];
+      itemBeingAdded = nil;
+
+      // Add separator after Services menu
+      [sApplicationMenu addItem:[NSMenuItem separatorItem]];
+    }
+
+    BOOL addHideShowSeparator = FALSE;
+
+    // Add menu item to hide this application
+    itemBeingAdded = CreateNativeAppMenuItem(inMenu, NS_LITERAL_STRING("menu_mac_hide_app"), @selector(menuItemHit:),
+                                             eCommand_ID_HideApp, nsMenuBarX::sNativeEventTarget);
+    if (itemBeingAdded) {
+      [sApplicationMenu addItem:itemBeingAdded];
+      [itemBeingAdded release];
+      itemBeingAdded = nil;
+
+      addHideShowSeparator = TRUE;
+    }
+
+    // Add menu item to hide other applications
+    itemBeingAdded = CreateNativeAppMenuItem(inMenu, NS_LITERAL_STRING("menu_mac_hide_others"), @selector(menuItemHit:),
+                                             eCommand_ID_HideOthers, nsMenuBarX::sNativeEventTarget);
+    if (itemBeingAdded) {
+      [sApplicationMenu addItem:itemBeingAdded];
+      [itemBeingAdded release];
+      itemBeingAdded = nil;
+
+      addHideShowSeparator = TRUE;
+    }
+
+    // Add menu item to show all applications
+    itemBeingAdded = CreateNativeAppMenuItem(inMenu, NS_LITERAL_STRING("menu_mac_show_all"), @selector(menuItemHit:),
+                                             eCommand_ID_ShowAll, nsMenuBarX::sNativeEventTarget);
+    if (itemBeingAdded) {
+      [sApplicationMenu addItem:itemBeingAdded];
+      [itemBeingAdded release];
+      itemBeingAdded = nil;
+
+      addHideShowSeparator = TRUE;
+    }
+
+    // Add a separator after the hide/show menus if at least one exists
+    if (addHideShowSeparator)
+      [sApplicationMenu addItem:[NSMenuItem separatorItem]];
+
+    // Add quit menu item
+    itemBeingAdded = CreateNativeAppMenuItem(inMenu, NS_LITERAL_STRING("menu_FileQuitItem"), @selector(menuItemHit:),
+                                             eCommand_ID_Quit, nsMenuBarX::sNativeEventTarget);
+    if (itemBeingAdded) {
+      [sApplicationMenu addItem:itemBeingAdded];
+      [itemBeingAdded release];
+      itemBeingAdded = nil;
+    }
+    else {
+      // the current application does not have a DOM node for "Quit". Add one
+      // anyway, in English.
+      NSMenuItem* defaultQuitItem = [[[NSMenuItem alloc] initWithTitle:@"Quit" action:@selector(menuItemHit:)
+                                                         keyEquivalent:@"q"] autorelease];
+      [defaultQuitItem setTarget:nsMenuBarX::sNativeEventTarget];
+      [defaultQuitItem setTag:eCommand_ID_Quit];
+      [sApplicationMenu addItem:defaultQuitItem];
+    }
+  }
+
+  return (sApplicationMenu) ? NS_OK : NS_ERROR_FAILURE;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void nsMenuBarX::SetParent(nsIWidget* aParent)
+{
+  mParentWindow = aParent;
+}
+
+//
+// Objective-C class used to allow us to have keyboard commands
+// look like they are doing something but actually do nothing.
+// We allow mouse actions to work normally.
+//
+
+// Controls whether or not native menu items should invoke their commands.
+static BOOL gMenuItemsExecuteCommands = YES;
+
+@implementation GeckoNSMenu
+
+// Keyboard commands should not cause menu items to invoke their
+// commands when there is a key window because we'd rather send
+// the keyboard command to the window. We still have the menus
+// go through the mechanics so they'll give the proper visual
+// feedback.
+- (BOOL)performKeyEquivalent:(NSEvent *)theEvent
+{
+  // We've noticed that Mac OS X expects this check in subclasses before
+  // calling NSMenu's "performKeyEquivalent:".
+  //
+  // There is no case in which we'd need to do anything or return YES
+  // when we have no items so we can just do this check first.
+  if ([self numberOfItems] <= 0) {
+    return NO;
+  }
+
+  NSWindow *keyWindow = [NSApp keyWindow];
+
+  // If there is no key window then just behave normally. This
+  // probably means that this menu is associated with Gecko's
+  // hidden window.
+  if (!keyWindow) {
+    return [super performKeyEquivalent:theEvent];
+  }
+
+  NSResponder *firstResponder = [keyWindow firstResponder];
+
+  gMenuItemsExecuteCommands = NO;
+  [super performKeyEquivalent:theEvent];
+  gMenuItemsExecuteCommands = YES; // return to default
+
+  // Return YES if we invoked a command and there is now no key window or we changed
+  // the first responder. In this case we do not want to propagate the event because
+  // we don't want it handled again.
+  if (![NSApp keyWindow] || [[NSApp keyWindow] firstResponder] != firstResponder) {
+    return YES;
+  }
+
+  // Return NO so that we can handle the event via NSView's "keyDown:".
+  return NO;
+}
+
+@end
+
+//
+// Objective-C class used as action target for menu items
+//
+
+@implementation NativeMenuItemTarget
+
+// called when some menu item in this menu gets hit
+-(IBAction)menuItemHit:(id)sender
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!gMenuItemsExecuteCommands) {
+    return;
+  }
+
+  int tag = [sender tag];
+
+  nsMenuGroupOwnerX* menuGroupOwner = nullptr;
+  nsMenuBarX* menuBar = nullptr;
+  MenuItemInfo* info = [sender representedObject];
+
+  if (info) {
+    menuGroupOwner = [info menuGroupOwner];
+    if (!menuGroupOwner) {
+      return;
+    }
+    if (menuGroupOwner->MenuObjectType() == eMenuBarObjectType) {
+      menuBar = static_cast<nsMenuBarX*>(menuGroupOwner);
+    }
+  }
+
+  // Do special processing if this is for an app-global command.
+  if (tag == eCommand_ID_About) {
+    nsIContent* mostSpecificContent = sAboutItemContent;
+    if (menuBar && menuBar->mAboutItemContent)
+      mostSpecificContent = menuBar->mAboutItemContent;
+    nsMenuUtilsX::DispatchCommandTo(mostSpecificContent);
+    return;
+  }
+  else if (tag == eCommand_ID_Prefs) {
+    nsIContent* mostSpecificContent = sPrefItemContent;
+    if (menuBar && menuBar->mPrefItemContent)
+      mostSpecificContent = menuBar->mPrefItemContent;
+    nsMenuUtilsX::DispatchCommandTo(mostSpecificContent);
+    return;
+  }
+  else if (tag == eCommand_ID_HideApp) {
+    [NSApp hide:sender];
+    return;
+  }
+  else if (tag == eCommand_ID_HideOthers) {
+    [NSApp hideOtherApplications:sender];
+    return;
+  }
+  else if (tag == eCommand_ID_ShowAll) {
+    [NSApp unhideAllApplications:sender];
+    return;
+  }
+  else if (tag == eCommand_ID_Quit) {
+    nsIContent* mostSpecificContent = sQuitItemContent;
+    if (menuBar && menuBar->mQuitItemContent)
+      mostSpecificContent = menuBar->mQuitItemContent;
+    // If we have some content for quit we execute it. Otherwise we send a native app terminate
+    // message. If you want to stop a quit from happening, provide quit content and return
+    // the event as unhandled.
+    if (mostSpecificContent) {
+      nsMenuUtilsX::DispatchCommandTo(mostSpecificContent);
+    }
+    else {
+      nsCOMPtr<nsIAppStartup> appStartup = do_GetService(NS_APPSTARTUP_CONTRACTID);
+      if (appStartup) {
+        appStartup->Quit(nsIAppStartup::eAttemptQuit);
+      }
+    }
+    return;
+  }
+
+  // given the commandID, look it up in our hashtable and dispatch to
+  // that menu item.
+  if (menuGroupOwner) {
+    nsMenuItemX* menuItem = menuGroupOwner->GetMenuItemForCommandID(static_cast<uint32_t>(tag));
+    if (menuItem)
+      menuItem->DoCommand();
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@end
+
+// Objective-C class used for menu items on the Services menu to allow Gecko
+// to override their standard behavior in order to stop key equivalents from
+// firing in certain instances. When gMenuItemsExecuteCommands is NO, we return
+// a dummy target and action instead of the actual target and action.
+
+@implementation GeckoServicesNSMenuItem
+
+- (id) target
+{
+  id realTarget = [super target];
+  if (gMenuItemsExecuteCommands)
+    return realTarget;
+  else
+    return realTarget ? self : nil;
+}
+
+- (SEL) action
+{
+  SEL realAction = [super action];
+  if (gMenuItemsExecuteCommands)
+    return realAction;
+  else
+    return realAction ? @selector(_doNothing:) : NULL;
+}
+
+- (void) _doNothing:(id)sender
+{
+}
+
+@end
+
+// Objective-C class used as the Services menu so that Gecko can override the
+// standard behavior of the Services menu in order to stop key equivalents
+// from firing in certain instances.
+
+@implementation GeckoServicesNSMenu
+
+- (void)addItem:(NSMenuItem *)newItem
+{
+  [self _overrideClassOfMenuItem:newItem];
+  [super addItem:newItem];
+}
+
+- (NSMenuItem *)addItemWithTitle:(NSString *)aString action:(SEL)aSelector keyEquivalent:(NSString *)keyEquiv
+{
+  NSMenuItem * newItem = [super addItemWithTitle:aString action:aSelector keyEquivalent:keyEquiv];
+  [self _overrideClassOfMenuItem:newItem];
+  return newItem;
+}
+
+- (void)insertItem:(NSMenuItem *)newItem atIndex:(NSInteger)index
+{
+  [self _overrideClassOfMenuItem:newItem];
+  [super insertItem:newItem atIndex:index];
+}
+
+- (NSMenuItem *)insertItemWithTitle:(NSString *)aString action:(SEL)aSelector  keyEquivalent:(NSString *)keyEquiv atIndex:(NSInteger)index
+{
+  NSMenuItem * newItem = [super insertItemWithTitle:aString action:aSelector keyEquivalent:keyEquiv atIndex:index];
+  [self _overrideClassOfMenuItem:newItem];
+  return newItem;
+}
+
+- (void) _overrideClassOfMenuItem:(NSMenuItem *)menuItem
+{
+  if ([menuItem class] == [NSMenuItem class])
+    object_setClass(menuItem, [GeckoServicesNSMenuItem class]);
+}
+
+@end
diff --git a/widget/cocoa/nsMenuBaseX.h b/widget/cocoa/nsMenuBaseX.h
new file mode 100644
index 0000000000..5b9f89c560
--- /dev/null
+++ b/widget/cocoa/nsMenuBaseX.h
@@ -0,0 +1,79 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsMenuBaseX_h_
+#define nsMenuBaseX_h_
+
+#import <Foundation/Foundation.h>
+
+#include "nsCOMPtr.h"
+#include "nsIContent.h"
+
+enum nsMenuObjectTypeX {
+  eMenuBarObjectType,
+  eSubmenuObjectType,
+  eMenuItemObjectType,
+  eStandaloneNativeMenuObjectType,
+};
+
+// All menu objects subclass this.
+// Menu bars are owned by their top-level nsIWidgets.
+// All other objects are memory-managed based on the DOM.
+// Content removal deletes them immediately and nothing else should.
+// Do not attempt to hold strong references to them or delete them.
+class nsMenuObjectX
+{
+public:
+  virtual ~nsMenuObjectX() { }
+  virtual nsMenuObjectTypeX MenuObjectType()=0;
+  virtual void*             NativeData()=0;
+  nsIContent*               Content() { return mContent; }
+
+  /**
+   * Called when an icon of a menu item somewhere in this menu has updated.
+   * Menu objects with parents need to propagate the notification to their
+   * parent.
+   */
+  virtual void IconUpdated() {}
+
+protected:
+  nsCOMPtr<nsIContent> mContent;
+};
+
+
+//
+// Object stored as "representedObject" for all menu items
+//
+
+class nsMenuGroupOwnerX;
+
+@interface MenuItemInfo : NSObject
+{
+  nsMenuGroupOwnerX * mMenuGroupOwner;
+}
+
+- (id) initWithMenuGroupOwner:(nsMenuGroupOwnerX *)aMenuGroupOwner;
+- (nsMenuGroupOwnerX *) menuGroupOwner;
+- (void) setMenuGroupOwner:(nsMenuGroupOwnerX *)aMenuGroupOwner;
+
+@end
+
+
+// Special command IDs that we know Mac OS X does not use for anything else.
+// We use these in place of carbon's IDs for these commands in order to stop
+// Carbon from messing with our event handlers. See bug 346883.
+
+enum {
+  eCommand_ID_About      = 1,
+  eCommand_ID_Prefs      = 2,
+  eCommand_ID_Quit       = 3,
+  eCommand_ID_HideApp    = 4,
+  eCommand_ID_HideOthers = 5,
+  eCommand_ID_ShowAll    = 6,
+  eCommand_ID_Update     = 7,
+  eCommand_ID_Last       = 8
+};
+
+#endif // nsMenuBaseX_h_
diff --git a/widget/cocoa/nsMenuGroupOwnerX.h b/widget/cocoa/nsMenuGroupOwnerX.h
new file mode 100644
index 0000000000..657f420b56
--- /dev/null
+++ b/widget/cocoa/nsMenuGroupOwnerX.h
@@ -0,0 +1,61 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsMenuGroupOwnerX_h_
+#define nsMenuGroupOwnerX_h_
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsMenuBaseX.h"
+#include "nsIMutationObserver.h"
+#include "nsHashKeys.h"
+#include "nsDataHashtable.h"
+#include "nsString.h"
+
+class nsMenuItemX;
+class nsChangeObserver;
+class nsIWidget;
+class nsIContent;
+
+class nsMenuGroupOwnerX : public nsMenuObjectX, public nsIMutationObserver
+{
+public:
+  nsMenuGroupOwnerX();
+
+  nsresult Create(nsIContent * aContent);
+
+  void RegisterForContentChanges(nsIContent* aContent,
+                                 nsChangeObserver* aMenuObject);
+  void UnregisterForContentChanges(nsIContent* aContent);
+  uint32_t RegisterForCommand(nsMenuItemX* aItem);
+  void UnregisterCommand(uint32_t aCommandID);
+  nsMenuItemX* GetMenuItemForCommandID(uint32_t inCommandID);
+  void AddMenuItemInfoToSet(MenuItemInfo* info);
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIMUTATIONOBSERVER
+
+protected:
+  virtual ~nsMenuGroupOwnerX();
+
+  nsChangeObserver* LookupContentChangeObserver(nsIContent* aContent);
+
+  uint32_t  mCurrentCommandID;  // unique command id (per menu-bar) to
+                                // give to next item that asks
+
+  // stores observers for content change notification
+  nsDataHashtable<nsPtrHashKey<nsIContent>, nsChangeObserver *> mContentToObserverTable;
+
+  // stores mapping of command IDs to menu objects
+  nsDataHashtable<nsUint32HashKey, nsMenuItemX *> mCommandToMenuObjectTable;
+
+  // Stores references to all the MenuItemInfo objects created with weak
+  // references to us.  They may live longer than we do, so when we're
+  // destroyed we need to clear all their weak references.  This avoids
+  // crashes in -[NativeMenuItemTarget menuItemHit:].  See bug 1131473.
+  NSMutableSet* mInfoSet;
+};
+
+#endif // nsMenuGroupOwner_h_
diff --git a/widget/cocoa/nsMenuGroupOwnerX.mm b/widget/cocoa/nsMenuGroupOwnerX.mm
new file mode 100644
index 0000000000..661a52bd80
--- /dev/null
+++ b/widget/cocoa/nsMenuGroupOwnerX.mm
@@ -0,0 +1,261 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsMenuGroupOwnerX.h"
+#include "nsMenuBarX.h"
+#include "nsMenuX.h"
+#include "nsMenuItemX.h"
+#include "nsMenuUtilsX.h"
+#include "nsCocoaUtils.h"
+#include "nsCocoaWindow.h"
+
+#include "nsCOMPtr.h"
+#include "nsString.h"
+#include "nsObjCExceptions.h"
+#include "nsThreadUtils.h"
+
+#include "mozilla/dom/Element.h"
+#include "nsIWidget.h"
+#include "nsIDocument.h"
+#include "nsIDOMDocument.h"
+#include "nsIDOMElement.h"
+
+#include "nsINode.h"
+
+using namespace mozilla;
+
+NS_IMPL_ISUPPORTS(nsMenuGroupOwnerX, nsIMutationObserver)
+
+
+nsMenuGroupOwnerX::nsMenuGroupOwnerX()
+: mCurrentCommandID(eCommand_ID_Last)
+{
+  mInfoSet = [[NSMutableSet setWithCapacity:10] retain];
+}
+
+
+nsMenuGroupOwnerX::~nsMenuGroupOwnerX()
+{
+  MOZ_ASSERT(mContentToObserverTable.Count() == 0, "have outstanding mutation observers!\n");
+
+  // The MenuItemInfo objects in mInfoSet may live longer than we do.  So when
+  // we get destroyed we need to invalidate all their mMenuGroupOwner pointers.
+  NSEnumerator* counter = [mInfoSet objectEnumerator];
+  MenuItemInfo* info;
+  while ((info = (MenuItemInfo*) [counter nextObject])) {
+    [info setMenuGroupOwner:nil];
+  }
+  [mInfoSet release];
+}
+
+
+nsresult nsMenuGroupOwnerX::Create(nsIContent* aContent)
+{
+  if (!aContent)
+    return NS_ERROR_INVALID_ARG;
+
+  mContent = aContent;
+
+  return NS_OK;
+}
+
+
+//
+// nsIMutationObserver
+//
+
+
+void nsMenuGroupOwnerX::CharacterDataWillChange(nsIDocument* aDocument,
+                                                nsIContent* aContent,
+                                                CharacterDataChangeInfo* aInfo)
+{
+}
+
+
+void nsMenuGroupOwnerX::CharacterDataChanged(nsIDocument* aDocument,
+                                             nsIContent* aContent,
+                                             CharacterDataChangeInfo* aInfo)
+{
+}
+
+
+void nsMenuGroupOwnerX::ContentAppended(nsIDocument* aDocument,
+                                        nsIContent* aContainer,
+                                        nsIContent* aFirstNewContent,
+                                        int32_t /* unused */)
+{
+  for (nsIContent* cur = aFirstNewContent; cur; cur = cur->GetNextSibling()) {
+    ContentInserted(aDocument, aContainer, cur, 0);
+  }
+}
+
+
+void nsMenuGroupOwnerX::NodeWillBeDestroyed(const nsINode * aNode)
+{
+}
+
+
+void nsMenuGroupOwnerX::AttributeWillChange(nsIDocument* aDocument,
+                                            dom::Element* aContent,
+                                            int32_t aNameSpaceID,
+                                            nsIAtom* aAttribute,
+                                            int32_t aModType,
+                                            const nsAttrValue* aNewValue)
+{
+}
+
+void nsMenuGroupOwnerX::NativeAnonymousChildListChange(nsIDocument* aDocument,
+                                                       nsIContent* aContent,
+                                                       bool aIsRemove)
+{
+}
+
+void nsMenuGroupOwnerX::AttributeChanged(nsIDocument* aDocument,
+                                         dom::Element* aElement,
+                                         int32_t aNameSpaceID,
+                                         nsIAtom* aAttribute,
+                                         int32_t aModType,
+                                         const nsAttrValue* aOldValue)
+{
+  nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+  nsChangeObserver* obs = LookupContentChangeObserver(aElement);
+  if (obs)
+    obs->ObserveAttributeChanged(aDocument, aElement, aAttribute);
+}
+
+
+void nsMenuGroupOwnerX::ContentRemoved(nsIDocument * aDocument,
+                                       nsIContent * aContainer,
+                                       nsIContent * aChild,
+                                       int32_t aIndexInContainer,
+                                       nsIContent * aPreviousSibling)
+{
+  if (!aContainer) {
+    return;
+  }
+
+  nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+  nsChangeObserver* obs = LookupContentChangeObserver(aContainer);
+  if (obs)
+    obs->ObserveContentRemoved(aDocument, aChild, aIndexInContainer);
+  else if (aContainer != mContent) {
+    // We do a lookup on the parent container in case things were removed
+    // under a "menupopup" item. That is basically a wrapper for the contents
+    // of a "menu" node.
+    nsCOMPtr<nsIContent> parent = aContainer->GetParent();
+    if (parent) {
+      obs = LookupContentChangeObserver(parent);
+      if (obs)
+        obs->ObserveContentRemoved(aDocument, aChild, aIndexInContainer);
+    }
+  }
+}
+
+
+void nsMenuGroupOwnerX::ContentInserted(nsIDocument * aDocument,
+                                        nsIContent * aContainer,
+                                        nsIContent * aChild,
+                                        int32_t /* unused */)
+{
+  if (!aContainer) {
+    return;
+  }
+
+  nsCOMPtr<nsIMutationObserver> kungFuDeathGrip(this);
+  nsChangeObserver* obs = LookupContentChangeObserver(aContainer);
+  if (obs)
+    obs->ObserveContentInserted(aDocument, aContainer, aChild);
+  else if (aContainer != mContent) {
+    // We do a lookup on the parent container in case things were removed
+    // under a "menupopup" item. That is basically a wrapper for the contents
+    // of a "menu" node.
+    nsCOMPtr<nsIContent> parent = aContainer->GetParent();
+    if (parent) {
+      obs = LookupContentChangeObserver(parent);
+      if (obs)
+        obs->ObserveContentInserted(aDocument, aContainer, aChild);
+    }
+  }
+}
+
+
+void nsMenuGroupOwnerX::ParentChainChanged(nsIContent *aContent)
+{
+}
+
+
+// For change management, we don't use a |nsSupportsHashtable| because
+// we know that the lifetime of all these items is bounded by the
+// lifetime of the menubar. No need to add any more strong refs to the
+// picture because the containment hierarchy already uses strong refs.
+void nsMenuGroupOwnerX::RegisterForContentChanges(nsIContent *aContent,
+                                                  nsChangeObserver *aMenuObject)
+{
+  if (!mContentToObserverTable.Contains(aContent)) {
+    aContent->AddMutationObserver(this);
+  }
+  mContentToObserverTable.Put(aContent, aMenuObject);
+}
+
+
+void nsMenuGroupOwnerX::UnregisterForContentChanges(nsIContent *aContent)
+{
+  if (mContentToObserverTable.Contains(aContent)) {
+    aContent->RemoveMutationObserver(this);
+  }
+  mContentToObserverTable.Remove(aContent);
+}
+
+
+nsChangeObserver* nsMenuGroupOwnerX::LookupContentChangeObserver(nsIContent* aContent)
+{
+  nsChangeObserver * result;
+  if (mContentToObserverTable.Get(aContent, &result))
+    return result;
+  else
+    return nullptr;
+}
+
+
+// Given a menu item, creates a unique 4-character command ID and
+// maps it to the item. Returns the id for use by the client.
+uint32_t nsMenuGroupOwnerX::RegisterForCommand(nsMenuItemX* inMenuItem)
+{
+  // no real need to check for uniqueness. We always start afresh with each
+  // window at 1. Even if we did get close to the reserved Apple command id's,
+  // those don't start until at least '    ', which is integer 538976288. If
+  // we have that many menu items in one window, I think we have other
+  // problems.
+
+  // make id unique
+  ++mCurrentCommandID;
+
+  mCommandToMenuObjectTable.Put(mCurrentCommandID, inMenuItem);
+
+  return mCurrentCommandID;
+}
+
+
+// Removes the mapping between the given 4-character command ID
+// and its associated menu item.
+void nsMenuGroupOwnerX::UnregisterCommand(uint32_t inCommandID)
+{
+  mCommandToMenuObjectTable.Remove(inCommandID);
+}
+
+
+nsMenuItemX* nsMenuGroupOwnerX::GetMenuItemForCommandID(uint32_t inCommandID)
+{
+  nsMenuItemX * result;
+  if (mCommandToMenuObjectTable.Get(inCommandID, &result))
+    return result;
+  else
+    return nullptr;
+}
+
+void nsMenuGroupOwnerX::AddMenuItemInfoToSet(MenuItemInfo* info)
+{
+  [mInfoSet addObject:info];
+}
diff --git a/widget/cocoa/nsMenuItemIconX.h b/widget/cocoa/nsMenuItemIconX.h
new file mode 100644
index 0000000000..7352a94e2a
--- /dev/null
+++ b/widget/cocoa/nsMenuItemIconX.h
@@ -0,0 +1,66 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Retrieves and displays icons in native menu items on Mac OS X.
+ */
+
+#ifndef nsMenuItemIconX_h_
+#define nsMenuItemIconX_h_
+
+#include "mozilla/RefPtr.h"
+#include "nsCOMPtr.h"
+#include "imgINotificationObserver.h"
+
+class nsIURI;
+class nsIContent;
+class imgRequestProxy;
+class nsMenuObjectX;
+
+#import <Cocoa/Cocoa.h>
+
+class nsMenuItemIconX : public imgINotificationObserver
+{
+public:
+  nsMenuItemIconX(nsMenuObjectX* aMenuItem,
+                  nsIContent*    aContent,
+                  NSMenuItem*    aNativeMenuItem);
+private:
+  virtual ~nsMenuItemIconX();
+
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_IMGINOTIFICATIONOBSERVER
+
+  // SetupIcon succeeds if it was able to set up the icon, or if there should
+  // be no icon, in which case it clears any existing icon but still succeeds.
+  nsresult SetupIcon();
+
+  // GetIconURI fails if the item should not have any icon.
+  nsresult GetIconURI(nsIURI** aIconURI);
+
+  // LoadIcon will set a placeholder image and start a load request for the
+  // icon.  The request may not complete until after LoadIcon returns.
+  nsresult LoadIcon(nsIURI* aIconURI);
+
+  // Unless we take precautions, we may outlive the object that created us
+  // (mMenuObject, which owns our native menu item (mNativeMenuItem)).
+  // Destroy() should be called from mMenuObject's destructor to prevent
+  // this from happening.  See bug 499600.
+  void Destroy();
+
+protected:
+  nsresult OnFrameComplete(imgIRequest* aRequest);
+
+  nsCOMPtr<nsIContent>      mContent;
+  RefPtr<imgRequestProxy> mIconRequest;
+  nsMenuObjectX*            mMenuObject; // [weak]
+  nsIntRect                 mImageRegionRect;
+  bool                      mLoadedIcon;
+  bool                      mSetIcon;
+  NSMenuItem*               mNativeMenuItem; // [weak]
+};
+
+#endif // nsMenuItemIconX_h_
diff --git a/widget/cocoa/nsMenuItemIconX.mm b/widget/cocoa/nsMenuItemIconX.mm
new file mode 100644
index 0000000000..7589c279e5
--- /dev/null
+++ b/widget/cocoa/nsMenuItemIconX.mm
@@ -0,0 +1,466 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Retrieves and displays icons in native menu items on Mac OS X.
+ */
+
+/* exception_defines.h defines 'try' to 'if (true)' which breaks objective-c
+   exceptions and produces errors like: error: unexpected '@' in program'.
+   If we define __EXCEPTIONS exception_defines.h will avoid doing this.
+
+   See bug 666609 for more information.
+
+   We use <limits> to get the libstdc++ version. */
+#include <limits>
+#if __GLIBCXX__ <= 20070719
+#ifndef __EXCEPTIONS
+#define __EXCEPTIONS
+#endif
+#endif
+
+#include "nsMenuItemIconX.h"
+#include "nsObjCExceptions.h"
+#include "nsIContent.h"
+#include "nsIDocument.h"
+#include "nsNameSpaceManager.h"
+#include "nsGkAtoms.h"
+#include "nsIDOMElement.h"
+#include "nsICSSDeclaration.h"
+#include "nsIDOMCSSValue.h"
+#include "nsIDOMCSSPrimitiveValue.h"
+#include "nsIDOMRect.h"
+#include "nsThreadUtils.h"
+#include "nsToolkit.h"
+#include "nsNetUtil.h"
+#include "imgLoader.h"
+#include "imgRequestProxy.h"
+#include "nsMenuItemX.h"
+#include "gfxPlatform.h"
+#include "imgIContainer.h"
+#include "nsCocoaUtils.h"
+#include "nsContentUtils.h"
+#include "nsIContentPolicy.h"
+
+using mozilla::dom::Element;
+using mozilla::gfx::SourceSurface;
+
+static const uint32_t kIconWidth = 16;
+static const uint32_t kIconHeight = 16;
+
+typedef NS_STDCALL_FUNCPROTO(nsresult, GetRectSideMethod, nsIDOMRect,
+                             GetBottom, (nsIDOMCSSPrimitiveValue**));
+
+NS_IMPL_ISUPPORTS(nsMenuItemIconX, imgINotificationObserver)
+
+nsMenuItemIconX::nsMenuItemIconX(nsMenuObjectX* aMenuItem,
+                                 nsIContent*    aContent,
+                                 NSMenuItem*    aNativeMenuItem)
+: mContent(aContent)
+, mMenuObject(aMenuItem)
+, mLoadedIcon(false)
+, mSetIcon(false)
+, mNativeMenuItem(aNativeMenuItem)
+{
+  //  printf("Creating icon for menu item %d, menu %d, native item is %d\n", aMenuItem, aMenu, aNativeMenuItem);
+}
+
+nsMenuItemIconX::~nsMenuItemIconX()
+{
+  if (mIconRequest)
+    mIconRequest->CancelAndForgetObserver(NS_BINDING_ABORTED);
+}
+
+// Called from mMenuObjectX's destructor, to prevent us from outliving it
+// (as might otherwise happen if calls to our imgINotificationObserver methods
+// are still outstanding).  mMenuObjectX owns our nNativeMenuItem.
+void nsMenuItemIconX::Destroy()
+{
+  if (mIconRequest) {
+    mIconRequest->CancelAndForgetObserver(NS_BINDING_ABORTED);
+    mIconRequest = nullptr;
+  }
+  mMenuObject = nullptr;
+  mNativeMenuItem = nil;
+}
+
+nsresult
+nsMenuItemIconX::SetupIcon()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  // Still don't have one, then something is wrong, get out of here.
+  if (!mNativeMenuItem) {
+    NS_ERROR("No native menu item");
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIURI> iconURI;
+  nsresult rv = GetIconURI(getter_AddRefs(iconURI));
+  if (NS_FAILED(rv)) {
+    // There is no icon for this menu item. An icon might have been set
+    // earlier.  Clear it.
+    [mNativeMenuItem setImage:nil];
+
+    return NS_OK;
+  }
+
+  rv = LoadIcon(iconURI);
+  if (NS_FAILED(rv)) {
+    // There is no icon for this menu item, as an error occurred while loading it.
+    // An icon might have been set earlier or the place holder icon may have
+    // been set.  Clear it.
+    [mNativeMenuItem setImage:nil];
+  }
+  return rv;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+static int32_t
+GetDOMRectSide(nsIDOMRect* aRect, GetRectSideMethod aMethod)
+{
+  nsCOMPtr<nsIDOMCSSPrimitiveValue> dimensionValue;
+  (aRect->*aMethod)(getter_AddRefs(dimensionValue));
+  if (!dimensionValue)
+    return -1;
+
+  uint16_t primitiveType;
+  nsresult rv = dimensionValue->GetPrimitiveType(&primitiveType);
+  if (NS_FAILED(rv) || primitiveType != nsIDOMCSSPrimitiveValue::CSS_PX)
+    return -1;
+
+  float dimension = 0;
+  rv = dimensionValue->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_PX,
+                                     &dimension);
+  if (NS_FAILED(rv))
+    return -1;
+
+  return NSToIntRound(dimension);
+}
+
+nsresult
+nsMenuItemIconX::GetIconURI(nsIURI** aIconURI)
+{
+  if (!mMenuObject)
+    return NS_ERROR_FAILURE;
+
+  // Mac native menu items support having both a checkmark and an icon
+  // simultaneously, but this is unheard of in the cross-platform toolkit,
+  // seemingly because the win32 theme is unable to cope with both at once.
+  // The downside is that it's possible to get a menu item marked with a
+  // native checkmark and a checkmark for an icon.  Head off that possibility
+  // by pretending that no icon exists if this is a checkable menu item.
+  if (mMenuObject->MenuObjectType() == eMenuItemObjectType) {
+    nsMenuItemX* menuItem = static_cast<nsMenuItemX*>(mMenuObject);
+    if (menuItem->GetMenuItemType() != eRegularMenuItemType)
+      return NS_ERROR_FAILURE;
+  }
+
+  if (!mContent)
+    return NS_ERROR_FAILURE;
+
+  // First, look at the content node's "image" attribute.
+  nsAutoString imageURIString;
+  bool hasImageAttr = mContent->GetAttr(kNameSpaceID_None,
+                                        nsGkAtoms::image,
+                                        imageURIString);
+
+  nsresult rv;
+  nsCOMPtr<nsIDOMCSSValue> cssValue;
+  nsCOMPtr<nsICSSDeclaration> cssStyleDecl;
+  nsCOMPtr<nsIDOMCSSPrimitiveValue> primitiveValue;
+  uint16_t primitiveType;
+  if (!hasImageAttr) {
+    // If the content node has no "image" attribute, get the
+    // "list-style-image" property from CSS.
+    nsCOMPtr<nsIDocument> document = mContent->GetComposedDoc();
+    if (!document)
+      return NS_ERROR_FAILURE;
+
+    nsCOMPtr<nsPIDOMWindowInner> window = document->GetInnerWindow();
+    if (!window)
+      return NS_ERROR_FAILURE;
+
+    nsCOMPtr<Element> domElement = do_QueryInterface(mContent);
+    if (!domElement)
+      return NS_ERROR_FAILURE;
+
+    ErrorResult dummy;
+    cssStyleDecl = window->GetComputedStyle(*domElement, EmptyString(), dummy);
+    dummy.SuppressException();
+    if (!cssStyleDecl)
+      return NS_ERROR_FAILURE;
+
+    NS_NAMED_LITERAL_STRING(listStyleImage, "list-style-image");
+    rv = cssStyleDecl->GetPropertyCSSValue(listStyleImage,
+                                           getter_AddRefs(cssValue));
+    if (NS_FAILED(rv)) return rv;
+
+    primitiveValue = do_QueryInterface(cssValue);
+    if (!primitiveValue) return NS_ERROR_FAILURE;
+
+    rv = primitiveValue->GetPrimitiveType(&primitiveType);
+    if (NS_FAILED(rv)) return rv;
+    if (primitiveType != nsIDOMCSSPrimitiveValue::CSS_URI)
+      return NS_ERROR_FAILURE;
+
+    rv = primitiveValue->GetStringValue(imageURIString);
+    if (NS_FAILED(rv)) return rv;
+  }
+
+  // Empty the mImageRegionRect initially as the image region CSS could
+  // have been changed and now have an error or have been removed since the
+  // last GetIconURI call.
+  mImageRegionRect.SetEmpty();
+
+  // If this menu item shouldn't have an icon, the string will be empty,
+  // and NS_NewURI will fail.
+  nsCOMPtr<nsIURI> iconURI;
+  rv = NS_NewURI(getter_AddRefs(iconURI), imageURIString);
+  if (NS_FAILED(rv)) return rv;
+
+  *aIconURI = iconURI;
+  NS_ADDREF(*aIconURI);
+
+  if (!hasImageAttr) {
+    // Check if the icon has a specified image region so that it can be
+    // cropped appropriately before being displayed.
+    NS_NAMED_LITERAL_STRING(imageRegion, "-moz-image-region");
+    rv = cssStyleDecl->GetPropertyCSSValue(imageRegion,
+                                           getter_AddRefs(cssValue));
+    // Just return NS_OK if there if there is a failure due to no
+    // moz-image region specified so the whole icon will be drawn anyway.
+    if (NS_FAILED(rv)) return NS_OK;
+
+    primitiveValue = do_QueryInterface(cssValue);
+    if (!primitiveValue) return NS_OK;
+
+    rv = primitiveValue->GetPrimitiveType(&primitiveType);
+    if (NS_FAILED(rv)) return NS_OK;
+    if (primitiveType != nsIDOMCSSPrimitiveValue::CSS_RECT)
+      return NS_OK;
+
+    nsCOMPtr<nsIDOMRect> imageRegionRect;
+    rv = primitiveValue->GetRectValue(getter_AddRefs(imageRegionRect));
+    if (NS_FAILED(rv)) return NS_OK;
+
+    if (imageRegionRect) {
+      // Return NS_ERROR_FAILURE if the image region is invalid so the image
+      // is not drawn, and behavior is similar to XUL menus.
+      int32_t bottom = GetDOMRectSide(imageRegionRect, &nsIDOMRect::GetBottom);
+      int32_t right = GetDOMRectSide(imageRegionRect, &nsIDOMRect::GetRight);
+      int32_t top = GetDOMRectSide(imageRegionRect, &nsIDOMRect::GetTop);
+      int32_t left = GetDOMRectSide(imageRegionRect, &nsIDOMRect::GetLeft);
+
+      if (top < 0 || left < 0 || bottom <= top || right <= left)
+        return NS_ERROR_FAILURE;
+
+      mImageRegionRect.SetRect(left, top, right - left, bottom - top);
+    }
+  }
+
+  return NS_OK;
+}
+
+nsresult
+nsMenuItemIconX::LoadIcon(nsIURI* aIconURI)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (mIconRequest) {
+    // Another icon request is already in flight.  Kill it.
+    mIconRequest->Cancel(NS_BINDING_ABORTED);
+    mIconRequest = nullptr;
+  }
+
+  mLoadedIcon = false;
+
+  if (!mContent) return NS_ERROR_FAILURE;
+
+  nsCOMPtr<nsIDocument> document = mContent->OwnerDoc();
+
+  nsCOMPtr<nsILoadGroup> loadGroup = document->GetDocumentLoadGroup();
+  if (!loadGroup) return NS_ERROR_FAILURE;
+
+  RefPtr<imgLoader> loader = nsContentUtils::GetImgLoaderForDocument(document);
+  if (!loader) return NS_ERROR_FAILURE;
+
+  if (!mSetIcon) {
+    // Set a completely transparent 16x16 image as the icon on this menu item
+    // as a placeholder.  This keeps the menu item text displayed in the same
+    // position that it will be displayed when the real icon is loaded, and
+    // prevents it from jumping around or looking misaligned.
+
+    static bool sInitializedPlaceholder;
+    static NSImage* sPlaceholderIconImage;
+    if (!sInitializedPlaceholder) {
+      sInitializedPlaceholder = true;
+
+      // Note that we only create the one and reuse it forever, so this is not a leak.
+      sPlaceholderIconImage = [[NSImage alloc] initWithSize:NSMakeSize(kIconWidth, kIconHeight)];
+    }
+
+    if (!sPlaceholderIconImage) return NS_ERROR_FAILURE;
+
+    if (mNativeMenuItem)
+      [mNativeMenuItem setImage:sPlaceholderIconImage];
+  }
+
+  nsresult rv = loader->LoadImage(aIconURI, nullptr, nullptr,
+                                  mozilla::net::RP_Default,
+                                  nullptr, loadGroup, this,
+                                  nullptr, nullptr, nsIRequest::LOAD_NORMAL, nullptr,
+                                  nsIContentPolicy::TYPE_INTERNAL_IMAGE, EmptyString(),
+                                  getter_AddRefs(mIconRequest));
+  if (NS_FAILED(rv)) return rv;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+//
+// imgINotificationObserver
+//
+
+NS_IMETHODIMP
+nsMenuItemIconX::Notify(imgIRequest* aRequest,
+                        int32_t aType,
+                        const nsIntRect* aData)
+{
+  if (aType == imgINotificationObserver::LOAD_COMPLETE) {
+    // Make sure the image loaded successfully.
+    uint32_t status = imgIRequest::STATUS_ERROR;
+    if (NS_FAILED(aRequest->GetImageStatus(&status)) ||
+        (status & imgIRequest::STATUS_ERROR)) {
+      mIconRequest->Cancel(NS_BINDING_ABORTED);
+      mIconRequest = nullptr;
+      return NS_ERROR_FAILURE;
+    }
+
+    nsCOMPtr<imgIContainer> image;
+    aRequest->GetImage(getter_AddRefs(image));
+    MOZ_ASSERT(image);
+
+    // Ask the image to decode at its intrinsic size.
+    int32_t width = 0, height = 0;
+    image->GetWidth(&width);
+    image->GetHeight(&height);
+    image->RequestDecodeForSize(nsIntSize(width, height), imgIContainer::FLAG_NONE);
+  }
+
+  if (aType == imgINotificationObserver::FRAME_COMPLETE) {
+    return OnFrameComplete(aRequest);
+  }
+
+  if (aType == imgINotificationObserver::DECODE_COMPLETE) {
+    if (mIconRequest && mIconRequest == aRequest) {
+      mIconRequest->Cancel(NS_BINDING_ABORTED);
+      mIconRequest = nullptr;
+    }
+  }
+
+  return NS_OK;
+}
+
+nsresult
+nsMenuItemIconX::OnFrameComplete(imgIRequest* aRequest)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (aRequest != mIconRequest)
+    return NS_ERROR_FAILURE;
+
+  // Only support one frame.
+  if (mLoadedIcon)
+    return NS_OK;
+
+  if (!mNativeMenuItem)
+    return NS_ERROR_FAILURE;
+
+  nsCOMPtr<imgIContainer> imageContainer;
+  aRequest->GetImage(getter_AddRefs(imageContainer));
+  if (!imageContainer) {
+    [mNativeMenuItem setImage:nil];
+    return NS_ERROR_FAILURE;
+  }
+
+  int32_t origWidth = 0, origHeight = 0;
+  imageContainer->GetWidth(&origWidth);
+  imageContainer->GetHeight(&origHeight);
+
+  // If the image region is invalid, don't draw the image to almost match
+  // the behavior of other platforms.
+  if (!mImageRegionRect.IsEmpty() &&
+      (mImageRegionRect.XMost() > origWidth ||
+       mImageRegionRect.YMost() > origHeight)) {
+    [mNativeMenuItem setImage:nil];
+    return NS_ERROR_FAILURE;
+  }
+
+  if (mImageRegionRect.IsEmpty()) {
+    mImageRegionRect.SetRect(0, 0, origWidth, origHeight);
+  }
+
+  RefPtr<SourceSurface> surface =
+    imageContainer->GetFrame(imgIContainer::FRAME_CURRENT,
+                             imgIContainer::FLAG_SYNC_DECODE);
+  if (!surface) {
+    [mNativeMenuItem setImage:nil];
+    return NS_ERROR_FAILURE;
+  }
+
+  CGImageRef origImage = NULL;
+  nsresult rv = nsCocoaUtils::CreateCGImageFromSurface(surface, &origImage);
+  if (NS_FAILED(rv) || !origImage) {
+    [mNativeMenuItem setImage:nil];
+    return NS_ERROR_FAILURE;
+  }
+
+  bool createSubImage = !(mImageRegionRect.x == 0 && mImageRegionRect.y == 0 &&
+                            mImageRegionRect.width == origWidth && mImageRegionRect.height == origHeight);
+
+  CGImageRef finalImage = origImage;
+  if (createSubImage) {
+    // if mImageRegionRect is set using CSS, we need to slice a piece out of the overall
+    // image to use as the icon
+    finalImage = ::CGImageCreateWithImageInRect(origImage,
+                                                ::CGRectMake(mImageRegionRect.x,
+                                                mImageRegionRect.y,
+                                                mImageRegionRect.width,
+                                                mImageRegionRect.height));
+    ::CGImageRelease(origImage);
+    if (!finalImage) {
+      [mNativeMenuItem setImage:nil];
+      return NS_ERROR_FAILURE;
+    }
+  }
+
+  NSImage *newImage = nil;
+  rv = nsCocoaUtils::CreateNSImageFromCGImage(finalImage, &newImage);
+  if (NS_FAILED(rv) || !newImage) {
+    [mNativeMenuItem setImage:nil];
+    ::CGImageRelease(finalImage);
+    return NS_ERROR_FAILURE;
+  }
+
+  [newImage setSize:NSMakeSize(kIconWidth, kIconHeight)];
+  [mNativeMenuItem setImage:newImage];
+
+  [newImage release];
+  ::CGImageRelease(finalImage);
+
+  mLoadedIcon = true;
+  mSetIcon = true;
+
+  if (mMenuObject) {
+    mMenuObject->IconUpdated();
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
diff --git a/widget/cocoa/nsMenuItemX.h b/widget/cocoa/nsMenuItemX.h
new file mode 100644
index 0000000000..67ae32c99c
--- /dev/null
+++ b/widget/cocoa/nsMenuItemX.h
@@ -0,0 +1,75 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsMenuItemX_h_
+#define nsMenuItemX_h_
+
+#include "mozilla/RefPtr.h"
+#include "nsMenuBaseX.h"
+#include "nsMenuGroupOwnerX.h"
+#include "nsChangeObserver.h"
+
+#import <Cocoa/Cocoa.h>
+
+class nsString;
+class nsMenuItemIconX;
+class nsMenuX;
+
+enum {
+  knsMenuItemNoModifier      = 0,
+  knsMenuItemShiftModifier   = (1 << 0),
+  knsMenuItemAltModifier     = (1 << 1),
+  knsMenuItemControlModifier = (1 << 2),
+  knsMenuItemCommandModifier = (1 << 3)
+};
+
+enum EMenuItemType {
+  eRegularMenuItemType = 0,
+  eCheckboxMenuItemType,
+  eRadioMenuItemType,
+  eSeparatorMenuItemType
+};
+
+
+// Once instantiated, this object lives until its DOM node or its parent window is destroyed.
+// Do not hold references to this, they can become invalid any time the DOM node can be destroyed.
+class nsMenuItemX : public nsMenuObjectX,
+                    public nsChangeObserver
+{
+public:
+  nsMenuItemX();
+  virtual ~nsMenuItemX();
+
+  NS_DECL_CHANGEOBSERVER
+
+  // nsMenuObjectX
+  void*             NativeData() override {return (void*)mNativeMenuItem;}
+  nsMenuObjectTypeX MenuObjectType() override {return eMenuItemObjectType;}
+
+  // nsMenuItemX
+  nsresult      Create(nsMenuX* aParent, const nsString& aLabel, EMenuItemType aItemType,
+                       nsMenuGroupOwnerX* aMenuGroupOwner, nsIContent* aNode);
+  nsresult      SetChecked(bool aIsChecked);
+  EMenuItemType GetMenuItemType();
+  void          DoCommand();
+  nsresult      DispatchDOMEvent(const nsString &eventName, bool* preventDefaultCalled);
+  void          SetupIcon();
+
+protected:
+  void UncheckRadioSiblings(nsIContent* inCheckedElement);
+  void SetKeyEquiv();
+
+  EMenuItemType             mType;
+  // nsMenuItemX objects should always have a valid native menu item.
+  NSMenuItem*               mNativeMenuItem;      // [strong]
+  nsMenuX*                  mMenuParent;          // [weak]
+  nsMenuGroupOwnerX*        mMenuGroupOwner;      // [weak]
+  nsCOMPtr<nsIContent>      mCommandContent;
+  // The icon object should never outlive its creating nsMenuItemX object.
+  RefPtr<nsMenuItemIconX> mIcon;
+  bool                      mIsChecked;
+};
+
+#endif // nsMenuItemX_h_
diff --git a/widget/cocoa/nsMenuItemX.mm b/widget/cocoa/nsMenuItemX.mm
new file mode 100644
index 0000000000..114b69f430
--- /dev/null
+++ b/widget/cocoa/nsMenuItemX.mm
@@ -0,0 +1,369 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsMenuItemX.h"
+#include "nsMenuBarX.h"
+#include "nsMenuX.h"
+#include "nsMenuItemIconX.h"
+#include "nsMenuUtilsX.h"
+#include "nsCocoaUtils.h"
+
+#include "nsObjCExceptions.h"
+
+#include "nsCOMPtr.h"
+#include "nsGkAtoms.h"
+
+#include "mozilla/dom/Element.h"
+#include "nsIWidget.h"
+#include "nsIDocument.h"
+#include "nsIDOMDocument.h"
+#include "nsIDOMElement.h"
+#include "nsIDOMEvent.h"
+
+nsMenuItemX::nsMenuItemX()
+{
+  mType           = eRegularMenuItemType;
+  mNativeMenuItem = nil;
+  mMenuParent     = nullptr;
+  mMenuGroupOwner = nullptr;
+  mIsChecked      = false;
+
+  MOZ_COUNT_CTOR(nsMenuItemX);
+}
+
+nsMenuItemX::~nsMenuItemX()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Prevent the icon object from outliving us.
+  if (mIcon)
+    mIcon->Destroy();
+
+  // autorelease the native menu item so that anything else happening to this
+  // object happens before the native menu item actually dies
+  [mNativeMenuItem autorelease];
+
+  if (mContent)
+    mMenuGroupOwner->UnregisterForContentChanges(mContent);
+  if (mCommandContent)
+    mMenuGroupOwner->UnregisterForContentChanges(mCommandContent);
+
+  MOZ_COUNT_DTOR(nsMenuItemX);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsresult nsMenuItemX::Create(nsMenuX* aParent, const nsString& aLabel, EMenuItemType aItemType,
+                             nsMenuGroupOwnerX* aMenuGroupOwner, nsIContent* aNode)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  mType = aItemType;
+  mMenuParent = aParent;
+  mContent = aNode;
+
+  mMenuGroupOwner = aMenuGroupOwner;
+  NS_ASSERTION(mMenuGroupOwner, "No menu owner given, must have one!");
+
+  mMenuGroupOwner->RegisterForContentChanges(mContent, this);
+
+  nsIDocument *doc = mContent->GetUncomposedDoc();
+
+  // if we have a command associated with this menu item, register for changes
+  // to the command DOM node
+  if (doc) {
+    nsAutoString ourCommand;
+    mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::command, ourCommand);
+
+    if (!ourCommand.IsEmpty()) {
+      nsIContent *commandElement = doc->GetElementById(ourCommand);
+
+      if (commandElement) {
+        mCommandContent = commandElement;
+        // register to observe the command DOM element
+        mMenuGroupOwner->RegisterForContentChanges(mCommandContent, this);
+      }
+    }
+  }
+
+  // decide enabled state based on command content if it exists, otherwise do it based
+  // on our own content
+  bool isEnabled;
+  if (mCommandContent)
+    isEnabled = !mCommandContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled, nsGkAtoms::_true, eCaseMatters);
+  else
+    isEnabled = !mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled, nsGkAtoms::_true, eCaseMatters);
+
+  // set up the native menu item
+  if (mType == eSeparatorMenuItemType) {
+    mNativeMenuItem = [[NSMenuItem separatorItem] retain];
+  }
+  else {
+    NSString *newCocoaLabelString = nsMenuUtilsX::GetTruncatedCocoaLabel(aLabel);
+    mNativeMenuItem = [[NSMenuItem alloc] initWithTitle:newCocoaLabelString action:nil keyEquivalent:@""];
+
+    [mNativeMenuItem setEnabled:(BOOL)isEnabled];
+
+    SetChecked(mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::checked,
+                                     nsGkAtoms::_true, eCaseMatters));
+    SetKeyEquiv();
+  }
+
+  mIcon = new nsMenuItemIconX(this, mContent, mNativeMenuItem);
+  if (!mIcon)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult nsMenuItemX::SetChecked(bool aIsChecked)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  mIsChecked = aIsChecked;
+
+  // update the content model. This will also handle unchecking our siblings
+  // if we are a radiomenu
+  mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::checked,
+                    mIsChecked ? NS_LITERAL_STRING("true") : NS_LITERAL_STRING("false"), true);
+
+  // update native menu item
+  if (mIsChecked)
+    [mNativeMenuItem setState:NSOnState];
+  else
+    [mNativeMenuItem setState:NSOffState];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+EMenuItemType nsMenuItemX::GetMenuItemType()
+{
+  return mType;
+}
+
+// Executes the "cached" javaScript command.
+// Returns NS_OK if the command was executed properly, otherwise an error code.
+void nsMenuItemX::DoCommand()
+{
+  // flip "checked" state if we're a checkbox menu, or an un-checked radio menu
+  if (mType == eCheckboxMenuItemType ||
+      (mType == eRadioMenuItemType && !mIsChecked)) {
+    if (!mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::autocheck,
+                               nsGkAtoms::_false, eCaseMatters))
+    SetChecked(!mIsChecked);
+    /* the AttributeChanged code will update all the internal state */
+  }
+
+  nsMenuUtilsX::DispatchCommandTo(mContent);
+}
+
+nsresult nsMenuItemX::DispatchDOMEvent(const nsString &eventName, bool *preventDefaultCalled)
+{
+  if (!mContent)
+    return NS_ERROR_FAILURE;
+
+  // get owner document for content
+  nsCOMPtr<nsIDocument> parentDoc = mContent->OwnerDoc();
+
+  // get interface for creating DOM events from content owner document
+  nsCOMPtr<nsIDOMDocument> domDoc = do_QueryInterface(parentDoc);
+  if (!domDoc) {
+    NS_WARNING("Failed to QI parent nsIDocument to nsIDOMDocument");
+    return NS_ERROR_FAILURE;
+  }
+
+  // create DOM event
+  nsCOMPtr<nsIDOMEvent> event;
+  nsresult rv = domDoc->CreateEvent(NS_LITERAL_STRING("Events"), getter_AddRefs(event));
+  if (NS_FAILED(rv)) {
+    NS_WARNING("Failed to create nsIDOMEvent");
+    return rv;
+  }
+  event->InitEvent(eventName, true, true);
+
+  // mark DOM event as trusted
+  event->SetTrusted(true);
+
+  // send DOM event
+  rv = mContent->DispatchEvent(event, preventDefaultCalled);
+  if (NS_FAILED(rv)) {
+    NS_WARNING("Failed to send DOM event via EventTarget");
+    return rv;
+  }
+
+  return NS_OK;
+}
+
+// Walk the sibling list looking for nodes with the same name and
+// uncheck them all.
+void nsMenuItemX::UncheckRadioSiblings(nsIContent* inCheckedContent)
+{
+  nsAutoString myGroupName;
+  inCheckedContent->GetAttr(kNameSpaceID_None, nsGkAtoms::name, myGroupName);
+  if (!myGroupName.Length()) // no groupname, nothing to do
+    return;
+
+  nsCOMPtr<nsIContent> parent = inCheckedContent->GetParent();
+  if (!parent)
+    return;
+
+  // loop over siblings
+  uint32_t count = parent->GetChildCount();
+  for (uint32_t i = 0; i < count; i++) {
+    nsIContent *sibling = parent->GetChildAt(i);
+    if (sibling) {
+      if (sibling != inCheckedContent) { // skip this node
+        // if the current sibling is in the same group, clear it
+        if (sibling->AttrValueIs(kNameSpaceID_None, nsGkAtoms::name,
+                                 myGroupName, eCaseMatters))
+          sibling->SetAttr(kNameSpaceID_None, nsGkAtoms::checked, NS_LITERAL_STRING("false"), true);
+      }
+    }
+  }
+}
+
+void nsMenuItemX::SetKeyEquiv()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Set key shortcut and modifiers
+  nsAutoString keyValue;
+  mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::key, keyValue);
+  if (!keyValue.IsEmpty() && mContent->GetUncomposedDoc()) {
+    nsIContent *keyContent = mContent->GetUncomposedDoc()->GetElementById(keyValue);
+    if (keyContent) {
+      nsAutoString keyChar;
+      bool hasKey = keyContent->GetAttr(kNameSpaceID_None, nsGkAtoms::key, keyChar);
+
+      if (!hasKey || keyChar.IsEmpty()) {
+        nsAutoString keyCodeName;
+        keyContent->GetAttr(kNameSpaceID_None, nsGkAtoms::keycode, keyCodeName);
+        uint32_t charCode =
+          nsCocoaUtils::ConvertGeckoNameToMacCharCode(keyCodeName);
+        if (charCode) {
+          keyChar.Assign(charCode);
+        }
+        else {
+          keyChar.Assign(NS_LITERAL_STRING(" "));
+        }
+      }
+
+      nsAutoString modifiersStr;
+      keyContent->GetAttr(kNameSpaceID_None, nsGkAtoms::modifiers, modifiersStr);
+      uint8_t modifiers = nsMenuUtilsX::GeckoModifiersForNodeAttribute(modifiersStr);
+
+      unsigned int macModifiers = nsMenuUtilsX::MacModifiersForGeckoModifiers(modifiers);
+      [mNativeMenuItem setKeyEquivalentModifierMask:macModifiers];
+
+      NSString *keyEquivalent = [[NSString stringWithCharacters:(unichar*)keyChar.get()
+                                                         length:keyChar.Length()] lowercaseString];
+      if ([keyEquivalent isEqualToString:@" "])
+        [mNativeMenuItem setKeyEquivalent:@""];
+      else
+        [mNativeMenuItem setKeyEquivalent:keyEquivalent];
+
+      return;
+    }
+  }
+
+  // if the key was removed, clear the key
+  [mNativeMenuItem setKeyEquivalent:@""];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+//
+// nsChangeObserver
+//
+
+void
+nsMenuItemX::ObserveAttributeChanged(nsIDocument *aDocument, nsIContent *aContent, nsIAtom *aAttribute)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!aContent)
+    return;
+
+  if (aContent == mContent) { // our own content node changed
+    if (aAttribute == nsGkAtoms::checked) {
+      // if we're a radio menu, uncheck our sibling radio items. No need to
+      // do any of this if we're just a normal check menu.
+      if (mType == eRadioMenuItemType) {
+        if (mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::checked,
+                                  nsGkAtoms::_true, eCaseMatters))
+          UncheckRadioSiblings(mContent);
+      }
+      mMenuParent->SetRebuild(true);
+    }
+    else if (aAttribute == nsGkAtoms::hidden ||
+             aAttribute == nsGkAtoms::collapsed ||
+             aAttribute == nsGkAtoms::label) {
+      mMenuParent->SetRebuild(true);
+    }
+    else if (aAttribute == nsGkAtoms::key) {
+      SetKeyEquiv();
+    }
+    else if (aAttribute == nsGkAtoms::image) {
+      SetupIcon();
+    }
+    else if (aAttribute == nsGkAtoms::disabled) {
+      if (aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled, nsGkAtoms::_true, eCaseMatters))
+        [mNativeMenuItem setEnabled:NO];
+      else
+        [mNativeMenuItem setEnabled:YES];
+    }
+  }
+  else if (aContent == mCommandContent) {
+    // the only thing that really matters when the menu isn't showing is the
+    // enabled state since it enables/disables keyboard commands
+    if (aAttribute == nsGkAtoms::disabled) {
+      // first we sync our menu item DOM node with the command DOM node
+      nsAutoString commandDisabled;
+      nsAutoString menuDisabled;
+      aContent->GetAttr(kNameSpaceID_None, nsGkAtoms::disabled, commandDisabled);
+      mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::disabled, menuDisabled);
+      if (!commandDisabled.Equals(menuDisabled)) {
+        // The menu's disabled state needs to be updated to match the command.
+        if (commandDisabled.IsEmpty())
+          mContent->UnsetAttr(kNameSpaceID_None, nsGkAtoms::disabled, true);
+        else
+          mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::disabled, commandDisabled, true);
+      }
+      // now we sync our native menu item with the command DOM node
+      if (aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled, nsGkAtoms::_true, eCaseMatters))
+        [mNativeMenuItem setEnabled:NO];
+      else
+        [mNativeMenuItem setEnabled:YES];
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsMenuItemX::ObserveContentRemoved(nsIDocument *aDocument, nsIContent *aChild, int32_t aIndexInContainer)
+{
+  if (aChild == mCommandContent) {
+    mMenuGroupOwner->UnregisterForContentChanges(mCommandContent);
+    mCommandContent = nullptr;
+  }
+
+  mMenuParent->SetRebuild(true);
+}
+
+void nsMenuItemX::ObserveContentInserted(nsIDocument *aDocument, nsIContent* aContainer,
+                                         nsIContent *aChild)
+{
+  mMenuParent->SetRebuild(true);
+}
+
+void nsMenuItemX::SetupIcon()
+{
+  if (mIcon)
+    mIcon->SetupIcon();
+}
diff --git a/widget/cocoa/nsMenuUtilsX.h b/widget/cocoa/nsMenuUtilsX.h
new file mode 100644
index 0000000000..1571cdfb0a
--- /dev/null
+++ b/widget/cocoa/nsMenuUtilsX.h
@@ -0,0 +1,31 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsMenuUtilsX_h_
+#define nsMenuUtilsX_h_
+
+#include "nscore.h"
+#include "nsMenuBaseX.h"
+
+#import <Cocoa/Cocoa.h>
+
+class nsIContent;
+class nsString;
+class nsMenuBarX;
+
+// Namespace containing utility functions used in our native menu implementation.
+namespace nsMenuUtilsX
+{
+  void          DispatchCommandTo(nsIContent* aTargetContent);
+  NSString*     GetTruncatedCocoaLabel(const nsString& itemLabel);
+  uint8_t       GeckoModifiersForNodeAttribute(const nsString& modifiersAttribute);
+  unsigned int  MacModifiersForGeckoModifiers(uint8_t geckoModifiers);
+  nsMenuBarX*   GetHiddenWindowMenuBar(); // returned object is not retained
+  NSMenuItem*   GetStandardEditMenuItem(); // returned object is not retained
+  bool          NodeIsHiddenOrCollapsed(nsIContent* inContent);
+  int           CalculateNativeInsertionPoint(nsMenuObjectX* aParent, nsMenuObjectX* aChild);
+} // namespace nsMenuUtilsX
+
+#endif // nsMenuUtilsX_h_
diff --git a/widget/cocoa/nsMenuUtilsX.mm b/widget/cocoa/nsMenuUtilsX.mm
new file mode 100644
index 0000000000..db64717127
--- /dev/null
+++ b/widget/cocoa/nsMenuUtilsX.mm
@@ -0,0 +1,223 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/Event.h"
+#include "nsMenuUtilsX.h"
+#include "nsMenuBarX.h"
+#include "nsMenuX.h"
+#include "nsMenuItemX.h"
+#include "nsStandaloneNativeMenu.h"
+#include "nsObjCExceptions.h"
+#include "nsCocoaUtils.h"
+#include "nsCocoaWindow.h"
+#include "nsGkAtoms.h"
+#include "nsIDocument.h"
+#include "nsIDOMDocument.h"
+#include "nsIDOMXULCommandEvent.h"
+#include "nsPIDOMWindow.h"
+#include "nsQueryObject.h"
+
+using namespace mozilla;
+
+void nsMenuUtilsX::DispatchCommandTo(nsIContent* aTargetContent)
+{
+  NS_PRECONDITION(aTargetContent, "null ptr");
+
+  nsIDocument* doc = aTargetContent->OwnerDoc();
+  if (doc) {
+    ErrorResult rv;
+    RefPtr<dom::Event> event =
+      doc->CreateEvent(NS_LITERAL_STRING("xulcommandevent"), rv);
+    nsCOMPtr<nsIDOMXULCommandEvent> command = do_QueryObject(event);
+
+    // FIXME: Should probably figure out how to init this with the actual
+    // pressed keys, but this is a big old edge case anyway. -dwh
+    if (command &&
+        NS_SUCCEEDED(command->InitCommandEvent(NS_LITERAL_STRING("command"),
+                                               true, true,
+                                               doc->GetInnerWindow(), 0,
+                                               false, false, false,
+                                               false, nullptr))) {
+      event->SetTrusted(true);
+      bool dummy;
+      aTargetContent->DispatchEvent(event, &dummy);
+    }
+  }
+}
+
+NSString* nsMenuUtilsX::GetTruncatedCocoaLabel(const nsString& itemLabel)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  // We want to truncate long strings to some reasonable pixel length but there is no
+  // good API for doing that which works for all OS versions and architectures. For now
+  // we'll do nothing for consistency and depend on good user interface design to limit
+  // string lengths.
+  return [NSString stringWithCharacters:reinterpret_cast<const unichar*>(itemLabel.get())
+                                 length:itemLabel.Length()];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+uint8_t nsMenuUtilsX::GeckoModifiersForNodeAttribute(const nsString& modifiersAttribute)
+{
+  uint8_t modifiers = knsMenuItemNoModifier;
+  char* str = ToNewCString(modifiersAttribute);
+  char* newStr;
+  char* token = strtok_r(str, ", \t", &newStr);
+  while (token != NULL) {
+    if (strcmp(token, "shift") == 0)
+      modifiers |= knsMenuItemShiftModifier;
+    else if (strcmp(token, "alt") == 0) 
+      modifiers |= knsMenuItemAltModifier;
+    else if (strcmp(token, "control") == 0) 
+      modifiers |= knsMenuItemControlModifier;
+    else if ((strcmp(token, "accel") == 0) ||
+             (strcmp(token, "meta") == 0)) {
+      modifiers |= knsMenuItemCommandModifier;
+    }
+    token = strtok_r(newStr, ", \t", &newStr);
+  }
+  free(str);
+
+  return modifiers;
+}
+
+unsigned int nsMenuUtilsX::MacModifiersForGeckoModifiers(uint8_t geckoModifiers)
+{
+  unsigned int macModifiers = 0;
+  
+  if (geckoModifiers & knsMenuItemShiftModifier)
+    macModifiers |= NSShiftKeyMask;
+  if (geckoModifiers & knsMenuItemAltModifier)
+    macModifiers |= NSAlternateKeyMask;
+  if (geckoModifiers & knsMenuItemControlModifier)
+    macModifiers |= NSControlKeyMask;
+  if (geckoModifiers & knsMenuItemCommandModifier)
+    macModifiers |= NSCommandKeyMask;
+
+  return macModifiers;
+}
+
+nsMenuBarX* nsMenuUtilsX::GetHiddenWindowMenuBar()
+{
+  nsIWidget* hiddenWindowWidgetNoCOMPtr = nsCocoaUtils::GetHiddenWindowWidget();
+  if (hiddenWindowWidgetNoCOMPtr)
+    return static_cast<nsCocoaWindow*>(hiddenWindowWidgetNoCOMPtr)->GetMenuBar();
+  else
+    return nullptr;
+}
+
+// It would be nice if we could localize these edit menu names.
+NSMenuItem* nsMenuUtilsX::GetStandardEditMenuItem()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  // In principle we should be able to allocate this once and then always
+  // return the same object.  But weird interactions happen between native
+  // app-modal dialogs and Gecko-modal dialogs that open above them.  So what
+  // we return here isn't always released before it needs to be added to
+  // another menu.  See bmo bug 468393.
+  NSMenuItem* standardEditMenuItem =
+    [[[NSMenuItem alloc] initWithTitle:@"Edit" action:nil keyEquivalent:@""] autorelease];
+  NSMenu* standardEditMenu = [[NSMenu alloc] initWithTitle:@"Edit"];
+  [standardEditMenuItem setSubmenu:standardEditMenu];
+  [standardEditMenu release];
+
+  // Add Undo
+  NSMenuItem* undoItem = [[NSMenuItem alloc] initWithTitle:@"Undo" action:@selector(undo:) keyEquivalent:@"z"];
+  [standardEditMenu addItem:undoItem];
+  [undoItem release];
+
+  // Add Redo
+  NSMenuItem* redoItem = [[NSMenuItem alloc] initWithTitle:@"Redo" action:@selector(redo:) keyEquivalent:@"Z"];
+  [standardEditMenu addItem:redoItem];
+  [redoItem release];
+
+  // Add separator
+  [standardEditMenu addItem:[NSMenuItem separatorItem]];
+
+  // Add Cut
+  NSMenuItem* cutItem = [[NSMenuItem alloc] initWithTitle:@"Cut" action:@selector(cut:) keyEquivalent:@"x"];
+  [standardEditMenu addItem:cutItem];
+  [cutItem release];
+
+  // Add Copy
+  NSMenuItem* copyItem = [[NSMenuItem alloc] initWithTitle:@"Copy" action:@selector(copy:) keyEquivalent:@"c"];
+  [standardEditMenu addItem:copyItem];
+  [copyItem release];
+
+  // Add Paste
+  NSMenuItem* pasteItem = [[NSMenuItem alloc] initWithTitle:@"Paste" action:@selector(paste:) keyEquivalent:@"v"];
+  [standardEditMenu addItem:pasteItem];
+  [pasteItem release];
+
+  // Add Delete
+  NSMenuItem* deleteItem = [[NSMenuItem alloc] initWithTitle:@"Delete" action:@selector(delete:) keyEquivalent:@""];
+  [standardEditMenu addItem:deleteItem];
+  [deleteItem release];
+
+  // Add Select All
+  NSMenuItem* selectAllItem = [[NSMenuItem alloc] initWithTitle:@"Select All" action:@selector(selectAll:) keyEquivalent:@"a"];
+  [standardEditMenu addItem:selectAllItem];
+  [selectAllItem release];
+
+  return standardEditMenuItem;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+bool nsMenuUtilsX::NodeIsHiddenOrCollapsed(nsIContent* inContent)
+{
+  return (inContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::hidden,
+                                 nsGkAtoms::_true, eCaseMatters) ||
+          inContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::collapsed,
+                                 nsGkAtoms::_true, eCaseMatters));
+}
+
+// Determines how many items are visible among the siblings in a menu that are
+// before the given child. This will not count the application menu.
+int nsMenuUtilsX::CalculateNativeInsertionPoint(nsMenuObjectX* aParent,
+                                                nsMenuObjectX* aChild)
+{
+  int insertionPoint = 0;
+  nsMenuObjectTypeX parentType = aParent->MenuObjectType();
+  if (parentType == eMenuBarObjectType) {
+    nsMenuBarX* menubarParent = static_cast<nsMenuBarX*>(aParent);
+    uint32_t numMenus = menubarParent->GetMenuCount();
+    for (uint32_t i = 0; i < numMenus; i++) {
+      nsMenuX* currMenu = menubarParent->GetMenuAt(i);
+      if (currMenu == aChild)
+        return insertionPoint; // we found ourselves, break out
+      if (currMenu && [currMenu->NativeMenuItem() menu])
+        insertionPoint++;
+    }
+  }
+  else if (parentType == eSubmenuObjectType ||
+           parentType == eStandaloneNativeMenuObjectType) {
+    nsMenuX* menuParent;
+    if (parentType == eSubmenuObjectType)
+      menuParent = static_cast<nsMenuX*>(aParent);
+    else
+      menuParent = static_cast<nsStandaloneNativeMenu*>(aParent)->GetMenuXObject();
+
+    uint32_t numItems = menuParent->GetItemCount();
+    for (uint32_t i = 0; i < numItems; i++) {
+      // Using GetItemAt instead of GetVisibleItemAt to avoid O(N^2)
+      nsMenuObjectX* currItem = menuParent->GetItemAt(i);
+      if (currItem == aChild)
+        return insertionPoint; // we found ourselves, break out
+      NSMenuItem* nativeItem = nil;
+      nsMenuObjectTypeX currItemType = currItem->MenuObjectType();
+      if (currItemType == eSubmenuObjectType)
+        nativeItem = static_cast<nsMenuX*>(currItem)->NativeMenuItem();
+      else
+        nativeItem = (NSMenuItem*)(currItem->NativeData());
+      if ([nativeItem menu])
+        insertionPoint++;
+    }
+  }
+  return insertionPoint;
+}
diff --git a/widget/cocoa/nsMenuX.h b/widget/cocoa/nsMenuX.h
new file mode 100644
index 0000000000..7b5146a0b8
--- /dev/null
+++ b/widget/cocoa/nsMenuX.h
@@ -0,0 +1,101 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsMenuX_h_
+#define nsMenuX_h_
+
+#import <Cocoa/Cocoa.h>
+
+#include "mozilla/RefPtr.h"
+#include "mozilla/UniquePtr.h"
+#include "nsMenuBaseX.h"
+#include "nsMenuBarX.h"
+#include "nsMenuGroupOwnerX.h"
+#include "nsCOMPtr.h"
+#include "nsChangeObserver.h"
+
+class nsMenuX;
+class nsMenuItemIconX;
+class nsMenuItemX;
+class nsIWidget;
+
+// MenuDelegate is used to receive Cocoa notifications for setting
+// up carbon events. Protocol is defined as of 10.6 SDK.
+@interface MenuDelegate : NSObject < NSMenuDelegate >
+{
+  nsMenuX* mGeckoMenu; // weak ref
+}
+- (id)initWithGeckoMenu:(nsMenuX*)geckoMenu;
+@end
+
+// Once instantiated, this object lives until its DOM node or its parent window is destroyed.
+// Do not hold references to this, they can become invalid any time the DOM node can be destroyed.
+class nsMenuX : public nsMenuObjectX,
+                public nsChangeObserver
+{
+public:
+  nsMenuX();
+  virtual ~nsMenuX();
+
+  // If > 0, the OS is indexing all the app's menus (triggered by opening
+  // Help menu on Leopard and higher).  There are some things that are
+  // unsafe to do while this is happening.
+  static int32_t sIndexingMenuLevel;
+
+  NS_DECL_CHANGEOBSERVER
+
+  // nsMenuObjectX
+  void*             NativeData() override {return (void*)mNativeMenu;}
+  nsMenuObjectTypeX MenuObjectType() override {return eSubmenuObjectType;}
+  void              IconUpdated() override { mParent->IconUpdated(); }
+
+  // nsMenuX
+  nsresult       Create(nsMenuObjectX* aParent, nsMenuGroupOwnerX* aMenuGroupOwner, nsIContent* aNode);
+  uint32_t       GetItemCount();
+  nsMenuObjectX* GetItemAt(uint32_t aPos);
+  nsresult       GetVisibleItemCount(uint32_t &aCount);
+  nsMenuObjectX* GetVisibleItemAt(uint32_t aPos);
+  nsEventStatus  MenuOpened();
+  void           MenuClosed();
+  void           SetRebuild(bool aMenuEvent);
+  NSMenuItem*    NativeMenuItem();
+  nsresult       SetupIcon();
+
+  static bool    IsXULHelpMenu(nsIContent* aMenuContent);
+
+protected:
+  void           MenuConstruct();
+  nsresult       RemoveAll();
+  nsresult       SetEnabled(bool aIsEnabled);
+  nsresult       GetEnabled(bool* aIsEnabled);
+  void           GetMenuPopupContent(nsIContent** aResult);
+  bool           OnOpen();
+  bool           OnClose();
+  nsresult       AddMenuItem(nsMenuItemX* aMenuItem);
+  nsMenuX*       AddMenu(mozilla::UniquePtr<nsMenuX> aMenu);
+  void           LoadMenuItem(nsIContent* inMenuItemContent);
+  void           LoadSubMenu(nsIContent* inMenuContent);
+  GeckoNSMenu*   CreateMenuWithGeckoString(nsString& menuTitle);
+
+  nsTArray<mozilla::UniquePtr<nsMenuObjectX>> mMenuObjectsArray;
+  nsString                  mLabel;
+  uint32_t                  mVisibleItemsCount; // cache
+  nsMenuObjectX*            mParent; // [weak]
+  nsMenuGroupOwnerX*        mMenuGroupOwner; // [weak]
+  // The icon object should never outlive its creating nsMenuX object.
+  RefPtr<nsMenuItemIconX> mIcon;
+  GeckoNSMenu*              mNativeMenu; // [strong]
+  MenuDelegate*             mMenuDelegate; // [strong]
+  // nsMenuX objects should always have a valid native menu item.
+  NSMenuItem*               mNativeMenuItem; // [strong]
+  bool                      mIsEnabled;
+  bool                      mDestroyHandlerCalled;
+  bool                      mNeedsRebuild;
+  bool                      mConstructed;
+  bool                      mVisible;
+  bool                      mXBLAttached;
+};
+
+#endif // nsMenuX_h_
diff --git a/widget/cocoa/nsMenuX.mm b/widget/cocoa/nsMenuX.mm
new file mode 100644
index 0000000000..757221eac6
--- /dev/null
+++ b/widget/cocoa/nsMenuX.mm
@@ -0,0 +1,1051 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <dlfcn.h>
+
+#include "nsMenuX.h"
+#include "nsMenuItemX.h"
+#include "nsMenuUtilsX.h"
+#include "nsMenuItemIconX.h"
+#include "nsStandaloneNativeMenu.h"
+
+#include "nsObjCExceptions.h"
+
+#include "nsToolkit.h"
+#include "nsCocoaUtils.h"
+#include "nsCOMPtr.h"
+#include "prinrval.h"
+#include "nsString.h"
+#include "nsReadableUtils.h"
+#include "nsUnicharUtils.h"
+#include "plstr.h"
+#include "nsGkAtoms.h"
+#include "nsCRT.h"
+#include "nsBaseWidget.h"
+
+#include "nsIDocument.h"
+#include "nsIContent.h"
+#include "nsIDOMDocument.h"
+#include "nsIDocumentObserver.h"
+#include "nsIComponentManager.h"
+#include "nsIRollupListener.h"
+#include "nsIDOMElement.h"
+#include "nsBindingManager.h"
+#include "nsIServiceManager.h"
+#include "nsXULPopupManager.h"
+#include "mozilla/dom/ScriptSettings.h"
+
+#include "jsapi.h"
+#include "nsIScriptGlobalObject.h"
+#include "nsIScriptContext.h"
+#include "nsIXPConnect.h"
+
+#include "mozilla/MouseEvents.h"
+
+using namespace mozilla;
+
+static bool gConstructingMenu = false;
+static bool gMenuMethodsSwizzled = false;
+
+int32_t nsMenuX::sIndexingMenuLevel = 0;
+
+
+//
+// Objective-C class used for representedObject
+//
+
+@implementation MenuItemInfo
+
+- (id) initWithMenuGroupOwner:(nsMenuGroupOwnerX *)aMenuGroupOwner
+{
+  if ((self = [super init]) != nil) {
+    [self setMenuGroupOwner:aMenuGroupOwner];
+  }
+  return self;
+}
+
+- (void) dealloc
+{
+  [self setMenuGroupOwner:nullptr];
+  [super dealloc];
+}
+
+- (nsMenuGroupOwnerX *) menuGroupOwner
+{
+  return mMenuGroupOwner;
+}
+
+- (void) setMenuGroupOwner:(nsMenuGroupOwnerX *)aMenuGroupOwner
+{
+  // weak reference as the nsMenuGroupOwnerX owns all of its sub-objects
+  mMenuGroupOwner = aMenuGroupOwner;
+  if (aMenuGroupOwner) {
+    aMenuGroupOwner->AddMenuItemInfoToSet(self);
+  }
+}
+
+@end
+
+
+//
+// nsMenuX
+//
+
+nsMenuX::nsMenuX()
+: mVisibleItemsCount(0), mParent(nullptr), mMenuGroupOwner(nullptr),
+  mNativeMenu(nil), mNativeMenuItem(nil), mIsEnabled(true),
+  mDestroyHandlerCalled(false), mNeedsRebuild(true),
+  mConstructed(false), mVisible(true), mXBLAttached(false)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!gMenuMethodsSwizzled) {
+    nsToolkit::SwizzleMethods([NSMenu class], @selector(_addItem:toTable:),
+                              @selector(nsMenuX_NSMenu_addItem:toTable:), true);
+    nsToolkit::SwizzleMethods([NSMenu class], @selector(_removeItem:fromTable:),
+                              @selector(nsMenuX_NSMenu_removeItem:fromTable:), true);
+    // On SnowLeopard the Shortcut framework (which contains the
+    // SCTGRLIndex class) is loaded on demand, whenever the user first opens
+    // a menu (which normally hasn't happened yet).  So we need to load it
+    // here explicitly.
+    dlopen("/System/Library/PrivateFrameworks/Shortcut.framework/Shortcut", RTLD_LAZY);
+    Class SCTGRLIndexClass = ::NSClassFromString(@"SCTGRLIndex");
+    nsToolkit::SwizzleMethods(SCTGRLIndexClass, @selector(indexMenuBarDynamically),
+                              @selector(nsMenuX_SCTGRLIndex_indexMenuBarDynamically));
+
+    gMenuMethodsSwizzled = true;
+  }
+
+  mMenuDelegate = [[MenuDelegate alloc] initWithGeckoMenu:this];
+
+  if (!nsMenuBarX::sNativeEventTarget)
+    nsMenuBarX::sNativeEventTarget = [[NativeMenuItemTarget alloc] init];
+
+  MOZ_COUNT_CTOR(nsMenuX);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsMenuX::~nsMenuX()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Prevent the icon object from outliving us.
+  if (mIcon)
+    mIcon->Destroy();
+
+  RemoveAll();
+
+  [mNativeMenu setDelegate:nil];
+  [mNativeMenu release];
+  [mMenuDelegate release];
+  // autorelease the native menu item so that anything else happening to this
+  // object happens before the native menu item actually dies
+  [mNativeMenuItem autorelease];
+
+  // alert the change notifier we don't care no more
+  if (mContent)
+    mMenuGroupOwner->UnregisterForContentChanges(mContent);
+
+  MOZ_COUNT_DTOR(nsMenuX);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsresult nsMenuX::Create(nsMenuObjectX* aParent, nsMenuGroupOwnerX* aMenuGroupOwner, nsIContent* aNode)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  mContent = aNode;
+  mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::label, mLabel);
+  mNativeMenu = CreateMenuWithGeckoString(mLabel);
+
+  // register this menu to be notified when changes are made to our content object
+  mMenuGroupOwner = aMenuGroupOwner; // weak ref
+  NS_ASSERTION(mMenuGroupOwner, "No menu owner given, must have one");
+  mMenuGroupOwner->RegisterForContentChanges(mContent, this);
+
+  mParent = aParent;
+  // our parent could be either a menu bar (if we're toplevel) or a menu (if we're a submenu)
+
+#ifdef DEBUG
+  nsMenuObjectTypeX parentType =
+#endif
+    mParent->MenuObjectType();
+  NS_ASSERTION((parentType == eMenuBarObjectType || parentType == eSubmenuObjectType || parentType == eStandaloneNativeMenuObjectType),
+               "Menu parent not a menu bar, menu, or native menu!");
+
+  if (nsMenuUtilsX::NodeIsHiddenOrCollapsed(mContent))
+    mVisible = false;
+  if (mContent->GetChildCount() == 0)
+    mVisible = false;
+
+  NSString *newCocoaLabelString = nsMenuUtilsX::GetTruncatedCocoaLabel(mLabel);
+  mNativeMenuItem = [[NSMenuItem alloc] initWithTitle:newCocoaLabelString action:nil keyEquivalent:@""];
+  [mNativeMenuItem setSubmenu:mNativeMenu];
+
+  SetEnabled(!mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled,
+                                    nsGkAtoms::_true, eCaseMatters));
+
+  // We call MenuConstruct here because keyboard commands are dependent upon
+  // native menu items being created. If we only call MenuConstruct when a menu
+  // is actually selected, then we can't access keyboard commands until the
+  // menu gets selected, which is bad.
+  MenuConstruct();
+
+  mIcon = new nsMenuItemIconX(this, mContent, mNativeMenuItem);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult nsMenuX::AddMenuItem(nsMenuItemX* aMenuItem)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (!aMenuItem)
+    return NS_ERROR_INVALID_ARG;
+
+  mMenuObjectsArray.AppendElement(aMenuItem);
+  if (nsMenuUtilsX::NodeIsHiddenOrCollapsed(aMenuItem->Content()))
+    return NS_OK;
+  ++mVisibleItemsCount;
+
+  NSMenuItem* newNativeMenuItem = (NSMenuItem*)aMenuItem->NativeData();
+
+  // add the menu item to this menu
+  [mNativeMenu addItem:newNativeMenuItem];
+
+  // set up target/action
+  [newNativeMenuItem setTarget:nsMenuBarX::sNativeEventTarget];
+  [newNativeMenuItem setAction:@selector(menuItemHit:)];
+
+  // set its command. we get the unique command id from the menubar
+  [newNativeMenuItem setTag:mMenuGroupOwner->RegisterForCommand(aMenuItem)];
+  MenuItemInfo * info = [[MenuItemInfo alloc] initWithMenuGroupOwner:mMenuGroupOwner];
+  [newNativeMenuItem setRepresentedObject:info];
+  [info release];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsMenuX* nsMenuX::AddMenu(UniquePtr<nsMenuX> aMenu)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  // aMenu transfers ownership to mMenuObjectsArray and becomes nullptr, so
+  // we need to keep a raw pointer to access it conveniently.
+  nsMenuX* menu = aMenu.get();
+  mMenuObjectsArray.AppendElement(Move(aMenu));
+
+  if (nsMenuUtilsX::NodeIsHiddenOrCollapsed(menu->Content())) {
+    return menu;
+  }
+
+  ++mVisibleItemsCount;
+
+  // We have to add a menu item and then associate the menu with it
+  NSMenuItem* newNativeMenuItem = menu->NativeMenuItem();
+  if (newNativeMenuItem) {
+    [mNativeMenu addItem:newNativeMenuItem];
+    [newNativeMenuItem setSubmenu:(NSMenu*)menu->NativeData()];
+  }
+
+  return menu;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(nullptr);
+}
+
+// Includes all items, including hidden/collapsed ones
+uint32_t nsMenuX::GetItemCount()
+{
+  return mMenuObjectsArray.Length();
+}
+
+// Includes all items, including hidden/collapsed ones
+nsMenuObjectX* nsMenuX::GetItemAt(uint32_t aPos)
+{
+  if (aPos >= (uint32_t)mMenuObjectsArray.Length())
+    return NULL;
+
+  return mMenuObjectsArray[aPos].get();
+}
+
+// Only includes visible items
+nsresult nsMenuX::GetVisibleItemCount(uint32_t &aCount)
+{
+  aCount = mVisibleItemsCount;
+  return NS_OK;
+}
+
+// Only includes visible items. Note that this is provides O(N) access
+// If you need to iterate or search, consider using GetItemAt and doing your own filtering
+nsMenuObjectX* nsMenuX::GetVisibleItemAt(uint32_t aPos)
+{
+
+  uint32_t count = mMenuObjectsArray.Length();
+  if (aPos >= mVisibleItemsCount || aPos >= count)
+    return NULL;
+
+  // If there are no invisible items, can provide direct access
+  if (mVisibleItemsCount == count)
+    return mMenuObjectsArray[aPos].get();
+
+  // Otherwise, traverse the array until we find the the item we're looking for.
+  nsMenuObjectX* item;
+  uint32_t visibleNodeIndex = 0;
+  for (uint32_t i = 0; i < count; i++) {
+    item = mMenuObjectsArray[i].get();
+    if (!nsMenuUtilsX::NodeIsHiddenOrCollapsed(item->Content())) {
+      if (aPos == visibleNodeIndex) {
+        // we found the visible node we're looking for, return it
+        return item;
+      }
+      visibleNodeIndex++;
+    }
+  }
+
+  return NULL;
+}
+
+nsresult nsMenuX::RemoveAll()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (mNativeMenu) {
+    // clear command id's
+    int itemCount = [mNativeMenu numberOfItems];
+    for (int i = 0; i < itemCount; i++)
+      mMenuGroupOwner->UnregisterCommand((uint32_t)[[mNativeMenu itemAtIndex:i] tag]);
+    // get rid of Cocoa menu items
+    for (int i = [mNativeMenu numberOfItems] - 1; i >= 0; i--)
+      [mNativeMenu removeItemAtIndex:i];
+  }
+
+  mMenuObjectsArray.Clear();
+  mVisibleItemsCount = 0;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsEventStatus nsMenuX::MenuOpened()
+{
+  // Open the node.
+  mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::open, NS_LITERAL_STRING("true"), true);
+
+  // Fire a handler. If we're told to stop, don't build the menu at all
+  bool keepProcessing = OnOpen();
+
+  if (!mNeedsRebuild || !keepProcessing)
+    return nsEventStatus_eConsumeNoDefault;
+
+  if (!mConstructed || mNeedsRebuild) {
+    if (mNeedsRebuild)
+      RemoveAll();
+
+    MenuConstruct();
+    mConstructed = true;
+  }
+
+  nsEventStatus status = nsEventStatus_eIgnore;
+  WidgetMouseEvent event(true, eXULPopupShown, nullptr,
+                         WidgetMouseEvent::eReal);
+
+  nsCOMPtr<nsIContent> popupContent;
+  GetMenuPopupContent(getter_AddRefs(popupContent));
+  nsIContent* dispatchTo = popupContent ? popupContent : mContent;
+  dispatchTo->DispatchDOMEvent(&event, nullptr, nullptr, &status);
+
+  return nsEventStatus_eConsumeNoDefault;
+}
+
+void nsMenuX::MenuClosed()
+{
+  if (mConstructed) {
+    // Don't close if a handler tells us to stop.
+    if (!OnClose())
+      return;
+
+    if (mNeedsRebuild)
+      mConstructed = false;
+
+    mContent->UnsetAttr(kNameSpaceID_None, nsGkAtoms::open, true);
+
+    nsEventStatus status = nsEventStatus_eIgnore;
+    WidgetMouseEvent event(true, eXULPopupHidden, nullptr,
+                           WidgetMouseEvent::eReal);
+
+    nsCOMPtr<nsIContent> popupContent;
+    GetMenuPopupContent(getter_AddRefs(popupContent));
+    nsIContent* dispatchTo = popupContent ? popupContent : mContent;
+    dispatchTo->DispatchDOMEvent(&event, nullptr, nullptr, &status);
+
+    mDestroyHandlerCalled = true;
+    mConstructed = false;
+  }
+}
+
+void nsMenuX::MenuConstruct()
+{
+  mConstructed = false;
+  gConstructingMenu = true;
+
+  // reset destroy handler flag so that we'll know to fire it next time this menu goes away.
+  mDestroyHandlerCalled = false;
+
+  //printf("nsMenuX::MenuConstruct called for %s = %d \n", NS_LossyConvertUTF16toASCII(mLabel).get(), mNativeMenu);
+
+  // Retrieve our menupopup.
+  nsCOMPtr<nsIContent> menuPopup;
+  GetMenuPopupContent(getter_AddRefs(menuPopup));
+  if (!menuPopup) {
+    gConstructingMenu = false;
+    return;
+  }
+
+  // bug 365405: Manually wrap the menupopup node to make sure it's bounded
+  if (!mXBLAttached) {
+    nsresult rv;
+    nsCOMPtr<nsIXPConnect> xpconnect =
+      do_GetService(nsIXPConnect::GetCID(), &rv);
+    if (NS_SUCCEEDED(rv)) {
+      nsIDocument* ownerDoc = menuPopup->OwnerDoc();
+      dom::AutoJSAPI jsapi;
+      if (ownerDoc && jsapi.Init(ownerDoc->GetInnerWindow())) {
+        JSContext* cx = jsapi.cx();
+        JS::RootedObject ignoredObj(cx);
+        xpconnect->WrapNative(cx, JS::CurrentGlobalOrNull(cx), menuPopup,
+                              NS_GET_IID(nsISupports), ignoredObj.address());
+        mXBLAttached = true;
+      }
+    }
+  }
+
+  // Iterate over the kids
+  uint32_t count = menuPopup->GetChildCount();
+  for (uint32_t i = 0; i < count; i++) {
+    nsIContent *child = menuPopup->GetChildAt(i);
+    if (child) {
+      // depending on the type, create a menu item, separator, or submenu
+      if (child->IsAnyOfXULElements(nsGkAtoms::menuitem,
+                                    nsGkAtoms::menuseparator)) {
+        LoadMenuItem(child);
+      } else if (child->IsXULElement(nsGkAtoms::menu)) {
+        LoadSubMenu(child);
+      }
+    }
+  } // for each menu item
+
+  gConstructingMenu = false;
+  mNeedsRebuild = false;
+  // printf("Done building, mMenuObjectsArray.Count() = %d \n", mMenuObjectsArray.Count());
+}
+
+void nsMenuX::SetRebuild(bool aNeedsRebuild)
+{
+  if (!gConstructingMenu)
+    mNeedsRebuild = aNeedsRebuild;
+}
+
+nsresult nsMenuX::SetEnabled(bool aIsEnabled)
+{
+  if (aIsEnabled != mIsEnabled) {
+    // we always want to rebuild when this changes
+    mIsEnabled = aIsEnabled;
+    [mNativeMenuItem setEnabled:(BOOL)mIsEnabled];
+  }
+  return NS_OK;
+}
+
+nsresult nsMenuX::GetEnabled(bool* aIsEnabled)
+{
+  NS_ENSURE_ARG_POINTER(aIsEnabled);
+  *aIsEnabled = mIsEnabled;
+  return NS_OK;
+}
+
+GeckoNSMenu* nsMenuX::CreateMenuWithGeckoString(nsString& menuTitle)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  NSString* title = [NSString stringWithCharacters:(UniChar*)menuTitle.get() length:menuTitle.Length()];
+  GeckoNSMenu* myMenu = [[GeckoNSMenu alloc] initWithTitle:title];
+  [myMenu setDelegate:mMenuDelegate];
+
+  // We don't want this menu to auto-enable menu items because then Cocoa
+  // overrides our decisions and things get incorrectly enabled/disabled.
+  [myMenu setAutoenablesItems:NO];
+
+  // we used to install Carbon event handlers here, but since NSMenu* doesn't
+  // create its underlying MenuRef until just before display, we delay until
+  // that happens. Now we install the event handlers when Cocoa notifies
+  // us that a menu is about to display - see the Cocoa MenuDelegate class.
+
+  return myMenu;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+void nsMenuX::LoadMenuItem(nsIContent* inMenuItemContent)
+{
+  if (!inMenuItemContent)
+    return;
+
+  nsAutoString menuitemName;
+  inMenuItemContent->GetAttr(kNameSpaceID_None, nsGkAtoms::label, menuitemName);
+
+  // printf("menuitem %s \n", NS_LossyConvertUTF16toASCII(menuitemName).get());
+
+  EMenuItemType itemType = eRegularMenuItemType;
+  if (inMenuItemContent->IsXULElement(nsGkAtoms::menuseparator)) {
+    itemType = eSeparatorMenuItemType;
+  }
+  else {
+    static nsIContent::AttrValuesArray strings[] =
+  {&nsGkAtoms::checkbox, &nsGkAtoms::radio, nullptr};
+    switch (inMenuItemContent->FindAttrValueIn(kNameSpaceID_None, nsGkAtoms::type,
+                                               strings, eCaseMatters)) {
+      case 0: itemType = eCheckboxMenuItemType; break;
+      case 1: itemType = eRadioMenuItemType; break;
+    }
+  }
+
+  // Create the item.
+  nsMenuItemX* menuItem = new nsMenuItemX();
+  if (!menuItem)
+    return;
+
+  nsresult rv = menuItem->Create(this, menuitemName, itemType, mMenuGroupOwner, inMenuItemContent);
+  if (NS_FAILED(rv)) {
+    delete menuItem;
+    return;
+  }
+
+  AddMenuItem(menuItem);
+
+  // This needs to happen after the nsIMenuItem object is inserted into
+  // our item array in AddMenuItem()
+  menuItem->SetupIcon();
+}
+
+void nsMenuX::LoadSubMenu(nsIContent* inMenuContent)
+{
+  auto menu = MakeUnique<nsMenuX>();
+  if (!menu)
+    return;
+
+  nsresult rv = menu->Create(this, mMenuGroupOwner, inMenuContent);
+  if (NS_FAILED(rv))
+    return;
+
+  // |menu|'s ownership is transfer to AddMenu but, if it is successfully
+  // added, we can access it via the returned raw pointer.
+  nsMenuX* menu_ptr = AddMenu(Move(menu));
+
+  // This needs to happen after the nsIMenu object is inserted into
+  // our item array in AddMenu()
+  if (menu_ptr) {
+    menu_ptr->SetupIcon();
+  }
+}
+
+// This menu is about to open. Returns TRUE if we should keep processing the event,
+// FALSE if the handler wants to stop the opening of the menu.
+bool nsMenuX::OnOpen()
+{
+  nsEventStatus status = nsEventStatus_eIgnore;
+  WidgetMouseEvent event(true, eXULPopupShowing, nullptr,
+                         WidgetMouseEvent::eReal);
+
+  nsCOMPtr<nsIContent> popupContent;
+  GetMenuPopupContent(getter_AddRefs(popupContent));
+
+  nsresult rv = NS_OK;
+  nsIContent* dispatchTo = popupContent ? popupContent : mContent;
+  rv = dispatchTo->DispatchDOMEvent(&event, nullptr, nullptr, &status);
+  if (NS_FAILED(rv) || status == nsEventStatus_eConsumeNoDefault)
+    return false;
+
+  // If the open is going to succeed we need to walk our menu items, checking to
+  // see if any of them have a command attribute. If so, several attributes
+  // must potentially be updated.
+
+  // Get new popup content first since it might have changed as a result of the
+  // eXULPopupShowing event above.
+  GetMenuPopupContent(getter_AddRefs(popupContent));
+  if (!popupContent)
+    return true;
+
+  nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
+  if (pm) {
+    pm->UpdateMenuItems(popupContent);
+  }
+
+  return true;
+}
+
+// Returns TRUE if we should keep processing the event, FALSE if the handler
+// wants to stop the closing of the menu.
+bool nsMenuX::OnClose()
+{
+  if (mDestroyHandlerCalled)
+    return true;
+
+  nsEventStatus status = nsEventStatus_eIgnore;
+  WidgetMouseEvent event(true, eXULPopupHiding, nullptr,
+                         WidgetMouseEvent::eReal);
+
+  nsCOMPtr<nsIContent> popupContent;
+  GetMenuPopupContent(getter_AddRefs(popupContent));
+
+  nsresult rv = NS_OK;
+  nsIContent* dispatchTo = popupContent ? popupContent : mContent;
+  rv = dispatchTo->DispatchDOMEvent(&event, nullptr, nullptr, &status);
+
+  mDestroyHandlerCalled = true;
+
+  if (NS_FAILED(rv) || status == nsEventStatus_eConsumeNoDefault)
+    return false;
+
+  return true;
+}
+
+// Find the |menupopup| child in the |popup| representing this menu. It should be one
+// of a very few children so we won't be iterating over a bazillion menu items to find
+// it (so the strcmp won't kill us).
+void nsMenuX::GetMenuPopupContent(nsIContent** aResult)
+{
+  if (!aResult)
+    return;
+  *aResult = nullptr;
+
+  // Check to see if we are a "menupopup" node (if we are a native menu).
+  {
+    int32_t dummy;
+    nsCOMPtr<nsIAtom> tag = mContent->OwnerDoc()->BindingManager()->ResolveTag(mContent, &dummy);
+    if (tag == nsGkAtoms::menupopup) {
+      *aResult = mContent;
+      NS_ADDREF(*aResult);
+      return;
+    }
+  }
+
+  // Otherwise check our child nodes.
+
+  uint32_t count = mContent->GetChildCount();
+
+  for (uint32_t i = 0; i < count; i++) {
+    int32_t dummy;
+    nsIContent *child = mContent->GetChildAt(i);
+    nsCOMPtr<nsIAtom> tag = child->OwnerDoc()->BindingManager()->ResolveTag(child, &dummy);
+    if (tag == nsGkAtoms::menupopup) {
+      *aResult = child;
+      NS_ADDREF(*aResult);
+      return;
+    }
+  }
+}
+
+NSMenuItem* nsMenuX::NativeMenuItem()
+{
+  return mNativeMenuItem;
+}
+
+bool nsMenuX::IsXULHelpMenu(nsIContent* aMenuContent)
+{
+  bool retval = false;
+  if (aMenuContent) {
+    nsAutoString id;
+    aMenuContent->GetAttr(kNameSpaceID_None, nsGkAtoms::id, id);
+    if (id.Equals(NS_LITERAL_STRING("helpMenu")))
+      retval = true;
+  }
+  return retval;
+}
+
+//
+// nsChangeObserver
+//
+
+void nsMenuX::ObserveAttributeChanged(nsIDocument *aDocument, nsIContent *aContent,
+                                      nsIAtom *aAttribute)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // ignore the |open| attribute, which is by far the most common
+  if (gConstructingMenu || (aAttribute == nsGkAtoms::open))
+    return;
+
+  nsMenuObjectTypeX parentType = mParent->MenuObjectType();
+
+  if (aAttribute == nsGkAtoms::disabled) {
+    SetEnabled(!mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled,
+                                      nsGkAtoms::_true, eCaseMatters));
+  }
+  else if (aAttribute == nsGkAtoms::label) {
+    mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::label, mLabel);
+
+    // invalidate my parent. If we're a submenu parent, we have to rebuild
+    // the parent menu in order for the changes to be picked up. If we're
+    // a regular menu, just change the title and redraw the menubar.
+    if (parentType == eMenuBarObjectType) {
+      // reuse the existing menu, to avoid rebuilding the root menu bar.
+      NS_ASSERTION(mNativeMenu, "nsMenuX::AttributeChanged: invalid menu handle.");
+      NSString *newCocoaLabelString = nsMenuUtilsX::GetTruncatedCocoaLabel(mLabel);
+      [mNativeMenu setTitle:newCocoaLabelString];
+    }
+    else if (parentType == eSubmenuObjectType) {
+      static_cast<nsMenuX*>(mParent)->SetRebuild(true);
+    }
+    else if (parentType == eStandaloneNativeMenuObjectType) {
+      static_cast<nsStandaloneNativeMenu*>(mParent)->GetMenuXObject()->SetRebuild(true);
+    }
+  }
+  else if (aAttribute == nsGkAtoms::hidden || aAttribute == nsGkAtoms::collapsed) {
+    SetRebuild(true);
+
+    bool contentIsHiddenOrCollapsed = nsMenuUtilsX::NodeIsHiddenOrCollapsed(mContent);
+
+    // don't do anything if the state is correct already
+    if (contentIsHiddenOrCollapsed != mVisible)
+      return;
+
+    if (contentIsHiddenOrCollapsed) {
+      if (parentType == eMenuBarObjectType ||
+          parentType == eSubmenuObjectType ||
+          parentType == eStandaloneNativeMenuObjectType) {
+        NSMenu* parentMenu = (NSMenu*)mParent->NativeData();
+        // An exception will get thrown if we try to remove an item that isn't
+        // in the menu.
+        if ([parentMenu indexOfItem:mNativeMenuItem] != -1)
+          [parentMenu removeItem:mNativeMenuItem];
+        mVisible = false;
+      }
+    }
+    else {
+      if (parentType == eMenuBarObjectType ||
+          parentType == eSubmenuObjectType ||
+          parentType == eStandaloneNativeMenuObjectType) {
+        int insertionIndex = nsMenuUtilsX::CalculateNativeInsertionPoint(mParent, this);
+        if (parentType == eMenuBarObjectType) {
+          // Before inserting we need to figure out if we should take the native
+          // application menu into account.
+          nsMenuBarX* mb = static_cast<nsMenuBarX*>(mParent);
+          if (mb->MenuContainsAppMenu())
+            insertionIndex++;
+        }
+        NSMenu* parentMenu = (NSMenu*)mParent->NativeData();
+        [parentMenu insertItem:mNativeMenuItem atIndex:insertionIndex];
+        [mNativeMenuItem setSubmenu:mNativeMenu];
+        mVisible = true;
+      }
+    }
+  }
+  else if (aAttribute == nsGkAtoms::image) {
+    SetupIcon();
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void nsMenuX::ObserveContentRemoved(nsIDocument *aDocument, nsIContent *aChild,
+                                    int32_t aIndexInContainer)
+{
+  if (gConstructingMenu)
+    return;
+
+  SetRebuild(true);
+  mMenuGroupOwner->UnregisterForContentChanges(aChild);
+}
+
+void nsMenuX::ObserveContentInserted(nsIDocument *aDocument, nsIContent* aContainer,
+                                     nsIContent *aChild)
+{
+  if (gConstructingMenu)
+    return;
+
+  SetRebuild(true);
+}
+
+nsresult nsMenuX::SetupIcon()
+{
+  // In addition to out-of-memory, menus that are children of the menu bar
+  // will not have mIcon set.
+  if (!mIcon)
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  return mIcon->SetupIcon();
+}
+
+//
+// MenuDelegate Objective-C class, used to set up Carbon events
+//
+
+@implementation MenuDelegate
+
+- (id)initWithGeckoMenu:(nsMenuX*)geckoMenu
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if ((self = [super init])) {
+    NS_ASSERTION(geckoMenu, "Cannot initialize native menu delegate with NULL gecko menu! Will crash!");
+    mGeckoMenu = geckoMenu;
+  }
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)menu:(NSMenu *)menu willHighlightItem:(NSMenuItem *)item
+{
+  if (!menu || !item || !mGeckoMenu)
+    return;
+
+  nsMenuObjectX* target = mGeckoMenu->GetVisibleItemAt((uint32_t)[menu indexOfItem:item]);
+  if (target && (target->MenuObjectType() == eMenuItemObjectType)) {
+    nsMenuItemX* targetMenuItem = static_cast<nsMenuItemX*>(target);
+    bool handlerCalledPreventDefault; // but we don't actually care
+    targetMenuItem->DispatchDOMEvent(NS_LITERAL_STRING("DOMMenuItemActive"), &handlerCalledPreventDefault);
+  }
+}
+
+- (void)menuWillOpen:(NSMenu *)menu
+{
+  if (!mGeckoMenu)
+    return;
+
+  // Don't do anything while the OS is (re)indexing our menus (on Leopard and
+  // higher).  This stops the Help menu from being able to search in our
+  // menus, but it also resolves many other problems.
+  if (nsMenuX::sIndexingMenuLevel > 0)
+    return;
+
+  nsIRollupListener* rollupListener = nsBaseWidget::GetActiveRollupListener();
+  if (rollupListener) {
+    nsCOMPtr<nsIWidget> rollupWidget = rollupListener->GetRollupWidget();
+    if (rollupWidget) {
+      rollupListener->Rollup(0, true, nullptr, nullptr);
+      [menu cancelTracking];
+      return;
+    }
+  }
+  mGeckoMenu->MenuOpened();
+}
+
+- (void)menuDidClose:(NSMenu *)menu
+{
+  if (!mGeckoMenu)
+    return;
+
+  // Don't do anything while the OS is (re)indexing our menus (on Leopard and
+  // higher).  This stops the Help menu from being able to search in our
+  // menus, but it also resolves many other problems.
+  if (nsMenuX::sIndexingMenuLevel > 0)
+    return;
+
+  mGeckoMenu->MenuClosed();
+}
+
+@end
+
+// OS X Leopard (at least as of 10.5.2) has an obscure bug triggered by some
+// behavior that's present in Mozilla.org browsers but not (as best I can
+// tell) in Apple products like Safari.  (It's not yet clear exactly what this
+// behavior is.)
+//
+// The bug is that sometimes you crash on quit in nsMenuX::RemoveAll(), on a
+// call to [NSMenu removeItemAtIndex:].  The crash is caused by trying to
+// access a deleted NSMenuItem object (sometimes (perhaps always?) by trying
+// to send it a _setChangedFlags: message).  Though this object was deleted
+// some time ago, it remains registered as a potential target for a particular
+// key equivalent.  So when [NSMenu removeItemAtIndex:] removes the current
+// target for that same key equivalent, the OS tries to "activate" the
+// previous target.
+//
+// The underlying reason appears to be that NSMenu's _addItem:toTable: and
+// _removeItem:fromTable: methods (which are used to keep a hashtable of
+// registered key equivalents) don't properly "retain" and "release"
+// NSMenuItem objects as they are added to and removed from the hashtable.
+//
+// Our (hackish) workaround is to shadow the OS's hashtable with another
+// hastable of our own (gShadowKeyEquivDB), and use it to "retain" and
+// "release" NSMenuItem objects as needed.  This resolves bmo bugs 422287 and
+// 423669.  When (if) Apple fixes this bug, we can remove this workaround.
+
+static NSMutableDictionary *gShadowKeyEquivDB = nil;
+
+// Class for values in gShadowKeyEquivDB.
+
+@interface KeyEquivDBItem : NSObject
+{
+  NSMenuItem *mItem;
+  NSMutableSet *mTables;
+}
+
+- (id)initWithItem:(NSMenuItem *)aItem table:(NSMapTable *)aTable;
+- (BOOL)hasTable:(NSMapTable *)aTable;
+- (int)addTable:(NSMapTable *)aTable;
+- (int)removeTable:(NSMapTable *)aTable;
+
+@end
+
+@implementation KeyEquivDBItem
+
+- (id)initWithItem:(NSMenuItem *)aItem table:(NSMapTable *)aTable
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if (!gShadowKeyEquivDB)
+    gShadowKeyEquivDB = [[NSMutableDictionary alloc] init];
+  self = [super init];
+  if (aItem && aTable) {
+    mTables = [[NSMutableSet alloc] init];
+    mItem = [aItem retain];
+    [mTables addObject:[NSValue valueWithPointer:aTable]];
+  } else {
+    mTables = nil;
+    mItem = nil;
+  }
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mTables)
+    [mTables release];
+  if (mItem)
+    [mItem release];
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (BOOL)hasTable:(NSMapTable *)aTable
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  return [mTables member:[NSValue valueWithPointer:aTable]] ? YES : NO;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NO);
+}
+
+// Does nothing if aTable (its index value) is already present in mTables.
+- (int)addTable:(NSMapTable *)aTable
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (aTable)
+    [mTables addObject:[NSValue valueWithPointer:aTable]];
+  return [mTables count];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0);
+}
+
+- (int)removeTable:(NSMapTable *)aTable
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (aTable) {
+    NSValue *objectToRemove =
+      [mTables member:[NSValue valueWithPointer:aTable]];
+    if (objectToRemove)
+      [mTables removeObject:objectToRemove];
+  }
+  return [mTables count];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(0);
+}
+
+@end
+
+@interface NSMenu (MethodSwizzling)
++ (void)nsMenuX_NSMenu_addItem:(NSMenuItem *)aItem toTable:(NSMapTable *)aTable;
++ (void)nsMenuX_NSMenu_removeItem:(NSMenuItem *)aItem fromTable:(NSMapTable *)aTable;
+@end
+
+@implementation NSMenu (MethodSwizzling)
+
++ (void)nsMenuX_NSMenu_addItem:(NSMenuItem *)aItem toTable:(NSMapTable *)aTable
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (aItem && aTable) {
+    NSValue *key = [NSValue valueWithPointer:aItem];
+    KeyEquivDBItem *shadowItem = [gShadowKeyEquivDB objectForKey:key];
+    if (shadowItem) {
+      [shadowItem addTable:aTable];
+    } else {
+      shadowItem = [[KeyEquivDBItem alloc] initWithItem:aItem table:aTable];
+      [gShadowKeyEquivDB setObject:shadowItem forKey:key];
+      // Release after [NSMutableDictionary setObject:forKey:] retains it (so
+      // that it will get dealloced when removeObjectForKey: is called).
+      [shadowItem release];
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+
+  [self nsMenuX_NSMenu_addItem:aItem toTable:aTable];
+}
+
++ (void)nsMenuX_NSMenu_removeItem:(NSMenuItem *)aItem fromTable:(NSMapTable *)aTable
+{
+  [self nsMenuX_NSMenu_removeItem:aItem fromTable:aTable];
+
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (aItem && aTable) {
+    NSValue *key = [NSValue valueWithPointer:aItem];
+    KeyEquivDBItem *shadowItem = [gShadowKeyEquivDB objectForKey:key];
+    if (shadowItem && [shadowItem hasTable:aTable]) {
+      if (![shadowItem removeTable:aTable])
+        [gShadowKeyEquivDB removeObjectForKey:key];
+    }
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@end
+
+// This class is needed to keep track of when the OS is (re)indexing all of
+// our menus.  This appears to only happen on Leopard and higher, and can
+// be triggered by opening the Help menu.  Some operations are unsafe while
+// this is happening -- notably the calls to [[NSImage alloc]
+// initWithSize:imageRect.size] and [newImage lockFocus] in nsMenuItemIconX::
+// OnStopFrame().  But we don't yet have a complete list, and Apple doesn't
+// yet have any documentation on this subject.  (Apple also doesn't yet have
+// any documented way to find the information we seek here.)  The "original"
+// of this class (the one whose indexMenuBarDynamically method we hook) is
+// defined in the Shortcut framework in /System/Library/PrivateFrameworks.
+@interface NSObject (SCTGRLIndexMethodSwizzling)
+- (void)nsMenuX_SCTGRLIndex_indexMenuBarDynamically;
+@end
+
+@implementation NSObject (SCTGRLIndexMethodSwizzling)
+
+- (void)nsMenuX_SCTGRLIndex_indexMenuBarDynamically
+{
+  // This method appears to be called (once) whenever the OS (re)indexes our
+  // menus.  sIndexingMenuLevel is a int32_t just in case it might be
+  // reentered.  As it's running, it spawns calls to two undocumented
+  // HIToolbox methods (_SimulateMenuOpening() and _SimulateMenuClosed()),
+  // which "simulate" the opening and closing of our menus without actually
+  // displaying them.
+  ++nsMenuX::sIndexingMenuLevel;
+  [self nsMenuX_SCTGRLIndex_indexMenuBarDynamically];
+  --nsMenuX::sIndexingMenuLevel;
+}
+
+@end
diff --git a/widget/cocoa/nsNativeThemeCocoa.h b/widget/cocoa/nsNativeThemeCocoa.h
new file mode 100644
index 0000000000..23f2bc4d32
--- /dev/null
+++ b/widget/cocoa/nsNativeThemeCocoa.h
@@ -0,0 +1,178 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsNativeThemeCocoa_h_
+#define nsNativeThemeCocoa_h_
+
+#import <Carbon/Carbon.h>
+#import <Cocoa/Cocoa.h>
+
+#include "nsITheme.h"
+#include "nsCOMPtr.h"
+#include "nsIAtom.h"
+#include "nsNativeTheme.h"
+
+@class CellDrawView;
+@class NSProgressBarCell;
+@class ContextAwareSearchFieldCell;
+class nsDeviceContext;
+struct SegmentedControlRenderSettings;
+
+namespace mozilla {
+class EventStates;
+} // namespace mozilla
+
+class nsNativeThemeCocoa : private nsNativeTheme,
+                           public nsITheme
+{
+public:
+  enum {
+    eThemeGeometryTypeTitlebar = eThemeGeometryTypeUnknown + 1,
+    eThemeGeometryTypeToolbar,
+    eThemeGeometryTypeToolbox,
+    eThemeGeometryTypeWindowButtons,
+    eThemeGeometryTypeFullscreenButton,
+    eThemeGeometryTypeMenu,
+    eThemeGeometryTypeHighlightedMenuItem,
+    eThemeGeometryTypeVibrancyLight,
+    eThemeGeometryTypeVibrancyDark,
+    eThemeGeometryTypeTooltip,
+    eThemeGeometryTypeSheet,
+    eThemeGeometryTypeSourceList,
+    eThemeGeometryTypeSourceListSelection,
+    eThemeGeometryTypeActiveSourceListSelection
+  };
+
+  nsNativeThemeCocoa();
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+  // The nsITheme interface.
+  NS_IMETHOD DrawWidgetBackground(nsRenderingContext* aContext,
+                                  nsIFrame* aFrame,
+                                  uint8_t aWidgetType,
+                                  const nsRect& aRect,
+                                  const nsRect& aDirtyRect) override;
+  NS_IMETHOD GetWidgetBorder(nsDeviceContext* aContext, 
+                             nsIFrame* aFrame,
+                             uint8_t aWidgetType,
+                             nsIntMargin* aResult) override;
+
+  virtual bool GetWidgetPadding(nsDeviceContext* aContext,
+                                  nsIFrame* aFrame,
+                                  uint8_t aWidgetType,
+                                  nsIntMargin* aResult) override;
+
+  virtual bool GetWidgetOverflow(nsDeviceContext* aContext, nsIFrame* aFrame,
+                                   uint8_t aWidgetType, nsRect* aOverflowRect) override;
+
+  NS_IMETHOD GetMinimumWidgetSize(nsPresContext* aPresContext, nsIFrame* aFrame,
+                                  uint8_t aWidgetType,
+                                  mozilla::LayoutDeviceIntSize* aResult, bool* aIsOverridable) override;
+  NS_IMETHOD WidgetStateChanged(nsIFrame* aFrame, uint8_t aWidgetType, 
+                                nsIAtom* aAttribute, bool* aShouldRepaint,
+                                const nsAttrValue* aOldValue) override;
+  NS_IMETHOD ThemeChanged() override;
+  bool ThemeSupportsWidget(nsPresContext* aPresContext, nsIFrame* aFrame, uint8_t aWidgetType) override;
+  bool WidgetIsContainer(uint8_t aWidgetType) override;
+  bool ThemeDrawsFocusForWidget(uint8_t aWidgetType) override;
+  bool ThemeNeedsComboboxDropmarker() override;
+  virtual bool WidgetAppearanceDependsOnWindowFocus(uint8_t aWidgetType) override;
+  virtual bool NeedToClearBackgroundBehindWidget(nsIFrame* aFrame,
+                                                 uint8_t aWidgetType) override;
+  virtual bool WidgetProvidesFontSmoothingBackgroundColor(nsIFrame* aFrame, uint8_t aWidgetType,
+                                                          nscolor* aColor) override;
+  virtual ThemeGeometryType ThemeGeometryTypeForWidget(nsIFrame* aFrame,
+                                                       uint8_t aWidgetType) override;
+  virtual Transparency GetWidgetTransparency(nsIFrame* aFrame, uint8_t aWidgetType) override;
+
+  void DrawProgress(CGContextRef context, const HIRect& inBoxRect,
+                    bool inIsIndeterminate, bool inIsHorizontal,
+                    double inValue, double inMaxValue, nsIFrame* aFrame);
+
+  static void DrawNativeTitlebar(CGContextRef aContext, CGRect aTitlebarRect,
+                                 CGFloat aUnifiedHeight, BOOL aIsMain, BOOL aIsFlipped);
+
+protected:
+  virtual ~nsNativeThemeCocoa();
+
+  nsIntMargin DirectionAwareMargin(const nsIntMargin& aMargin, nsIFrame* aFrame);
+  nsIFrame* SeparatorResponsibility(nsIFrame* aBefore, nsIFrame* aAfter);
+  CGRect SeparatorAdjustedRect(CGRect aRect, nsIFrame* aLeft,
+                               nsIFrame* aCurrent, nsIFrame* aRight);
+  bool IsWindowSheet(nsIFrame* aFrame);
+
+  // HITheme drawing routines
+  void DrawFrame(CGContextRef context, HIThemeFrameKind inKind,
+                 const HIRect& inBoxRect, bool inReadOnly,
+                 mozilla::EventStates inState);
+  void DrawMeter(CGContextRef context, const HIRect& inBoxRect,
+                 nsIFrame* aFrame);
+  void DrawSegment(CGContextRef cgContext, const HIRect& inBoxRect,
+                   mozilla::EventStates inState, nsIFrame* aFrame,
+                   const SegmentedControlRenderSettings& aSettings);
+  void DrawTabPanel(CGContextRef context, const HIRect& inBoxRect, nsIFrame* aFrame);
+  void DrawScale(CGContextRef context, const HIRect& inBoxRect,
+                 mozilla::EventStates inState, bool inDirection,
+                 bool inIsReverse, int32_t inCurrentValue, int32_t inMinValue,
+                 int32_t inMaxValue, nsIFrame* aFrame);
+  void DrawCheckboxOrRadio(CGContextRef cgContext, bool inCheckbox,
+                           const HIRect& inBoxRect, bool inSelected,
+                           mozilla::EventStates inState, nsIFrame* aFrame);
+  void DrawSearchField(CGContextRef cgContext, const HIRect& inBoxRect,
+                       nsIFrame* aFrame, mozilla::EventStates inState);
+  void DrawPushButton(CGContextRef cgContext, const HIRect& inBoxRect,
+                      mozilla::EventStates inState, uint8_t aWidgetType,
+                      nsIFrame* aFrame, float aOriginalHeight);
+  void DrawMenuIcon(CGContextRef cgContext, const CGRect& aRect,
+                    mozilla::EventStates inState, nsIFrame* aFrame,
+                    const NSSize& aIconSize, NSString* aImageName,
+                    bool aCenterHorizontally);
+  void DrawButton(CGContextRef context, ThemeButtonKind inKind,
+                  const HIRect& inBoxRect, bool inIsDefault, 
+                  ThemeButtonValue inValue, ThemeButtonAdornment inAdornment,
+                  mozilla::EventStates inState, nsIFrame* aFrame);
+  void DrawFocusOutline(CGContextRef cgContext, const HIRect& inBoxRect,
+                        mozilla::EventStates inState, uint8_t aWidgetType,
+                        nsIFrame* aFrame);
+  void DrawDropdown(CGContextRef context, const HIRect& inBoxRect,
+                    mozilla::EventStates inState, uint8_t aWidgetType,
+                    nsIFrame* aFrame);
+  void DrawSpinButtons(CGContextRef context, ThemeButtonKind inKind,
+                       const HIRect& inBoxRect, ThemeDrawState inDrawState,
+                       ThemeButtonAdornment inAdornment,
+                       mozilla::EventStates inState, nsIFrame* aFrame);
+  void DrawSpinButton(CGContextRef context, ThemeButtonKind inKind,
+                      const HIRect& inBoxRect, ThemeDrawState inDrawState,
+                      ThemeButtonAdornment inAdornment,
+                      mozilla::EventStates inState,
+                      nsIFrame* aFrame, uint8_t aWidgetType);
+  void DrawUnifiedToolbar(CGContextRef cgContext, const HIRect& inBoxRect,
+                          NSWindow* aWindow);
+  void DrawStatusBar(CGContextRef cgContext, const HIRect& inBoxRect,
+                     nsIFrame *aFrame);
+  void DrawResizer(CGContextRef cgContext, const HIRect& aRect, nsIFrame *aFrame);
+
+  // Scrollbars
+  void GetScrollbarPressStates(nsIFrame *aFrame,
+                               mozilla::EventStates aButtonStates[]);
+  nsIFrame* GetParentScrollbarFrame(nsIFrame *aFrame);
+  bool IsParentScrollbarRolledOver(nsIFrame* aFrame);
+
+private:
+  NSButtonCell* mDisclosureButtonCell;
+  NSButtonCell* mHelpButtonCell;
+  NSButtonCell* mPushButtonCell;
+  NSButtonCell* mRadioButtonCell;
+  NSButtonCell* mCheckboxCell;
+  ContextAwareSearchFieldCell* mSearchFieldCell;
+  NSPopUpButtonCell* mDropdownCell;
+  NSComboBoxCell* mComboBoxCell;
+  NSProgressBarCell* mProgressBarCell;
+  NSLevelIndicatorCell* mMeterBarCell;
+  CellDrawView* mCellDrawView;
+};
+
+#endif // nsNativeThemeCocoa_h_
diff --git a/widget/cocoa/nsNativeThemeCocoa.mm b/widget/cocoa/nsNativeThemeCocoa.mm
new file mode 100644
index 0000000000..056c453f2a
--- /dev/null
+++ b/widget/cocoa/nsNativeThemeCocoa.mm
@@ -0,0 +1,3961 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsNativeThemeCocoa.h"
+
+#include "mozilla/gfx/2D.h"
+#include "mozilla/gfx/Helpers.h"
+#include "nsChildView.h"
+#include "nsDeviceContext.h"
+#include "nsLayoutUtils.h"
+#include "nsObjCExceptions.h"
+#include "nsNumberControlFrame.h"
+#include "nsRangeFrame.h"
+#include "nsRenderingContext.h"
+#include "nsRect.h"
+#include "nsSize.h"
+#include "nsThemeConstants.h"
+#include "nsIPresShell.h"
+#include "nsPresContext.h"
+#include "nsIContent.h"
+#include "nsIDocument.h"
+#include "nsIFrame.h"
+#include "nsIAtom.h"
+#include "nsNameSpaceManager.h"
+#include "nsPresContext.h"
+#include "nsGkAtoms.h"
+#include "nsCocoaFeatures.h"
+#include "nsCocoaWindow.h"
+#include "nsNativeThemeColors.h"
+#include "nsIScrollableFrame.h"
+#include "mozilla/EventStates.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/HTMLMeterElement.h"
+#include "nsLookAndFeel.h"
+#include "VibrancyManager.h"
+
+#include "gfxContext.h"
+#include "gfxQuartzSurface.h"
+#include "gfxQuartzNativeDrawing.h"
+#include <algorithm>
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+using mozilla::dom::HTMLMeterElement;
+
+#define DRAW_IN_FRAME_DEBUG 0
+#define SCROLLBARS_VISUAL_DEBUG 0
+
+// private Quartz routines needed here
+extern "C" {
+  CG_EXTERN void CGContextSetCTM(CGContextRef, CGAffineTransform);
+  CG_EXTERN void CGContextSetBaseCTM(CGContextRef, CGAffineTransform);
+  typedef CFTypeRef CUIRendererRef;
+  void CUIDraw(CUIRendererRef r, CGRect rect, CGContextRef ctx, CFDictionaryRef options, CFDictionaryRef* result);
+}
+
+// Workaround for NSCell control tint drawing
+// Without this workaround, NSCells are always drawn with the clear control tint
+// as long as they're not attached to an NSControl which is a subview of an active window.
+// XXXmstange Why doesn't Webkit need this?
+@implementation NSCell (ControlTintWorkaround)
+- (int)_realControlTint { return [self controlTint]; }
+@end
+
+// The purpose of this class is to provide objects that can be used when drawing
+// NSCells using drawWithFrame:inView: without causing any harm. The only
+// messages that will be sent to such an object are "isFlipped" and
+// "currentEditor": isFlipped needs to return YES in order to avoid drawing bugs
+// on 10.4 (see bug 465069); currentEditor (which isn't even a method of
+// NSView) will be called when drawing search fields, and we only provide it in
+// order to prevent "unrecognized selector" exceptions.
+// There's no need to pass the actual NSView that we're drawing into to
+// drawWithFrame:inView:. What's more, doing so even causes unnecessary
+// invalidations as soon as we draw a focusring!
+@interface CellDrawView : NSView
+
+@end;
+
+@implementation CellDrawView
+
+- (BOOL)isFlipped
+{
+  return YES;
+}
+
+- (NSText*)currentEditor
+{
+  return nil;
+}
+
+@end
+
+// These two classes don't actually add any behavior over NSButtonCell. Their
+// purpose is to make it easy to distinguish NSCell objects that are used for
+// drawing radio buttons / checkboxes from other cell types.
+// The class names are made up, there are no classes with these names in AppKit.
+// The reason we need them is that calling [cell setButtonType:NSRadioButton]
+// doesn't leave an easy-to-check "marker" on the cell object - there is no
+// -[NSButtonCell buttonType] method.
+@interface RadioButtonCell : NSButtonCell
+@end;
+@implementation RadioButtonCell @end;
+@interface CheckboxCell : NSButtonCell
+@end;
+@implementation CheckboxCell @end;
+
+static void
+DrawFocusRingForCellIfNeeded(NSCell* aCell, NSRect aWithFrame, NSView* aInView)
+{
+  if ([aCell showsFirstResponder]) {
+    CGContextRef cgContext = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
+    CGContextSaveGState(cgContext);
+
+    // It's important to set the focus ring style before we enter the
+    // transparency layer so that the transparency layer only contains
+    // the normal button mask without the focus ring, and the conversion
+    // to the focus ring shape happens only when the transparency layer is
+    // ended.
+    NSSetFocusRingStyle(NSFocusRingOnly);
+
+    // We need to draw the whole button into a transparency layer because
+    // many button types are composed of multiple parts, and if these parts
+    // were drawn while the focus ring style was active, each individual part
+    // would produce a focus ring for itself. But we only want one focus ring
+    // for the whole button. The transparency layer is a way to merge the
+    // individual button parts together before the focus ring shape is
+    // calculated.
+    CGContextBeginTransparencyLayerWithRect(cgContext, NSRectToCGRect(aWithFrame), 0);
+    [aCell drawFocusRingMaskWithFrame:aWithFrame inView:aInView];
+    CGContextEndTransparencyLayer(cgContext);
+
+    CGContextRestoreGState(cgContext);
+  }
+}
+
+static bool
+FocusIsDrawnByDrawWithFrame(NSCell* aCell)
+{
+#if defined(MAC_OS_X_VERSION_10_8) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
+  // When building with the 10.8 SDK or higher, focus rings don't draw as part
+  // of -[NSCell drawWithFrame:inView:] and must be drawn by a separate call
+  // to -[NSCell drawFocusRingMaskWithFrame:inView:]; .
+  // See the NSButtonCell section under
+  // https://developer.apple.com/library/mac/releasenotes/AppKit/RN-AppKitOlderNotes/#X10_8Notes
+  return false;
+#else
+  if (!nsCocoaFeatures::OnYosemiteOrLater()) {
+    // When building with the 10.7 SDK or lower, focus rings always draw as
+    // part of -[NSCell drawWithFrame:inView:] if the build is run on 10.9 or
+    // lower.
+    return true;
+  }
+
+  // On 10.10, whether the focus ring is drawn as part of
+  // -[NSCell drawWithFrame:inView:] depends on the cell type.
+  // Radio buttons and checkboxes draw their own focus rings, other cell
+  // types need -[NSCell drawFocusRingMaskWithFrame:inView:].
+  return [aCell isKindOfClass:[RadioButtonCell class]] ||
+         [aCell isKindOfClass:[CheckboxCell class]];
+#endif
+}
+
+static void
+DrawCellIncludingFocusRing(NSCell* aCell, NSRect aWithFrame, NSView* aInView)
+{
+  [aCell drawWithFrame:aWithFrame inView:aInView];
+
+  if (!FocusIsDrawnByDrawWithFrame(aCell)) {
+    DrawFocusRingForCellIfNeeded(aCell, aWithFrame, aInView);
+  }
+}
+
+/**
+ * NSProgressBarCell is used to draw progress bars of any size.
+ */
+@interface NSProgressBarCell : NSCell
+{
+    /*All instance variables are private*/
+    double mValue;
+    double mMax;
+    bool   mIsIndeterminate;
+    bool   mIsHorizontal;
+}
+
+- (void)setValue:(double)value;
+- (double)value;
+- (void)setMax:(double)max;
+- (double)max;
+- (void)setIndeterminate:(bool)aIndeterminate;
+- (bool)isIndeterminate;
+- (void)setHorizontal:(bool)aIsHorizontal;
+- (bool)isHorizontal;
+- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView;
+@end
+
+@implementation NSProgressBarCell
+
+- (void)setMax:(double)aMax
+{
+  mMax = aMax;
+}
+
+- (double)max
+{
+  return mMax;
+}
+
+- (void)setValue:(double)aValue
+{
+  mValue = aValue;
+}
+
+- (double)value
+{
+  return mValue;
+}
+
+- (void)setIndeterminate:(bool)aIndeterminate
+{
+  mIsIndeterminate = aIndeterminate;
+}
+
+- (bool)isIndeterminate
+{
+  return mIsIndeterminate;
+}
+
+- (void)setHorizontal:(bool)aIsHorizontal
+{
+  mIsHorizontal = aIsHorizontal;
+}
+
+- (bool)isHorizontal
+{
+  return mIsHorizontal;
+}
+
+- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView
+{
+  CGContext* cgContext = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
+
+  HIThemeTrackDrawInfo tdi;
+
+  tdi.version = 0;
+  tdi.min = 0;
+
+  tdi.value = INT32_MAX * (mValue / mMax);
+  tdi.max = INT32_MAX;
+  tdi.bounds = NSRectToCGRect(cellFrame);
+  tdi.attributes = mIsHorizontal ? kThemeTrackHorizontal : 0;
+  tdi.enableState = [self controlTint] == NSClearControlTint ? kThemeTrackInactive
+                                                             : kThemeTrackActive;
+
+  NSControlSize size = [self controlSize];
+  if (size == NSRegularControlSize) {
+    tdi.kind = mIsIndeterminate ? kThemeLargeIndeterminateBar
+                                : kThemeLargeProgressBar;
+  } else {
+    NS_ASSERTION(size == NSSmallControlSize,
+                 "We shouldn't have another size than small and regular for the moment");
+    tdi.kind = mIsIndeterminate ? kThemeMediumIndeterminateBar
+                                : kThemeMediumProgressBar;
+  }
+
+  int32_t stepsPerSecond = mIsIndeterminate ? 60 : 30;
+  int32_t milliSecondsPerStep = 1000 / stepsPerSecond;
+  tdi.trackInfo.progress.phase = uint8_t(PR_IntervalToMilliseconds(PR_IntervalNow()) /
+                                         milliSecondsPerStep);
+
+  HIThemeDrawTrack(&tdi, NULL, cgContext, kHIThemeOrientationNormal);
+}
+
+@end
+
+@interface ContextAwareSearchFieldCell : NSSearchFieldCell
+{
+  nsIFrame* mContext;
+}
+
+// setContext: stores the searchfield nsIFrame so that it can be consulted
+// during painting. Please reset this by calling setContext:nullptr as soon as
+// you're done with painting because we don't want to keep a dangling pointer.
+- (void)setContext:(nsIFrame*)aContext;
+@end
+
+@implementation ContextAwareSearchFieldCell
+
+- (id)initTextCell:(NSString*)aString
+{
+  if ((self = [super initTextCell:aString])) {
+    mContext = nullptr;
+  }
+  return self;
+}
+
+- (void)setContext:(nsIFrame*)aContext
+{
+  mContext = aContext;
+}
+
+static BOOL IsToolbarStyleContainer(nsIFrame* aFrame)
+{
+  nsIContent* content = aFrame->GetContent();
+  if (!content)
+    return NO;
+
+  if (content->IsAnyOfXULElements(nsGkAtoms::toolbar,
+                                  nsGkAtoms::toolbox,
+                                  nsGkAtoms::statusbar))
+    return YES;
+
+  switch (aFrame->StyleDisplay()->mAppearance) {
+    case NS_THEME_TOOLBAR:
+    case NS_THEME_STATUSBAR:
+      return YES;
+    default:
+      return NO;
+  }
+}
+
+- (BOOL)_isToolbarMode
+{
+  // On 10.7, searchfields have two different styles, depending on whether
+  // the searchfield is on top of of window chrome. This function is called on
+  // 10.7 during drawing in order to determine which style to use.
+  for (nsIFrame* frame = mContext; frame; frame = frame->GetParent()) {
+    if (IsToolbarStyleContainer(frame)) {
+      return YES;
+    }
+  }
+  return NO;
+}
+
+@end
+
+// Workaround for Bug 542048
+// On 64-bit, NSSearchFieldCells don't draw focus rings.
+#if defined(__x86_64__)
+
+@interface SearchFieldCellWithFocusRing : ContextAwareSearchFieldCell {} @end
+
+@implementation SearchFieldCellWithFocusRing
+
+- (void)drawWithFrame:(NSRect)rect inView:(NSView*)controlView
+{
+  [super drawWithFrame:rect inView:controlView];
+
+  if (FocusIsDrawnByDrawWithFrame(self)) {
+    // For some reason, -[NSSearchFieldCell drawWithFrame:inView] doesn't draw a
+    // focus ring in 64 bit mode, no matter what SDK is used or what OS X version
+    // we're running on. But if FocusIsDrawnByDrawWithFrame(self), then our
+    // caller expects us to draw a focus ring. So we just do that here.
+    DrawFocusRingForCellIfNeeded(self, rect, controlView);
+  }
+}
+
+- (void)drawFocusRingMaskWithFrame:(NSRect)rect inView:(NSView*)controlView
+{
+  // By default this draws nothing. I don't know why.
+  // We just draw the search field again. It's a great mask shape for its own
+  // focus ring.
+  [super drawWithFrame:rect inView:controlView];
+}
+
+@end
+
+#endif
+
+#define HITHEME_ORIENTATION kHIThemeOrientationNormal
+
+static CGFloat kMaxFocusRingWidth = 0; // initialized by the nsNativeThemeCocoa constructor
+
+// These enums are for indexing into the margin array.
+enum {
+  leopardOSorlater = 0, // 10.6 - 10.9
+  yosemiteOSorlater = 1 // 10.10+
+};
+
+enum {
+  miniControlSize,
+  smallControlSize,
+  regularControlSize
+};
+
+enum {
+  leftMargin,
+  topMargin,
+  rightMargin,
+  bottomMargin
+};
+
+static size_t EnumSizeForCocoaSize(NSControlSize cocoaControlSize) {
+  if (cocoaControlSize == NSMiniControlSize)
+    return miniControlSize;
+  else if (cocoaControlSize == NSSmallControlSize)
+    return smallControlSize;
+  else
+    return regularControlSize;
+}
+
+static NSControlSize CocoaSizeForEnum(int32_t enumControlSize) {
+  if (enumControlSize == miniControlSize)
+    return NSMiniControlSize;
+  else if (enumControlSize == smallControlSize)
+    return NSSmallControlSize;
+  else
+    return NSRegularControlSize;
+}
+
+static NSString* CUIControlSizeForCocoaSize(NSControlSize aControlSize)
+{
+  if (aControlSize == NSRegularControlSize)
+    return @"regular";
+  else if (aControlSize == NSSmallControlSize)
+    return @"small";
+  else
+    return @"mini";
+}
+
+static void InflateControlRect(NSRect* rect, NSControlSize cocoaControlSize, const float marginSet[][3][4])
+{
+  if (!marginSet)
+    return;
+
+  static int osIndex = nsCocoaFeatures::OnYosemiteOrLater() ?
+                         yosemiteOSorlater : leopardOSorlater;
+  size_t controlSize = EnumSizeForCocoaSize(cocoaControlSize);
+  const float* buttonMargins = marginSet[osIndex][controlSize];
+  rect->origin.x -= buttonMargins[leftMargin];
+  rect->origin.y -= buttonMargins[bottomMargin];
+  rect->size.width += buttonMargins[leftMargin] + buttonMargins[rightMargin];
+  rect->size.height += buttonMargins[bottomMargin] + buttonMargins[topMargin];
+}
+
+static ChildView* ChildViewForFrame(nsIFrame* aFrame)
+{
+  if (!aFrame)
+    return nil;
+
+  nsIWidget* widget = aFrame->GetNearestWidget();
+  if (!widget)
+    return nil;
+
+  NSWindow* window = (NSWindow*)widget->GetNativeData(NS_NATIVE_WINDOW);
+  return [window isKindOfClass:[BaseWindow class]] ? [(BaseWindow*)window mainChildView]  : nil;
+}
+
+static NSWindow* NativeWindowForFrame(nsIFrame* aFrame,
+                                      nsIWidget** aTopLevelWidget = NULL)
+{
+  if (!aFrame)
+    return nil;  
+
+  nsIWidget* widget = aFrame->GetNearestWidget();
+  if (!widget)
+    return nil;
+
+  nsIWidget* topLevelWidget = widget->GetTopLevelWidget();
+  if (aTopLevelWidget)
+    *aTopLevelWidget = topLevelWidget;
+
+  return (NSWindow*)topLevelWidget->GetNativeData(NS_NATIVE_WINDOW);
+}
+
+static NSSize
+WindowButtonsSize(nsIFrame* aFrame)
+{
+  NSWindow* window = NativeWindowForFrame(aFrame);
+  if (!window) {
+    // Return fallback values.
+    return NSMakeSize(54, 16);
+  }
+
+  NSRect buttonBox = NSZeroRect;
+  NSButton* closeButton = [window standardWindowButton:NSWindowCloseButton];
+  if (closeButton) {
+    buttonBox = NSUnionRect(buttonBox, [closeButton frame]);
+  }
+  NSButton* minimizeButton = [window standardWindowButton:NSWindowMiniaturizeButton];
+  if (minimizeButton) {
+    buttonBox = NSUnionRect(buttonBox, [minimizeButton frame]);
+  }
+  NSButton* zoomButton = [window standardWindowButton:NSWindowZoomButton];
+  if (zoomButton) {
+    buttonBox = NSUnionRect(buttonBox, [zoomButton frame]);
+  }
+  return buttonBox.size;
+}
+
+static BOOL FrameIsInActiveWindow(nsIFrame* aFrame)
+{
+  nsIWidget* topLevelWidget = NULL;
+  NSWindow* win = NativeWindowForFrame(aFrame, &topLevelWidget);
+  if (!topLevelWidget || !win)
+    return YES;
+
+  // XUL popups, e.g. the toolbar customization popup, can't become key windows,
+  // but controls in these windows should still get the active look.
+  if (topLevelWidget->WindowType() == eWindowType_popup)
+    return YES;
+  if ([win isSheet])
+    return [win isKeyWindow];
+  return [win isMainWindow] && ![win attachedSheet];
+}
+
+// Toolbar controls and content controls respond to different window
+// activeness states.
+static BOOL IsActive(nsIFrame* aFrame, BOOL aIsToolbarControl)
+{
+  if (aIsToolbarControl)
+    return [NativeWindowForFrame(aFrame) isMainWindow];
+  return FrameIsInActiveWindow(aFrame);
+}
+
+static bool IsInSourceList(nsIFrame* aFrame) {
+  for (nsIFrame* frame = aFrame->GetParent(); frame; frame = frame->GetParent()) {
+    if (frame->StyleDisplay()->mAppearance == NS_THEME_MAC_SOURCE_LIST) {
+      return true;
+    }
+  }
+  return false;
+}
+
+NS_IMPL_ISUPPORTS_INHERITED(nsNativeThemeCocoa, nsNativeTheme, nsITheme)
+
+nsNativeThemeCocoa::nsNativeThemeCocoa()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  kMaxFocusRingWidth = nsCocoaFeatures::OnYosemiteOrLater() ? 7 : 4;
+
+  // provide a local autorelease pool, as this is called during startup
+  // before the main event-loop pool is in place
+  nsAutoreleasePool pool;
+
+  mDisclosureButtonCell = [[NSButtonCell alloc] initTextCell:@""];
+  [mDisclosureButtonCell setBezelStyle:NSRoundedDisclosureBezelStyle];
+  [mDisclosureButtonCell setButtonType:NSPushOnPushOffButton];
+  [mDisclosureButtonCell setHighlightsBy:NSPushInCellMask];
+  
+  mHelpButtonCell = [[NSButtonCell alloc] initTextCell:@""];
+  [mHelpButtonCell setBezelStyle:NSHelpButtonBezelStyle];
+  [mHelpButtonCell setButtonType:NSMomentaryPushInButton];
+  [mHelpButtonCell setHighlightsBy:NSPushInCellMask];
+
+  mPushButtonCell = [[NSButtonCell alloc] initTextCell:@""];
+  [mPushButtonCell setButtonType:NSMomentaryPushInButton];
+  [mPushButtonCell setHighlightsBy:NSPushInCellMask];
+
+  mRadioButtonCell = [[RadioButtonCell alloc] initTextCell:@""];
+  [mRadioButtonCell setButtonType:NSRadioButton];
+
+  mCheckboxCell = [[CheckboxCell alloc] initTextCell:@""];
+  [mCheckboxCell setButtonType:NSSwitchButton];
+  [mCheckboxCell setAllowsMixedState:YES];
+
+#if defined(__x86_64__)
+  mSearchFieldCell = [[SearchFieldCellWithFocusRing alloc] initTextCell:@""];
+#else
+  mSearchFieldCell = [[ContextAwareSearchFieldCell alloc] initTextCell:@""];
+#endif
+  [mSearchFieldCell setBezelStyle:NSTextFieldRoundedBezel];
+  [mSearchFieldCell setBezeled:YES];
+  [mSearchFieldCell setEditable:YES];
+  [mSearchFieldCell setFocusRingType:NSFocusRingTypeExterior];
+
+  mDropdownCell = [[NSPopUpButtonCell alloc] initTextCell:@"" pullsDown:NO];
+
+  mComboBoxCell = [[NSComboBoxCell alloc] initTextCell:@""];
+  [mComboBoxCell setBezeled:YES];
+  [mComboBoxCell setEditable:YES];
+  [mComboBoxCell setFocusRingType:NSFocusRingTypeExterior];
+
+  mProgressBarCell = [[NSProgressBarCell alloc] init];
+
+  mMeterBarCell = [[NSLevelIndicatorCell alloc]
+                    initWithLevelIndicatorStyle:NSContinuousCapacityLevelIndicatorStyle];
+
+  mCellDrawView = [[CellDrawView alloc] init];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsNativeThemeCocoa::~nsNativeThemeCocoa()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mMeterBarCell release];
+  [mProgressBarCell release];
+  [mDisclosureButtonCell release];
+  [mHelpButtonCell release];
+  [mPushButtonCell release];
+  [mRadioButtonCell release];
+  [mCheckboxCell release];
+  [mSearchFieldCell release];
+  [mDropdownCell release];
+  [mComboBoxCell release];
+  [mCellDrawView release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Limit on the area of the target rect (in pixels^2) in
+// DrawCellWithScaling() and DrawButton() and above which we
+// don't draw the object into a bitmap buffer.  This is to avoid crashes in
+// [NSGraphicsContext graphicsContextWithGraphicsPort:flipped:] and
+// CGContextDrawImage(), and also to avoid very poor drawing performance in
+// CGContextDrawImage() when it scales the bitmap (particularly if xscale or
+// yscale is less than but near 1 -- e.g. 0.9).  This value was determined
+// by trial and error, on OS X 10.4.11 and 10.5.4, and on systems with
+// different amounts of RAM.
+#define BITMAP_MAX_AREA 500000
+
+static int
+GetBackingScaleFactorForRendering(CGContextRef cgContext)
+{
+  CGAffineTransform ctm = CGContextGetUserSpaceToDeviceSpaceTransform(cgContext);
+  CGRect transformedUserSpacePixel = CGRectApplyAffineTransform(CGRectMake(0, 0, 1, 1), ctm);
+  float maxScale = std::max(fabs(transformedUserSpacePixel.size.width),
+                          fabs(transformedUserSpacePixel.size.height));
+  return maxScale > 1.0 ? 2 : 1;  
+}
+
+/*
+ * Draw the given NSCell into the given cgContext.
+ *
+ * destRect - the size and position of the resulting control rectangle
+ * controlSize - the NSControlSize which will be given to the NSCell before
+ *  asking it to render
+ * naturalSize - The natural dimensions of this control.
+ *  If the control rect size is not equal to either of these, a scale
+ *  will be applied to the context so that rendering the control at the
+ *  natural size will result in it filling the destRect space.
+ *  If a control has no natural dimensions in either/both axes, pass 0.0f.
+ * minimumSize - The minimum dimensions of this control.
+ *  If the control rect size is less than the minimum for a given axis,
+ *  a scale will be applied to the context so that the minimum is used
+ *  for drawing.  If a control has no minimum dimensions in either/both
+ *  axes, pass 0.0f.
+ * marginSet - an array of margins; a multidimensional array of [2][3][4],
+ *  with the first dimension being the OS version (Tiger or Leopard),
+ *  the second being the control size (mini, small, regular), and the third
+ *  being the 4 margin values (left, top, right, bottom).
+ * view - The NSView that we're drawing into. As far as I can tell, it doesn't
+ *  matter if this is really the right view; it just has to return YES when
+ *  asked for isFlipped. Otherwise we'll get drawing bugs on 10.4.
+ * mirrorHorizontal - whether to mirror the cell horizontally
+ */
+static void DrawCellWithScaling(NSCell *cell,
+                                CGContextRef cgContext,
+                                const HIRect& destRect,
+                                NSControlSize controlSize,
+                                NSSize naturalSize,
+                                NSSize minimumSize,
+                                const float marginSet[][3][4],
+                                NSView* view,
+                                BOOL mirrorHorizontal)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NSRect drawRect = NSMakeRect(destRect.origin.x, destRect.origin.y, destRect.size.width, destRect.size.height);
+
+  if (naturalSize.width != 0.0f)
+    drawRect.size.width = naturalSize.width;
+  if (naturalSize.height != 0.0f)
+    drawRect.size.height = naturalSize.height;
+
+  // Keep aspect ratio when scaling if one dimension is free.
+  if (naturalSize.width == 0.0f && naturalSize.height != 0.0f)
+    drawRect.size.width = destRect.size.width * naturalSize.height / destRect.size.height;
+  if (naturalSize.height == 0.0f && naturalSize.width != 0.0f)
+    drawRect.size.height = destRect.size.height * naturalSize.width / destRect.size.width;
+
+  // Honor minimum sizes.
+  if (drawRect.size.width < minimumSize.width)
+    drawRect.size.width = minimumSize.width;
+  if (drawRect.size.height < minimumSize.height)
+    drawRect.size.height = minimumSize.height;
+
+  [NSGraphicsContext saveGraphicsState];
+
+  // Only skip the buffer if the area of our cell (in pixels^2) is too large.
+  if (drawRect.size.width * drawRect.size.height > BITMAP_MAX_AREA) {
+    // Inflate the rect Gecko gave us by the margin for the control.
+    InflateControlRect(&drawRect, controlSize, marginSet);
+
+    NSGraphicsContext* savedContext = [NSGraphicsContext currentContext];
+    [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:cgContext flipped:YES]];
+
+    DrawCellIncludingFocusRing(cell, drawRect, view);
+
+    [NSGraphicsContext setCurrentContext:savedContext];
+  }
+  else {
+    float w = ceil(drawRect.size.width);
+    float h = ceil(drawRect.size.height);
+    NSRect tmpRect = NSMakeRect(kMaxFocusRingWidth, kMaxFocusRingWidth, w, h);
+
+    // inflate to figure out the frame we need to tell NSCell to draw in, to get something that's 0,0,w,h
+    InflateControlRect(&tmpRect, controlSize, marginSet);
+
+    // and then, expand by kMaxFocusRingWidth size to make sure we can capture any focus ring
+    w += kMaxFocusRingWidth * 2.0;
+    h += kMaxFocusRingWidth * 2.0;
+
+    int backingScaleFactor = GetBackingScaleFactorForRendering(cgContext);
+    CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
+    CGContextRef ctx = CGBitmapContextCreate(NULL,
+                                             (int) w * backingScaleFactor, (int) h * backingScaleFactor,
+                                             8, (int) w * backingScaleFactor * 4,
+                                             rgb, kCGImageAlphaPremultipliedFirst);
+    CGColorSpaceRelease(rgb);
+
+    // We need to flip the image twice in order to avoid drawing bugs on 10.4, see bug 465069.
+    // This is the first flip transform, applied to cgContext.
+    CGContextScaleCTM(cgContext, 1.0f, -1.0f);
+    CGContextTranslateCTM(cgContext, 0.0f, -(2.0 * destRect.origin.y + destRect.size.height));
+    if (mirrorHorizontal) {
+      CGContextScaleCTM(cgContext, -1.0f, 1.0f);
+      CGContextTranslateCTM(cgContext, -(2.0 * destRect.origin.x + destRect.size.width), 0.0f);
+    }
+
+    NSGraphicsContext* savedContext = [NSGraphicsContext currentContext];
+    [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:ctx flipped:YES]];
+
+    CGContextScaleCTM(ctx, backingScaleFactor, backingScaleFactor);
+
+    // Set the context's "base transform" to in order to get correctly-sized focus rings.
+    CGContextSetBaseCTM(ctx, CGAffineTransformMakeScale(backingScaleFactor, backingScaleFactor));
+
+    // This is the second flip transform, applied to ctx.
+    CGContextScaleCTM(ctx, 1.0f, -1.0f);
+    CGContextTranslateCTM(ctx, 0.0f, -(2.0 * tmpRect.origin.y + tmpRect.size.height));
+
+    DrawCellIncludingFocusRing(cell, tmpRect, view);
+
+    [NSGraphicsContext setCurrentContext:savedContext];
+
+    CGImageRef img = CGBitmapContextCreateImage(ctx);
+
+    // Drop the image into the original destination rectangle, scaling to fit
+    // Only scale kMaxFocusRingWidth by xscale/yscale when the resulting rect
+    // doesn't extend beyond the overflow rect
+    float xscale = destRect.size.width / drawRect.size.width;
+    float yscale = destRect.size.height / drawRect.size.height;
+    float scaledFocusRingX = xscale < 1.0f ? kMaxFocusRingWidth * xscale : kMaxFocusRingWidth;
+    float scaledFocusRingY = yscale < 1.0f ? kMaxFocusRingWidth * yscale : kMaxFocusRingWidth;
+    CGContextDrawImage(cgContext, CGRectMake(destRect.origin.x - scaledFocusRingX,
+                                             destRect.origin.y - scaledFocusRingY,
+                                             destRect.size.width + scaledFocusRingX * 2,
+                                             destRect.size.height + scaledFocusRingY * 2),
+                       img);
+
+    CGImageRelease(img);
+    CGContextRelease(ctx);
+  }
+
+  [NSGraphicsContext restoreGraphicsState];
+
+#if DRAW_IN_FRAME_DEBUG
+  CGContextSetRGBFillColor(cgContext, 0.0, 0.0, 0.5, 0.25);
+  CGContextFillRect(cgContext, destRect);
+#endif
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+struct CellRenderSettings {
+  // The natural dimensions of the control.
+  // If a control has no natural dimensions in either/both axes, set to 0.0f.
+  NSSize naturalSizes[3];
+
+  // The minimum dimensions of the control.
+  // If a control has no minimum dimensions in either/both axes, set to 0.0f.
+  NSSize minimumSizes[3];
+
+  // A three-dimensional array,
+  // with the first dimension being the OS version ([0] 10.6-10.9, [1] 10.10 and above),
+  // the second being the control size (mini, small, regular), and the third
+  // being the 4 margin values (left, top, right, bottom).
+  float margins[2][3][4];
+};
+
+/*
+ * This is a helper method that returns the required NSControlSize given a size
+ * and the size of the three controls plus a tolerance.
+ * size - The width or the height of the element to draw.
+ * sizes - An array with the all the width/height of the element for its
+ *         different sizes.
+ * tolerance - The tolerance as passed to DrawCellWithSnapping.
+ * NOTE: returns NSRegularControlSize if all values in 'sizes' are zero.
+ */
+static NSControlSize FindControlSize(CGFloat size, const CGFloat* sizes, CGFloat tolerance)
+{
+  for (uint32_t i = miniControlSize; i <= regularControlSize; ++i) {
+    if (sizes[i] == 0) {
+      continue;
+    }
+
+    CGFloat next = 0;
+    // Find next value.
+    for (uint32_t j = i+1; j <= regularControlSize; ++j) {
+      if (sizes[j] != 0) {
+        next = sizes[j];
+        break;
+      }
+    }
+
+    // If it's the latest value, we pick it.
+    if (next == 0) {
+      return CocoaSizeForEnum(i);
+    }
+
+    if (size <= sizes[i] + tolerance && size < next) {
+      return CocoaSizeForEnum(i);
+    }
+  }
+
+  // If we are here, that means sizes[] was an array with only empty values
+  // or the algorithm above is wrong.
+  // The former can happen but the later would be wrong.
+  NS_ASSERTION(sizes[0] == 0 && sizes[1] == 0 && sizes[2] == 0,
+               "We found no control! We shouldn't be there!");
+  return CocoaSizeForEnum(regularControlSize);
+}
+
+/*
+ * Draw the given NSCell into the given cgContext with a nice control size.
+ *
+ * This function is similar to DrawCellWithScaling, but it decides what
+ * control size to use based on the destRect's size.
+ * Scaling is only applied when the difference between the destRect's size
+ * and the next smaller natural size is greater than snapTolerance. Otherwise
+ * it snaps to the next smaller control size without scaling because unscaled
+ * controls look nicer.
+ */
+static void DrawCellWithSnapping(NSCell *cell,
+                                 CGContextRef cgContext,
+                                 const HIRect& destRect,
+                                 const CellRenderSettings settings,
+                                 float verticalAlignFactor,
+                                 NSView* view,
+                                 BOOL mirrorHorizontal,
+                                 float snapTolerance = 2.0f)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  const float rectWidth = destRect.size.width, rectHeight = destRect.size.height;
+  const NSSize *sizes = settings.naturalSizes;
+  const NSSize miniSize = sizes[EnumSizeForCocoaSize(NSMiniControlSize)];
+  const NSSize smallSize = sizes[EnumSizeForCocoaSize(NSSmallControlSize)];
+  const NSSize regularSize = sizes[EnumSizeForCocoaSize(NSRegularControlSize)];
+
+  HIRect drawRect = destRect;
+
+  CGFloat controlWidths[3] = { miniSize.width, smallSize.width, regularSize.width };
+  NSControlSize controlSizeX = FindControlSize(rectWidth, controlWidths, snapTolerance);
+  CGFloat controlHeights[3] = { miniSize.height, smallSize.height, regularSize.height };
+  NSControlSize controlSizeY = FindControlSize(rectHeight, controlHeights, snapTolerance);
+
+  NSControlSize controlSize = NSRegularControlSize;
+  size_t sizeIndex = 0;
+
+  // At some sizes, don't scale but snap.
+  const NSControlSize smallerControlSize =
+    EnumSizeForCocoaSize(controlSizeX) < EnumSizeForCocoaSize(controlSizeY) ?
+    controlSizeX : controlSizeY;
+  const size_t smallerControlSizeIndex = EnumSizeForCocoaSize(smallerControlSize);
+  const NSSize size = sizes[smallerControlSizeIndex];
+  float diffWidth = size.width ? rectWidth - size.width : 0.0f;
+  float diffHeight = size.height ? rectHeight - size.height : 0.0f;
+  if (diffWidth >= 0.0f && diffHeight >= 0.0f &&
+      diffWidth <= snapTolerance && diffHeight <= snapTolerance) {
+    // Snap to the smaller control size.
+    controlSize = smallerControlSize;
+    sizeIndex = smallerControlSizeIndex;
+    MOZ_ASSERT(sizeIndex < ArrayLength(settings.naturalSizes));
+
+    // Resize and center the drawRect.
+    if (sizes[sizeIndex].width) {
+      drawRect.origin.x += ceil((destRect.size.width - sizes[sizeIndex].width) / 2);
+      drawRect.size.width = sizes[sizeIndex].width;
+    }
+    if (sizes[sizeIndex].height) {
+      drawRect.origin.y += floor((destRect.size.height - sizes[sizeIndex].height) * verticalAlignFactor);
+      drawRect.size.height = sizes[sizeIndex].height;
+    }
+  } else {
+    // Use the larger control size.
+    controlSize = EnumSizeForCocoaSize(controlSizeX) > EnumSizeForCocoaSize(controlSizeY) ?
+                  controlSizeX : controlSizeY;
+    sizeIndex = EnumSizeForCocoaSize(controlSize);
+   }
+
+  [cell setControlSize:controlSize];
+
+  MOZ_ASSERT(sizeIndex < ArrayLength(settings.minimumSizes));
+  const NSSize minimumSize = settings.minimumSizes[sizeIndex];
+  DrawCellWithScaling(cell, cgContext, drawRect, controlSize, sizes[sizeIndex],
+                      minimumSize, settings.margins, view, mirrorHorizontal);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@interface NSWindow(CoreUIRendererPrivate)
++ (CUIRendererRef)coreUIRenderer;
+@end
+
+static id
+GetAquaAppearance()
+{
+  // We only need NSAppearance on 10.10 and up.
+  if (nsCocoaFeatures::OnYosemiteOrLater()) {
+    Class NSAppearanceClass = NSClassFromString(@"NSAppearance");
+    if (NSAppearanceClass &&
+        [NSAppearanceClass respondsToSelector:@selector(appearanceNamed:)]) {
+      return [NSAppearanceClass performSelector:@selector(appearanceNamed:)
+                                     withObject:@"NSAppearanceNameAqua"];
+    }
+  }
+  return nil;
+}
+
+@interface NSObject(NSAppearanceCoreUIRendering)
+- (void)_drawInRect:(CGRect)rect context:(CGContextRef)cgContext options:(id)options;
+@end
+
+static void
+RenderWithCoreUI(CGRect aRect, CGContextRef cgContext, NSDictionary* aOptions, bool aSkipAreaCheck = false)
+{
+  id appearance = GetAquaAppearance();
+
+  if (!aSkipAreaCheck && aRect.size.width * aRect.size.height > BITMAP_MAX_AREA) {
+    return;
+  }
+
+  if (appearance && [appearance respondsToSelector:@selector(_drawInRect:context:options:)]) {
+    // Render through NSAppearance on Mac OS 10.10 and up. This will call
+    // CUIDraw with a CoreUI renderer that will give us the correct 10.10
+    // style. Calling CUIDraw directly with [NSWindow coreUIRenderer] still
+    // renders 10.9-style widgets on 10.10.
+    [appearance _drawInRect:aRect context:cgContext options:aOptions];
+  } else {
+    // 10.9 and below
+    CUIRendererRef renderer = [NSWindow respondsToSelector:@selector(coreUIRenderer)]
+      ? [NSWindow coreUIRenderer] : nil;
+    CUIDraw(renderer, aRect, cgContext, (CFDictionaryRef)aOptions, NULL);
+  }
+}
+
+static float VerticalAlignFactor(nsIFrame *aFrame)
+{
+  if (!aFrame)
+    return 0.5f; // default: center
+
+  const nsStyleCoord& va = aFrame->StyleDisplay()->mVerticalAlign;
+  uint8_t intval = (va.GetUnit() == eStyleUnit_Enumerated)
+                     ? va.GetIntValue()
+                     : NS_STYLE_VERTICAL_ALIGN_MIDDLE;
+  switch (intval) {
+    case NS_STYLE_VERTICAL_ALIGN_TOP:
+    case NS_STYLE_VERTICAL_ALIGN_TEXT_TOP:
+      return 0.0f;
+
+    case NS_STYLE_VERTICAL_ALIGN_SUB:
+    case NS_STYLE_VERTICAL_ALIGN_SUPER:
+    case NS_STYLE_VERTICAL_ALIGN_MIDDLE:
+    case NS_STYLE_VERTICAL_ALIGN_MIDDLE_WITH_BASELINE:
+      return 0.5f;
+
+    case NS_STYLE_VERTICAL_ALIGN_BASELINE:
+    case NS_STYLE_VERTICAL_ALIGN_TEXT_BOTTOM:
+    case NS_STYLE_VERTICAL_ALIGN_BOTTOM:
+      return 1.0f;
+
+    default:
+      NS_NOTREACHED("invalid vertical-align");
+      return 0.5f;
+  }
+}
+
+// These are the sizes that Gecko needs to request to draw if it wants
+// to get a standard-sized Aqua radio button drawn. Note that the rects
+// that draw these are actually a little bigger.
+static const CellRenderSettings radioSettings = {
+  {
+    NSMakeSize(11, 11), // mini
+    NSMakeSize(13, 13), // small
+    NSMakeSize(16, 16)  // regular
+  },
+  {
+    NSZeroSize, NSZeroSize, NSZeroSize
+  },
+  {
+    { // Leopard
+      {0, 0, 0, 0},     // mini
+      {0, 1, 1, 1},     // small
+      {0, 0, 0, 0}      // regular
+    },
+    { // Yosemite
+      {0, 0, 0, 0},     // mini
+      {1, 1, 1, 2},     // small
+      {0, 0, 0, 0}      // regular
+    }
+  }
+};
+
+static const CellRenderSettings checkboxSettings = {
+  {
+    NSMakeSize(11, 11), // mini
+    NSMakeSize(13, 13), // small
+    NSMakeSize(16, 16)  // regular
+  },
+  {
+    NSZeroSize, NSZeroSize, NSZeroSize
+  },
+  {
+    { // Leopard
+      {0, 1, 0, 0},     // mini
+      {0, 1, 0, 1},     // small
+      {0, 1, 0, 1}      // regular
+    },
+    { // Yosemite
+      {0, 1, 0, 0},     // mini
+      {0, 1, 0, 1},     // small
+      {0, 1, 0, 1}      // regular
+    }
+  }
+};
+
+void
+nsNativeThemeCocoa::DrawCheckboxOrRadio(CGContextRef cgContext, bool inCheckbox,
+                                        const HIRect& inBoxRect, bool inSelected,
+                                        EventStates inState, nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NSButtonCell *cell = inCheckbox ? mCheckboxCell : mRadioButtonCell;
+  NSCellStateValue state = inSelected ? NSOnState : NSOffState;
+
+  // Check if we have an indeterminate checkbox
+  if (inCheckbox && GetIndeterminate(aFrame))
+    state = NSMixedState;
+
+  [cell setEnabled:!IsDisabled(aFrame, inState)];
+  [cell setShowsFirstResponder:inState.HasState(NS_EVENT_STATE_FOCUS)];
+  [cell setState:state];
+  [cell setHighlighted:inState.HasAllStates(NS_EVENT_STATE_ACTIVE | NS_EVENT_STATE_HOVER)];
+  [cell setControlTint:(FrameIsInActiveWindow(aFrame) ? [NSColor currentControlTint] : NSClearControlTint)];
+
+  // Ensure that the control is square.
+  float length = std::min(inBoxRect.size.width, inBoxRect.size.height);
+  HIRect drawRect = CGRectMake(inBoxRect.origin.x + (int)((inBoxRect.size.width - length) / 2.0f),
+                               inBoxRect.origin.y + (int)((inBoxRect.size.height - length) / 2.0f),
+                               length, length);
+
+  DrawCellWithSnapping(cell, cgContext, drawRect,
+                       inCheckbox ? checkboxSettings : radioSettings,
+                       VerticalAlignFactor(aFrame), mCellDrawView, NO);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const CellRenderSettings searchFieldSettings = {
+  {
+    NSMakeSize(0, 16), // mini
+    NSMakeSize(0, 19), // small
+    NSMakeSize(0, 22)  // regular
+  },
+  {
+    NSMakeSize(32, 0), // mini
+    NSMakeSize(38, 0), // small
+    NSMakeSize(44, 0)  // regular
+  },
+  {
+    { // Leopard
+      {0, 0, 0, 0},     // mini
+      {0, 0, 0, 0},     // small
+      {0, 0, 0, 0}      // regular
+    },
+    { // Yosemite
+      {0, 0, 0, 0},     // mini
+      {0, 0, 0, 0},     // small
+      {0, 0, 0, 0}      // regular
+    }
+  }
+};
+
+void
+nsNativeThemeCocoa::DrawSearchField(CGContextRef cgContext, const HIRect& inBoxRect,
+                                    nsIFrame* aFrame, EventStates inState)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  ContextAwareSearchFieldCell* cell = mSearchFieldCell;
+  [cell setContext:aFrame];
+  [cell setEnabled:!IsDisabled(aFrame, inState)];
+  // NOTE: this could probably use inState
+  [cell setShowsFirstResponder:IsFocused(aFrame)];
+
+  // When using the 10.11 SDK, the default string will be shown if we don't
+  // set the placeholder string.
+  [cell setPlaceholderString:@""];
+
+  DrawCellWithSnapping(cell, cgContext, inBoxRect, searchFieldSettings,
+                       VerticalAlignFactor(aFrame), mCellDrawView,
+                       IsFrameRTL(aFrame));
+
+  [cell setContext:nullptr];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const NSSize kCheckmarkSize = NSMakeSize(11, 11);
+static const NSSize kMenuarrowSize = NSMakeSize(9, 10);
+static const NSSize kMenuScrollArrowSize = NSMakeSize(10, 8);
+static NSString* kCheckmarkImage = @"MenuOnState";
+static NSString* kMenuarrowRightImage = @"MenuSubmenu";
+static NSString* kMenuarrowLeftImage = @"MenuSubmenuLeft";
+static NSString* kMenuDownScrollArrowImage = @"MenuScrollDown";
+static NSString* kMenuUpScrollArrowImage = @"MenuScrollUp";
+static const CGFloat kMenuIconIndent = 6.0f;
+
+void
+nsNativeThemeCocoa::DrawMenuIcon(CGContextRef cgContext, const CGRect& aRect,
+                                 EventStates inState, nsIFrame* aFrame,
+                                 const NSSize& aIconSize, NSString* aImageName,
+                                 bool aCenterHorizontally)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Adjust size and position of our drawRect.
+  CGFloat paddingX = std::max(CGFloat(0.0), aRect.size.width - aIconSize.width);
+  CGFloat paddingY = std::max(CGFloat(0.0), aRect.size.height - aIconSize.height);
+  CGFloat paddingStartX = std::min(paddingX, kMenuIconIndent);
+  CGFloat paddingEndX = std::max(CGFloat(0.0), paddingX - kMenuIconIndent);
+  CGRect drawRect = CGRectMake(
+    aRect.origin.x + (aCenterHorizontally ? ceil(paddingX / 2) :
+                      IsFrameRTL(aFrame) ? paddingEndX : paddingStartX),
+    aRect.origin.y + ceil(paddingY / 2),
+    aIconSize.width, aIconSize.height);
+
+  NSString* state = IsDisabled(aFrame, inState) ? @"disabled" :
+    (CheckBooleanAttr(aFrame, nsGkAtoms::menuactive) ? @"pressed" : @"normal");
+
+  NSString* imageName = aImageName;
+  if (!nsCocoaFeatures::OnElCapitanOrLater()) {
+    // Pre-10.11, image names are prefixed with "image."
+    imageName = [@"image." stringByAppendingString:aImageName];
+  }
+
+  RenderWithCoreUI(drawRect, cgContext,
+          [NSDictionary dictionaryWithObjectsAndKeys:
+            @"kCUIBackgroundTypeMenu", @"backgroundTypeKey",
+            imageName, @"imageNameKey",
+            state, @"state",
+            @"image", @"widget",
+            [NSNumber numberWithBool:YES], @"is.flipped",
+            nil]);
+
+#if DRAW_IN_FRAME_DEBUG
+  CGContextSetRGBFillColor(cgContext, 0.0, 0.0, 0.5, 0.25);
+  CGContextFillRect(cgContext, drawRect);
+#endif
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const NSSize kHelpButtonSize = NSMakeSize(20, 20);
+static const NSSize kDisclosureButtonSize = NSMakeSize(21, 21);
+
+static const CellRenderSettings pushButtonSettings = {
+  {
+    NSMakeSize(0, 16), // mini
+    NSMakeSize(0, 19), // small
+    NSMakeSize(0, 22)  // regular
+  },
+  {
+    NSMakeSize(18, 0), // mini
+    NSMakeSize(26, 0), // small
+    NSMakeSize(30, 0)  // regular
+  },
+  {
+    { // Leopard
+      {0, 0, 0, 0},    // mini
+      {4, 0, 4, 1},    // small
+      {5, 0, 5, 2}     // regular
+    },
+    { // Yosemite
+      {0, 0, 0, 0},    // mini
+      {4, 0, 4, 1},    // small
+      {5, 0, 5, 2}     // regular
+    }
+  }
+};
+
+// The height at which we start doing square buttons instead of rounded buttons
+// Rounded buttons look bad if drawn at a height greater than 26, so at that point
+// we switch over to doing square buttons which looks fine at any size.
+#define DO_SQUARE_BUTTON_HEIGHT 26
+
+void
+nsNativeThemeCocoa::DrawPushButton(CGContextRef cgContext, const HIRect& inBoxRect,
+                                   EventStates inState, uint8_t aWidgetType,
+                                   nsIFrame* aFrame, float aOriginalHeight)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  BOOL isActive = FrameIsInActiveWindow(aFrame);
+  BOOL isDisabled = IsDisabled(aFrame, inState);
+
+  NSButtonCell* cell = (aWidgetType == NS_THEME_BUTTON) ? mPushButtonCell :
+    (aWidgetType == NS_THEME_MAC_HELP_BUTTON) ? mHelpButtonCell : mDisclosureButtonCell;
+  [cell setEnabled:!isDisabled];
+  [cell setHighlighted:isActive &&
+                       inState.HasAllStates(NS_EVENT_STATE_ACTIVE | NS_EVENT_STATE_HOVER)];
+  [cell setShowsFirstResponder:inState.HasState(NS_EVENT_STATE_FOCUS) && !isDisabled && isActive];
+
+  if (aWidgetType != NS_THEME_BUTTON) { // Help button or disclosure button.
+    NSSize buttonSize = NSMakeSize(0, 0);
+    if (aWidgetType == NS_THEME_MAC_HELP_BUTTON) {
+      buttonSize = kHelpButtonSize;
+    } else { // Disclosure button.
+      buttonSize = kDisclosureButtonSize;
+      [cell setState:(aWidgetType == NS_THEME_MAC_DISCLOSURE_BUTTON_CLOSED) ? NSOffState : NSOnState];
+    }
+
+    DrawCellWithScaling(cell, cgContext, inBoxRect, NSRegularControlSize,
+                        NSZeroSize, buttonSize, NULL, mCellDrawView,
+                        false); // Don't mirror icon in RTL.
+  } else {
+    // If the button is tall enough, draw the square button style so that
+    // buttons with non-standard content look good. Otherwise draw normal
+    // rounded aqua buttons.
+    // This comparison is done based on the height that is calculated without
+    // the top, because the snapped height can be affected by the top of the
+    // rect and that may result in different height depending on the top value.
+    if (aOriginalHeight > DO_SQUARE_BUTTON_HEIGHT) {
+      [cell setBezelStyle:NSShadowlessSquareBezelStyle];
+      DrawCellWithScaling(cell, cgContext, inBoxRect, NSRegularControlSize,
+                          NSZeroSize, NSMakeSize(14, 0), NULL, mCellDrawView,
+                          IsFrameRTL(aFrame));
+    } else {
+      [cell setBezelStyle:NSRoundedBezelStyle];
+      DrawCellWithSnapping(cell, cgContext, inBoxRect, pushButtonSettings, 0.5f,
+                           mCellDrawView, IsFrameRTL(aFrame), 1.0f);
+    }
+  }
+
+#if DRAW_IN_FRAME_DEBUG
+  CGContextSetRGBFillColor(cgContext, 0.0, 0.0, 0.5, 0.25);
+  CGContextFillRect(cgContext, inBoxRect);
+#endif
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsNativeThemeCocoa::DrawFocusOutline(CGContextRef cgContext, const HIRect& inBoxRect,
+                                     EventStates inState, uint8_t aWidgetType,
+                                     nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  HIThemeFrameDrawInfo fdi;
+  fdi.version = 0;
+  fdi.kind = kHIThemeFrameTextFieldSquare;
+  fdi.state = kThemeStateActive;
+  fdi.isFocused = TRUE;
+
+#if DRAW_IN_FRAME_DEBUG
+  CGContextSetRGBFillColor(cgContext, 0.0, 0.0, 0.5, 0.25);
+  CGContextFillRect(cgContext, inBoxRect);
+#endif
+
+  HIThemeDrawFrame(&inBoxRect, &fdi, cgContext, HITHEME_ORIENTATION);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+typedef void (*RenderHIThemeControlFunction)(CGContextRef cgContext, const HIRect& aRenderRect, void* aData);
+
+static void
+RenderTransformedHIThemeControl(CGContextRef aCGContext, const HIRect& aRect,
+                                RenderHIThemeControlFunction aFunc, void* aData,
+                                BOOL mirrorHorizontally = NO)
+{
+  CGAffineTransform savedCTM = CGContextGetCTM(aCGContext);
+  CGContextTranslateCTM(aCGContext, aRect.origin.x, aRect.origin.y);
+
+  bool drawDirect;
+  HIRect drawRect = aRect;
+  drawRect.origin = CGPointZero;
+
+  if (!mirrorHorizontally && savedCTM.a == 1.0f && savedCTM.b == 0.0f &&
+      savedCTM.c == 0.0f && (savedCTM.d == 1.0f || savedCTM.d == -1.0f)) {
+    drawDirect = TRUE;
+  } else {
+    drawDirect = FALSE;
+  }
+
+  // Fall back to no bitmap buffer if the area of our control (in pixels^2)
+  // is too large.
+  if (drawDirect || (aRect.size.width * aRect.size.height > BITMAP_MAX_AREA)) {
+    aFunc(aCGContext, drawRect, aData);
+  } else {
+    // Inflate the buffer to capture focus rings.
+    int w = ceil(drawRect.size.width) + 2 * kMaxFocusRingWidth;
+    int h = ceil(drawRect.size.height) + 2 * kMaxFocusRingWidth;
+
+    int backingScaleFactor = GetBackingScaleFactorForRendering(aCGContext);
+    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
+    CGContextRef bitmapctx = CGBitmapContextCreate(NULL,
+                                                   w * backingScaleFactor,
+                                                   h * backingScaleFactor,
+                                                   8,
+                                                   w * backingScaleFactor * 4,
+                                                   colorSpace,
+                                                   kCGImageAlphaPremultipliedFirst);
+    CGColorSpaceRelease(colorSpace);
+
+    CGContextScaleCTM(bitmapctx, backingScaleFactor, backingScaleFactor);
+    CGContextTranslateCTM(bitmapctx, kMaxFocusRingWidth, kMaxFocusRingWidth);
+
+    // Set the context's "base transform" to in order to get correctly-sized focus rings.
+    CGContextSetBaseCTM(bitmapctx, CGAffineTransformMakeScale(backingScaleFactor, backingScaleFactor));
+
+    // HITheme always wants to draw into a flipped context, or things
+    // get confused.
+    CGContextTranslateCTM(bitmapctx, 0.0f, aRect.size.height);
+    CGContextScaleCTM(bitmapctx, 1.0f, -1.0f);
+
+    aFunc(bitmapctx, drawRect, aData);
+
+    CGImageRef bitmap = CGBitmapContextCreateImage(bitmapctx);
+
+    CGAffineTransform ctm = CGContextGetCTM(aCGContext);
+
+    // We need to unflip, so that we can do a DrawImage without getting a flipped image.
+    CGContextTranslateCTM(aCGContext, 0.0f, aRect.size.height);
+    CGContextScaleCTM(aCGContext, 1.0f, -1.0f);
+
+    if (mirrorHorizontally) {
+      CGContextTranslateCTM(aCGContext, aRect.size.width, 0);
+      CGContextScaleCTM(aCGContext, -1.0f, 1.0f);
+    }
+
+    HIRect inflatedDrawRect = CGRectMake(-kMaxFocusRingWidth, -kMaxFocusRingWidth, w, h);
+    CGContextDrawImage(aCGContext, inflatedDrawRect, bitmap);
+
+    CGContextSetCTM(aCGContext, ctm);
+
+    CGImageRelease(bitmap);
+    CGContextRelease(bitmapctx);
+  }
+
+  CGContextSetCTM(aCGContext, savedCTM);
+}
+
+static void
+RenderButton(CGContextRef cgContext, const HIRect& aRenderRect, void* aData)
+{
+  HIThemeButtonDrawInfo* bdi = (HIThemeButtonDrawInfo*)aData;
+  HIThemeDrawButton(&aRenderRect, bdi, cgContext, kHIThemeOrientationNormal, NULL);
+}
+
+void
+nsNativeThemeCocoa::DrawButton(CGContextRef cgContext, ThemeButtonKind inKind,
+                               const HIRect& inBoxRect, bool inIsDefault,
+                               ThemeButtonValue inValue, ThemeButtonAdornment inAdornment,
+                               EventStates inState, nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  BOOL isActive = FrameIsInActiveWindow(aFrame);
+  BOOL isDisabled = IsDisabled(aFrame, inState);
+
+  HIThemeButtonDrawInfo bdi;
+  bdi.version = 0;
+  bdi.kind = inKind;
+  bdi.value = inValue;
+  bdi.adornment = inAdornment;
+
+  if (isDisabled) {
+    bdi.state = kThemeStateUnavailable;
+  }
+  else if (inState.HasAllStates(NS_EVENT_STATE_ACTIVE | NS_EVENT_STATE_HOVER)) {
+    bdi.state = kThemeStatePressed;
+  }
+  else {
+    if (inKind == kThemeArrowButton)
+      bdi.state = kThemeStateUnavailable; // these are always drawn as unavailable
+    else if (!isActive && inKind == kThemeListHeaderButton)
+      bdi.state = kThemeStateInactive;
+    else
+      bdi.state = kThemeStateActive;
+  }
+
+  if (inState.HasState(NS_EVENT_STATE_FOCUS) && isActive)
+    bdi.adornment |= kThemeAdornmentFocus;
+
+  if (inIsDefault && !isDisabled &&
+      !inState.HasState(NS_EVENT_STATE_ACTIVE)) {
+    bdi.adornment |= kThemeAdornmentDefault;
+    bdi.animation.time.start = 0;
+    bdi.animation.time.current = CFAbsoluteTimeGetCurrent();
+  }
+
+  HIRect drawFrame = inBoxRect;
+
+  if (inKind == kThemePushButton) {
+    drawFrame.size.height -= 2;
+    if (inBoxRect.size.height < pushButtonSettings.naturalSizes[smallControlSize].height) {
+      bdi.kind = kThemePushButtonMini;
+    }
+    else if (inBoxRect.size.height < pushButtonSettings.naturalSizes[regularControlSize].height) {
+      bdi.kind = kThemePushButtonSmall;
+      drawFrame.origin.y -= 1;
+      drawFrame.origin.x += 1;
+      drawFrame.size.width -= 2;
+    }
+  }
+  else if (inKind == kThemeListHeaderButton) {
+    CGContextClipToRect(cgContext, inBoxRect);
+    // Always remove the top border.
+    drawFrame.origin.y -= 1;
+    drawFrame.size.height += 1;
+    // Remove the left border in LTR mode and the right border in RTL mode.
+    drawFrame.size.width += 1;
+    bool isLast = IsLastTreeHeaderCell(aFrame);
+    if (isLast)
+      drawFrame.size.width += 1; // Also remove the other border.
+    if (!IsFrameRTL(aFrame) || isLast)
+      drawFrame.origin.x -= 1;
+  }
+
+  RenderTransformedHIThemeControl(cgContext, drawFrame, RenderButton, &bdi,
+                                  IsFrameRTL(aFrame));
+
+#if DRAW_IN_FRAME_DEBUG
+  CGContextSetRGBFillColor(cgContext, 0.0, 0.0, 0.5, 0.25);
+  CGContextFillRect(cgContext, inBoxRect);
+#endif
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const CellRenderSettings dropdownSettings = {
+  {
+    NSMakeSize(0, 16), // mini
+    NSMakeSize(0, 19), // small
+    NSMakeSize(0, 22)  // regular
+  },
+  {
+    NSMakeSize(18, 0), // mini
+    NSMakeSize(38, 0), // small
+    NSMakeSize(44, 0)  // regular
+  },
+  {
+    { // Leopard
+      {1, 1, 2, 1},    // mini
+      {3, 0, 3, 1},    // small
+      {3, 0, 3, 0}     // regular
+    },
+    { // Yosemite
+      {1, 1, 2, 1},    // mini
+      {3, 0, 3, 1},    // small
+      {3, 0, 3, 0}     // regular
+    }
+  }
+};
+
+static const CellRenderSettings editableMenulistSettings = {
+  {
+    NSMakeSize(0, 15), // mini
+    NSMakeSize(0, 18), // small
+    NSMakeSize(0, 21)  // regular
+  },
+  {
+    NSMakeSize(18, 0), // mini
+    NSMakeSize(38, 0), // small
+    NSMakeSize(44, 0)  // regular
+  },
+  {
+    { // Leopard
+      {0, 0, 2, 2},    // mini
+      {0, 0, 3, 2},    // small
+      {0, 1, 3, 3}     // regular
+    },
+    { // Yosemite
+      {0, 0, 2, 2},    // mini
+      {0, 0, 3, 2},    // small
+      {0, 1, 3, 3}     // regular
+    }
+  }
+};
+
+void
+nsNativeThemeCocoa::DrawDropdown(CGContextRef cgContext, const HIRect& inBoxRect,
+                                 EventStates inState, uint8_t aWidgetType,
+                                 nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mDropdownCell setPullsDown:(aWidgetType == NS_THEME_BUTTON)];
+
+  BOOL isEditable = (aWidgetType == NS_THEME_MENULIST_TEXTFIELD);
+  NSCell* cell = isEditable ? (NSCell*)mComboBoxCell : (NSCell*)mDropdownCell;
+
+  [cell setEnabled:!IsDisabled(aFrame, inState)];
+  [cell setShowsFirstResponder:(IsFocused(aFrame) || inState.HasState(NS_EVENT_STATE_FOCUS))];
+  [cell setHighlighted:IsOpenButton(aFrame)];
+  [cell setControlTint:(FrameIsInActiveWindow(aFrame) ? [NSColor currentControlTint] : NSClearControlTint)];
+
+  const CellRenderSettings& settings = isEditable ? editableMenulistSettings : dropdownSettings;
+  DrawCellWithSnapping(cell, cgContext, inBoxRect, settings,
+                       0.5f, mCellDrawView, IsFrameRTL(aFrame));
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const CellRenderSettings spinnerSettings = {
+  {
+    NSMakeSize(11, 16), // mini (width trimmed by 2px to reduce blank border)
+    NSMakeSize(15, 22), // small
+    NSMakeSize(19, 27)  // regular
+  },
+  {
+    NSMakeSize(11, 16), // mini (width trimmed by 2px to reduce blank border)
+    NSMakeSize(15, 22), // small
+    NSMakeSize(19, 27)  // regular
+  },
+  {
+    { // Leopard
+      {0, 0, 0, 0},    // mini
+      {0, 0, 0, 0},    // small
+      {0, 0, 0, 0}     // regular
+    },
+    { // Yosemite
+      {0, 0, 0, 0},    // mini
+      {0, 0, 0, 0},    // small
+      {0, 0, 0, 0}     // regular
+    }
+  }
+};
+
+void
+nsNativeThemeCocoa::DrawSpinButtons(CGContextRef cgContext, ThemeButtonKind inKind,
+                                    const HIRect& inBoxRect, ThemeDrawState inDrawState,
+                                    ThemeButtonAdornment inAdornment,
+                                    EventStates inState, nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  HIThemeButtonDrawInfo bdi;
+  bdi.version = 0;
+  bdi.kind = inKind;
+  bdi.value = kThemeButtonOff;
+  bdi.adornment = inAdornment;
+
+  if (IsDisabled(aFrame, inState))
+    bdi.state = kThemeStateUnavailable;
+  else
+    bdi.state = FrameIsInActiveWindow(aFrame) ? inDrawState : kThemeStateActive;
+
+  HIThemeDrawButton(&inBoxRect, &bdi, cgContext, HITHEME_ORIENTATION, NULL);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsNativeThemeCocoa::DrawSpinButton(CGContextRef cgContext,
+                                   ThemeButtonKind inKind,
+                                   const HIRect& inBoxRect,
+                                   ThemeDrawState inDrawState,
+                                   ThemeButtonAdornment inAdornment,
+                                   EventStates inState,
+                                   nsIFrame* aFrame,
+                                   uint8_t aWidgetType)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  MOZ_ASSERT(aWidgetType == NS_THEME_SPINNER_UPBUTTON ||
+             aWidgetType == NS_THEME_SPINNER_DOWNBUTTON);
+
+  HIThemeButtonDrawInfo bdi;
+  bdi.version = 0;
+  bdi.kind = inKind;
+  bdi.value = kThemeButtonOff;
+  bdi.adornment = inAdornment;
+
+  if (IsDisabled(aFrame, inState))
+    bdi.state = kThemeStateUnavailable;
+  else
+    bdi.state = FrameIsInActiveWindow(aFrame) ? inDrawState : kThemeStateActive;
+
+  // Cocoa only allows kThemeIncDecButton to paint the up and down spin buttons
+  // together as a single unit (presumably because when one button is active,
+  // the appearance of both changes (in different ways)). Here we have to paint
+  // both buttons, using clip to hide the one we don't want to paint.
+  HIRect drawRect = inBoxRect;
+  drawRect.size.height *= 2;
+  if (aWidgetType == NS_THEME_SPINNER_DOWNBUTTON) {
+    drawRect.origin.y -= inBoxRect.size.height;
+  }
+
+  // Shift the drawing a little to the left, since cocoa paints with more
+  // blank space around the visual buttons than we'd like:
+  drawRect.origin.x -= 1;
+
+  CGContextSaveGState(cgContext);
+  CGContextClipToRect(cgContext, inBoxRect);
+
+  HIThemeDrawButton(&drawRect, &bdi, cgContext, HITHEME_ORIENTATION, NULL);
+
+  CGContextRestoreGState(cgContext);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsNativeThemeCocoa::DrawFrame(CGContextRef cgContext, HIThemeFrameKind inKind,
+                              const HIRect& inBoxRect, bool inDisabled,
+                              EventStates inState)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  HIThemeFrameDrawInfo fdi;
+  fdi.version = 0;
+  fdi.kind = inKind;
+
+  // We don't ever set an inactive state for this because it doesn't
+  // look right (see other apps).
+  fdi.state = inDisabled ? kThemeStateUnavailable : kThemeStateActive;
+
+  // for some reason focus rings on listboxes draw incorrectly
+  if (inKind == kHIThemeFrameListBox)
+    fdi.isFocused = 0;
+  else
+    fdi.isFocused = inState.HasState(NS_EVENT_STATE_FOCUS);
+
+  // HIThemeDrawFrame takes the rect for the content area of the frame, not
+  // the bounding rect for the frame. Here we reduce the size of the rect we
+  // will pass to make it the size of the content.
+  HIRect drawRect = inBoxRect;
+  if (inKind == kHIThemeFrameTextFieldSquare) {
+    SInt32 frameOutset = 0;
+    ::GetThemeMetric(kThemeMetricEditTextFrameOutset, &frameOutset);
+    drawRect.origin.x += frameOutset;
+    drawRect.origin.y += frameOutset;
+    drawRect.size.width -= frameOutset * 2;
+    drawRect.size.height -= frameOutset * 2;
+  }
+  else if (inKind == kHIThemeFrameListBox) {
+    SInt32 frameOutset = 0;
+    ::GetThemeMetric(kThemeMetricListBoxFrameOutset, &frameOutset);
+    drawRect.origin.x += frameOutset;
+    drawRect.origin.y += frameOutset;
+    drawRect.size.width -= frameOutset * 2;
+    drawRect.size.height -= frameOutset * 2;
+  }
+
+#if DRAW_IN_FRAME_DEBUG
+  CGContextSetRGBFillColor(cgContext, 0.0, 0.0, 0.5, 0.25);
+  CGContextFillRect(cgContext, inBoxRect);
+#endif
+
+  HIThemeDrawFrame(&drawRect, &fdi, cgContext, HITHEME_ORIENTATION);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const CellRenderSettings progressSettings[2][2] = {
+  // Vertical progress bar.
+  {
+    // Determined settings.
+    {
+      {
+        NSZeroSize, // mini
+        NSMakeSize(10, 0), // small
+        NSMakeSize(16, 0)  // regular
+      },
+      {
+        NSZeroSize, NSZeroSize, NSZeroSize
+      },
+      {
+        { // Leopard
+          {0, 0, 0, 0},     // mini
+          {1, 1, 1, 1},     // small
+          {1, 1, 1, 1}      // regular
+        }
+      }
+    },
+    // There is no horizontal margin in regular undetermined size.
+    {
+      {
+        NSZeroSize, // mini
+        NSMakeSize(10, 0), // small
+        NSMakeSize(16, 0)  // regular
+      },
+      {
+        NSZeroSize, NSZeroSize, NSZeroSize
+      },
+      {
+        { // Leopard
+          {0, 0, 0, 0},     // mini
+          {1, 1, 1, 1},     // small
+          {1, 0, 1, 0}      // regular
+        },
+        { // Yosemite
+          {0, 0, 0, 0},     // mini
+          {1, 1, 1, 1},     // small
+          {1, 0, 1, 0}      // regular
+        }
+      }
+    }
+  },
+  // Horizontal progress bar.
+  {
+    // Determined settings.
+    {
+      {
+        NSZeroSize, // mini
+        NSMakeSize(0, 10), // small
+        NSMakeSize(0, 16)  // regular
+      },
+      {
+        NSZeroSize, NSZeroSize, NSZeroSize
+      },
+      {
+        { // Leopard
+          {0, 0, 0, 0},     // mini
+          {1, 1, 1, 1},     // small
+          {1, 1, 1, 1}      // regular
+        },
+        { // Yosemite
+          {0, 0, 0, 0},     // mini
+          {1, 1, 1, 1},     // small
+          {1, 1, 1, 1}      // regular
+        }
+      }
+    },
+    // There is no horizontal margin in regular undetermined size.
+    {
+      {
+        NSZeroSize, // mini
+        NSMakeSize(0, 10), // small
+        NSMakeSize(0, 16)  // regular
+      },
+      {
+        NSZeroSize, NSZeroSize, NSZeroSize
+      },
+      {
+        { // Leopard
+          {0, 0, 0, 0},     // mini
+          {1, 1, 1, 1},     // small
+          {0, 1, 0, 1}      // regular
+        },
+        { // Yosemite
+          {0, 0, 0, 0},     // mini
+          {1, 1, 1, 1},     // small
+          {0, 1, 0, 1}      // regular
+        }
+      }
+    }
+  }
+};
+
+void
+nsNativeThemeCocoa::DrawProgress(CGContextRef cgContext, const HIRect& inBoxRect,
+                                 bool inIsIndeterminate, bool inIsHorizontal,
+                                 double inValue, double inMaxValue,
+                                 nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  NSProgressBarCell* cell = mProgressBarCell;
+
+  [cell setValue:inValue];
+  [cell setMax:inMaxValue];
+  [cell setIndeterminate:inIsIndeterminate];
+  [cell setHorizontal:inIsHorizontal];
+  [cell setControlTint:(FrameIsInActiveWindow(aFrame) ? [NSColor currentControlTint]
+                                                      : NSClearControlTint)];
+
+  DrawCellWithSnapping(cell, cgContext, inBoxRect,
+                       progressSettings[inIsHorizontal][inIsIndeterminate],
+                       VerticalAlignFactor(aFrame), mCellDrawView,
+                       IsFrameRTL(aFrame));
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static const CellRenderSettings meterSetting = {
+  {
+    NSMakeSize(0, 16), // mini
+    NSMakeSize(0, 16), // small
+    NSMakeSize(0, 16)  // regular
+  },
+  {
+    NSZeroSize, NSZeroSize, NSZeroSize
+  },
+  {
+    { // Leopard
+      {1, 1, 1, 1},     // mini
+      {1, 1, 1, 1},     // small
+      {1, 1, 1, 1}      // regular
+    },
+    { // Yosemite
+      {1, 1, 1, 1},     // mini
+      {1, 1, 1, 1},     // small
+      {1, 1, 1, 1}      // regular
+    }
+  }
+};
+
+void
+nsNativeThemeCocoa::DrawMeter(CGContextRef cgContext, const HIRect& inBoxRect,
+                              nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK
+
+  NS_PRECONDITION(aFrame, "aFrame should not be null here!");
+
+  // When using -moz-meterbar on an non meter element, we will not be able to
+  // get all the needed information so we just draw an empty meter.
+  nsIContent* content = aFrame->GetContent();
+  if (!(content && content->IsHTMLElement(nsGkAtoms::meter))) {
+    DrawCellWithSnapping(mMeterBarCell, cgContext, inBoxRect,
+                         meterSetting, VerticalAlignFactor(aFrame),
+                         mCellDrawView, IsFrameRTL(aFrame));
+    return;
+  }
+
+  HTMLMeterElement* meterElement = static_cast<HTMLMeterElement*>(content);
+  double value = meterElement->Value();
+  double min = meterElement->Min();
+  double max = meterElement->Max();
+
+  NSLevelIndicatorCell* cell = mMeterBarCell;
+
+  [cell setMinValue:min];
+  [cell setMaxValue:max];
+  [cell setDoubleValue:value];
+
+  /**
+   * The way HTML and Cocoa defines the meter/indicator widget are different.
+   * So, we are going to use a trick to get the Cocoa widget showing what we
+   * are expecting: we set the warningValue or criticalValue to the current
+   * value when we want to have the widget to be in the warning or critical
+   * state.
+   */
+  EventStates states = aFrame->GetContent()->AsElement()->State();
+
+  // Reset previously set warning and critical values.
+  [cell setWarningValue:max+1];
+  [cell setCriticalValue:max+1];
+
+  if (states.HasState(NS_EVENT_STATE_SUB_OPTIMUM)) {
+    [cell setWarningValue:value];
+  } else if (states.HasState(NS_EVENT_STATE_SUB_SUB_OPTIMUM)) {
+    [cell setCriticalValue:value];
+  }
+
+  HIRect rect = CGRectStandardize(inBoxRect);
+  BOOL vertical = IsVerticalMeter(aFrame);
+
+  CGContextSaveGState(cgContext);
+
+  if (vertical) {
+    /**
+     * Cocoa doesn't provide a vertical meter bar so to show one, we have to
+     * show a rotated horizontal meter bar.
+     * Given that we want to show a vertical meter bar, we assume that the rect
+     * has vertical dimensions but we can't correctly draw a meter widget inside
+     * such a rectangle so we need to inverse width and height (and re-position)
+     * to get a rectangle with horizontal dimensions.
+     * Finally, we want to show a vertical meter so we want to rotate the result
+     * so it is vertical. We do that by changing the context.
+     */
+    CGFloat tmp = rect.size.width;
+    rect.size.width = rect.size.height;
+    rect.size.height = tmp;
+    rect.origin.x += rect.size.height / 2.f - rect.size.width / 2.f;
+    rect.origin.y += rect.size.width / 2.f - rect.size.height / 2.f;
+
+    CGContextTranslateCTM(cgContext, CGRectGetMidX(rect), CGRectGetMidY(rect));
+    CGContextRotateCTM(cgContext, -M_PI / 2.f);
+    CGContextTranslateCTM(cgContext, -CGRectGetMidX(rect), -CGRectGetMidY(rect));
+  }
+
+  DrawCellWithSnapping(cell, cgContext, rect,
+                       meterSetting, VerticalAlignFactor(aFrame),
+                       mCellDrawView, !vertical && IsFrameRTL(aFrame));
+
+  CGContextRestoreGState(cgContext);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK
+}
+
+void
+nsNativeThemeCocoa::DrawTabPanel(CGContextRef cgContext, const HIRect& inBoxRect,
+                                 nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  HIThemeTabPaneDrawInfo tpdi;
+
+  tpdi.version = 1;
+  tpdi.state = FrameIsInActiveWindow(aFrame) ? kThemeStateActive : kThemeStateInactive;
+  tpdi.direction = kThemeTabNorth;
+  tpdi.size = kHIThemeTabSizeNormal;
+  tpdi.kind = kHIThemeTabKindNormal;
+
+  HIThemeDrawTabPane(&inBoxRect, &tpdi, cgContext, HITHEME_ORIENTATION);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsNativeThemeCocoa::DrawScale(CGContextRef cgContext, const HIRect& inBoxRect,
+                              EventStates inState, bool inIsVertical,
+                              bool inIsReverse, int32_t inCurrentValue,
+                              int32_t inMinValue, int32_t inMaxValue,
+                              nsIFrame* aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  HIThemeTrackDrawInfo tdi;
+
+  tdi.version = 0;
+  tdi.kind = kThemeMediumSlider;
+  tdi.bounds = inBoxRect;
+  tdi.min = inMinValue;
+  tdi.max = inMaxValue;
+  tdi.value = inCurrentValue;
+  tdi.attributes = kThemeTrackShowThumb;
+  if (!inIsVertical)
+    tdi.attributes |= kThemeTrackHorizontal;
+  if (inIsReverse)
+    tdi.attributes |= kThemeTrackRightToLeft;
+  if (inState.HasState(NS_EVENT_STATE_FOCUS))
+    tdi.attributes |= kThemeTrackHasFocus;
+  if (IsDisabled(aFrame, inState))
+    tdi.enableState = kThemeTrackDisabled;
+  else
+    tdi.enableState = FrameIsInActiveWindow(aFrame) ? kThemeTrackActive : kThemeTrackInactive;
+  tdi.trackInfo.slider.thumbDir = kThemeThumbPlain;
+  tdi.trackInfo.slider.pressState = 0;
+
+  HIThemeDrawTrack(&tdi, NULL, cgContext, HITHEME_ORIENTATION);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsIFrame*
+nsNativeThemeCocoa::SeparatorResponsibility(nsIFrame* aBefore, nsIFrame* aAfter)
+{
+  // Usually a separator is drawn by the segment to the right of the
+  // separator, but pressed and selected segments have higher priority.
+  if (!aBefore || !aAfter)
+    return nullptr;
+  if (IsSelectedButton(aAfter))
+    return aAfter;
+  if (IsSelectedButton(aBefore) || IsPressedButton(aBefore))
+    return aBefore;
+  return aAfter;
+}
+
+CGRect
+nsNativeThemeCocoa::SeparatorAdjustedRect(CGRect aRect, nsIFrame* aLeft,
+                                          nsIFrame* aCurrent, nsIFrame* aRight)
+{
+  // A separator between two segments should always be located in the leftmost
+  // pixel column of the segment to the right of the separator, regardless of
+  // who ends up drawing it.
+  // CoreUI draws the separators inside the drawing rect.
+  if (aLeft && SeparatorResponsibility(aLeft, aCurrent) == aLeft) {
+    // The left button draws the separator, so we need to make room for it.
+    aRect.origin.x += 1;
+    aRect.size.width -= 1;
+  }
+  if (SeparatorResponsibility(aCurrent, aRight) == aCurrent) {
+    // We draw the right separator, so we need to extend the draw rect into the
+    // segment to our right.
+    aRect.size.width += 1;
+  }
+  return aRect;
+}
+
+static NSString* ToolbarButtonPosition(BOOL aIsFirst, BOOL aIsLast)
+{
+  if (aIsFirst) {
+    if (aIsLast)
+      return @"kCUISegmentPositionOnly";
+    return @"kCUISegmentPositionFirst";
+  }
+  if (aIsLast)
+    return @"kCUISegmentPositionLast";
+  return @"kCUISegmentPositionMiddle";
+}
+
+struct SegmentedControlRenderSettings {
+  const CGFloat* heights;
+  const NSString* widgetName;
+  const BOOL ignoresPressedWhenSelected;
+  const BOOL isToolbarControl;
+};
+
+static const CGFloat tabHeights[3] = { 17, 20, 23 };
+
+static const SegmentedControlRenderSettings tabRenderSettings = {
+  tabHeights, @"tab", YES, NO
+};
+
+static const CGFloat toolbarButtonHeights[3] = { 15, 18, 22 };
+
+static const SegmentedControlRenderSettings toolbarButtonRenderSettings = {
+  toolbarButtonHeights, @"kCUIWidgetButtonSegmentedSCurve", NO, YES
+};
+
+void
+nsNativeThemeCocoa::DrawSegment(CGContextRef cgContext, const HIRect& inBoxRect,
+                                EventStates inState, nsIFrame* aFrame,
+                                const SegmentedControlRenderSettings& aSettings)
+{
+  BOOL isActive = IsActive(aFrame, aSettings.isToolbarControl);
+  BOOL isFocused = inState.HasState(NS_EVENT_STATE_FOCUS);
+  BOOL isSelected = IsSelectedButton(aFrame);
+  BOOL isPressed = IsPressedButton(aFrame);
+  if (isSelected && aSettings.ignoresPressedWhenSelected) {
+    isPressed = NO;
+  }
+
+  BOOL isRTL = IsFrameRTL(aFrame);
+  nsIFrame* left = GetAdjacentSiblingFrameWithSameAppearance(aFrame, isRTL);
+  nsIFrame* right = GetAdjacentSiblingFrameWithSameAppearance(aFrame, !isRTL);
+  CGRect drawRect = SeparatorAdjustedRect(inBoxRect, left, aFrame, right);
+  BOOL drawLeftSeparator = SeparatorResponsibility(left, aFrame) == aFrame;
+  BOOL drawRightSeparator = SeparatorResponsibility(aFrame, right) == aFrame;
+  NSControlSize controlSize = FindControlSize(drawRect.size.height, aSettings.heights, 4.0f);
+
+  RenderWithCoreUI(drawRect, cgContext, [NSDictionary dictionaryWithObjectsAndKeys:
+            aSettings.widgetName, @"widget",
+            (isActive ? @"kCUIPresentationStateActiveKey" : @"kCUIPresentationStateInactive"), @"kCUIPresentationStateKey",
+            ToolbarButtonPosition(!left, !right), @"kCUIPositionKey",
+            [NSNumber numberWithBool:drawLeftSeparator], @"kCUISegmentLeadingSeparatorKey",
+            [NSNumber numberWithBool:drawRightSeparator], @"kCUISegmentTrailingSeparatorKey",
+            [NSNumber numberWithBool:isSelected], @"value",
+            (isPressed ? @"pressed" : (isActive ? @"normal" : @"inactive")), @"state",
+            [NSNumber numberWithBool:isFocused], @"focus",
+            CUIControlSizeForCocoaSize(controlSize), @"size",
+            [NSNumber numberWithBool:YES], @"is.flipped",
+            @"up", @"direction",
+            nil]);
+}
+
+void 
+nsNativeThemeCocoa::GetScrollbarPressStates(nsIFrame* aFrame,
+                                            EventStates aButtonStates[])
+{
+  static nsIContent::AttrValuesArray attributeValues[] = {
+    &nsGkAtoms::scrollbarUpTop,
+    &nsGkAtoms::scrollbarDownTop,
+    &nsGkAtoms::scrollbarUpBottom,
+    &nsGkAtoms::scrollbarDownBottom,
+    nullptr
+  };
+
+  // Get the state of any scrollbar buttons in our child frames
+  for (nsIFrame *childFrame : aFrame->PrincipalChildList()) {
+    nsIContent *childContent = childFrame->GetContent();
+    if (!childContent) continue;
+    int32_t attrIndex = childContent->FindAttrValueIn(kNameSpaceID_None, nsGkAtoms::sbattr, 
+                                                      attributeValues, eCaseMatters);
+    if (attrIndex < 0) continue;
+
+    aButtonStates[attrIndex] = GetContentState(childFrame, NS_THEME_BUTTON);
+  }
+}
+
+nsIFrame*
+nsNativeThemeCocoa::GetParentScrollbarFrame(nsIFrame *aFrame)
+{
+  // Walk our parents to find a scrollbar frame
+  nsIFrame *scrollbarFrame = aFrame;
+  do {
+    if (scrollbarFrame->GetType() == nsGkAtoms::scrollbarFrame) break;
+  } while ((scrollbarFrame = scrollbarFrame->GetParent()));
+
+  // We return null if we can't find a parent scrollbar frame
+  return scrollbarFrame;
+}
+
+static bool
+ToolbarCanBeUnified(CGContextRef cgContext, const HIRect& inBoxRect, NSWindow* aWindow)
+{
+  if (![aWindow isKindOfClass:[ToolbarWindow class]])
+    return false;
+
+  ToolbarWindow* win = (ToolbarWindow*)aWindow;
+  float unifiedToolbarHeight = [win unifiedToolbarHeight];
+  return inBoxRect.origin.x == 0 &&
+         inBoxRect.size.width >= [win frame].size.width &&
+         CGRectGetMaxY(inBoxRect) <= unifiedToolbarHeight;
+}
+
+// By default, kCUIWidgetWindowFrame drawing draws rounded corners in the
+// upper corners. Depending on the context type, it fills the background in
+// the corners with black or leaves it transparent. Unfortunately, this corner
+// rounding interacts poorly with the window corner masking we apply during
+// titlebar drawing and results in small remnants of the corner background
+// appearing at the rounded edge.
+// So we draw square corners.
+static void
+DrawNativeTitlebarToolbarWithSquareCorners(CGContextRef aContext, const CGRect& aRect,
+                                           CGFloat aUnifiedHeight, BOOL aIsMain, BOOL aIsFlipped)
+{
+  // We extend the draw rect horizontally and clip away the rounded corners.
+  const CGFloat extendHorizontal = 10;
+  CGRect drawRect = CGRectInset(aRect, -extendHorizontal, 0);
+  CGContextSaveGState(aContext);
+  CGContextClipToRect(aContext, aRect);
+
+  RenderWithCoreUI(drawRect, aContext,
+          [NSDictionary dictionaryWithObjectsAndKeys:
+            @"kCUIWidgetWindowFrame", @"widget",
+            @"regularwin", @"windowtype",
+            (aIsMain ? @"normal" : @"inactive"), @"state",
+            [NSNumber numberWithDouble:aUnifiedHeight], @"kCUIWindowFrameUnifiedTitleBarHeightKey",
+            [NSNumber numberWithBool:YES], @"kCUIWindowFrameDrawTitleSeparatorKey",
+            [NSNumber numberWithBool:aIsFlipped], @"is.flipped",
+            nil]);
+
+  CGContextRestoreGState(aContext);
+}
+
+void
+nsNativeThemeCocoa::DrawUnifiedToolbar(CGContextRef cgContext, const HIRect& inBoxRect,
+                                       NSWindow* aWindow)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  CGContextSaveGState(cgContext);
+  CGContextClipToRect(cgContext, inBoxRect);
+
+  CGFloat unifiedHeight = std::max([(ToolbarWindow*)aWindow unifiedToolbarHeight],
+                                   inBoxRect.size.height);
+  BOOL isMain = [aWindow isMainWindow];
+  CGFloat titlebarHeight = unifiedHeight - inBoxRect.size.height;
+  CGRect drawRect = CGRectMake(inBoxRect.origin.x, inBoxRect.origin.y - titlebarHeight,
+                               inBoxRect.size.width, inBoxRect.size.height + titlebarHeight);
+  DrawNativeTitlebarToolbarWithSquareCorners(cgContext, drawRect, unifiedHeight, isMain, YES);
+
+  CGContextRestoreGState(cgContext);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsNativeThemeCocoa::DrawStatusBar(CGContextRef cgContext, const HIRect& inBoxRect,
+                                  nsIFrame *aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (inBoxRect.size.height < 2.0f)
+    return;
+
+  CGContextSaveGState(cgContext);
+  CGContextClipToRect(cgContext, inBoxRect);
+
+  // kCUIWidgetWindowFrame draws a complete window frame with both title bar
+  // and bottom bar. We only want the bottom bar, so we extend the draw rect
+  // upwards to make space for the title bar, and then we clip it away.
+  CGRect drawRect = inBoxRect;
+  const int extendUpwards = 40;
+  drawRect.origin.y -= extendUpwards;
+  drawRect.size.height += extendUpwards;
+  RenderWithCoreUI(drawRect, cgContext,
+          [NSDictionary dictionaryWithObjectsAndKeys:
+            @"kCUIWidgetWindowFrame", @"widget",
+            @"regularwin", @"windowtype",
+            (IsActive(aFrame, YES) ? @"normal" : @"inactive"), @"state",
+            [NSNumber numberWithInt:inBoxRect.size.height], @"kCUIWindowFrameBottomBarHeightKey",
+            [NSNumber numberWithBool:YES], @"kCUIWindowFrameDrawBottomBarSeparatorKey",
+            [NSNumber numberWithBool:YES], @"is.flipped",
+            nil]);
+
+  CGContextRestoreGState(cgContext);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsNativeThemeCocoa::DrawNativeTitlebar(CGContextRef aContext, CGRect aTitlebarRect,
+                                       CGFloat aUnifiedHeight, BOOL aIsMain, BOOL aIsFlipped)
+{
+  CGFloat unifiedHeight = std::max(aUnifiedHeight, aTitlebarRect.size.height);
+  DrawNativeTitlebarToolbarWithSquareCorners(aContext, aTitlebarRect, unifiedHeight, aIsMain, aIsFlipped);
+}
+
+static void
+RenderResizer(CGContextRef cgContext, const HIRect& aRenderRect, void* aData)
+{
+  HIThemeGrowBoxDrawInfo* drawInfo = (HIThemeGrowBoxDrawInfo*)aData;
+  HIThemeDrawGrowBox(&CGPointZero, drawInfo, cgContext, kHIThemeOrientationNormal);
+}
+
+void
+nsNativeThemeCocoa::DrawResizer(CGContextRef cgContext, const HIRect& aRect,
+                                nsIFrame *aFrame)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  HIThemeGrowBoxDrawInfo drawInfo;
+  drawInfo.version = 0;
+  drawInfo.state = kThemeStateActive;
+  drawInfo.kind = kHIThemeGrowBoxKindNormal;
+  drawInfo.direction = kThemeGrowRight | kThemeGrowDown;
+  drawInfo.size = kHIThemeGrowBoxSizeNormal;
+
+  RenderTransformedHIThemeControl(cgContext, aRect, RenderResizer, &drawInfo,
+                                  IsFrameRTL(aFrame));
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+static void
+DrawVibrancyBackground(CGContextRef cgContext, CGRect inBoxRect,
+                       nsIFrame* aFrame, nsITheme::ThemeGeometryType aThemeGeometryType,
+                       int aCornerRadiusIfOpaque = 0)
+{
+  ChildView* childView = ChildViewForFrame(aFrame);
+  if (childView) {
+    NSRect rect = NSRectFromCGRect(inBoxRect);
+    NSGraphicsContext* savedContext = [NSGraphicsContext currentContext];
+    [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:cgContext flipped:YES]];
+    [NSGraphicsContext saveGraphicsState];
+
+    NSColor* fillColor = [childView vibrancyFillColorForThemeGeometryType:aThemeGeometryType];
+    if ([fillColor alphaComponent] == 1.0 && aCornerRadiusIfOpaque > 0) {
+      // The fillColor being opaque means that the system-wide pref "reduce
+      // transparency" is set. In that scenario, we still go through all the
+      // vibrancy rendering paths (VibrancyManager::SystemSupportsVibrancy()
+      // will still return true), but the result just won't look "vibrant".
+      // However, there's one unfortunate change of behavior that this pref
+      // has: It stops the window server from applying window masks. We use
+      // a window mask to get rounded corners on menus. So since the mask
+      // doesn't work in "reduce vibrancy" mode, we need to do our own rounded
+      // corner clipping here.
+      [[NSBezierPath bezierPathWithRoundedRect:rect
+                                       xRadius:aCornerRadiusIfOpaque
+                                       yRadius:aCornerRadiusIfOpaque] addClip];
+    }
+
+    [fillColor set];
+    NSRectFill(rect);
+
+    [NSGraphicsContext restoreGraphicsState];
+    [NSGraphicsContext setCurrentContext:savedContext];
+  }
+}
+
+bool
+nsNativeThemeCocoa::IsParentScrollbarRolledOver(nsIFrame* aFrame)
+{
+  nsIFrame* scrollbarFrame = GetParentScrollbarFrame(aFrame);
+  return nsLookAndFeel::UseOverlayScrollbars()
+    ? CheckBooleanAttr(scrollbarFrame, nsGkAtoms::hover)
+    : GetContentState(scrollbarFrame, NS_THEME_NONE).HasState(NS_EVENT_STATE_HOVER);
+}
+
+static bool
+IsHiDPIContext(nsPresContext* aContext)
+{
+  return nsPresContext::AppUnitsPerCSSPixel() >=
+    2 * aContext->DeviceContext()->AppUnitsPerDevPixelAtUnitFullZoom();
+}
+
+static bool
+IsScrollbarWidthThin(nsIFrame* aFrame)
+{
+  return aFrame->StyleUserInterface()->mScrollbarWidth == StyleScrollbarWidth::Thin;
+}
+
+NS_IMETHODIMP
+nsNativeThemeCocoa::DrawWidgetBackground(nsRenderingContext* aContext,
+                                         nsIFrame* aFrame,
+                                         uint8_t aWidgetType,
+                                         const nsRect& aRect,
+                                         const nsRect& aDirtyRect)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  DrawTarget& aDrawTarget = *aContext->GetDrawTarget();
+
+  // setup to draw into the correct port
+  int32_t p2a = aFrame->PresContext()->AppUnitsPerDevPixel();
+
+  gfx::Rect nativeDirtyRect = NSRectToRect(aDirtyRect, p2a);
+  gfxRect nativeWidgetRect(aRect.x, aRect.y, aRect.width, aRect.height);
+  nativeWidgetRect.ScaleInverse(gfxFloat(p2a));
+  float nativeWidgetHeight = round(nativeWidgetRect.Height());
+  nativeWidgetRect.Round();
+  if (nativeWidgetRect.IsEmpty())
+    return NS_OK; // Don't attempt to draw invisible widgets.
+
+  AutoRestoreTransform autoRestoreTransform(&aDrawTarget);
+
+  bool hidpi = IsHiDPIContext(aFrame->PresContext());
+  if (hidpi) {
+    // Use high-resolution drawing.
+    nativeWidgetRect.Scale(0.5f);
+    nativeWidgetHeight *= 0.5f;
+    nativeDirtyRect.Scale(0.5f);
+    aDrawTarget.SetTransform(aDrawTarget.GetTransform().PreScale(2.0f, 2.0f));
+  }
+
+  gfxQuartzNativeDrawing nativeDrawing(aDrawTarget, nativeDirtyRect);
+
+  CGContextRef cgContext = nativeDrawing.BeginNativeDrawing();
+  if (cgContext == nullptr) {
+    // The Quartz surface handles 0x0 surfaces by internally
+    // making all operations no-ops; there's no cgcontext created for them.
+    // Unfortunately, this means that callers that want to render
+    // directly to the CGContext need to be aware of this quirk.
+    return NS_OK;
+  }
+
+  if (hidpi) {
+    // Set the context's "base transform" to in order to get correctly-sized focus rings.
+    CGContextSetBaseCTM(cgContext, CGAffineTransformMakeScale(2, 2));
+  }
+
+#if 0
+  if (1 /*aWidgetType == NS_THEME_TEXTFIELD*/) {
+    fprintf(stderr, "Native theme drawing widget %d [%p] dis:%d in rect [%d %d %d %d]\n",
+            aWidgetType, aFrame, IsDisabled(aFrame), aRect.x, aRect.y, aRect.width, aRect.height);
+    fprintf(stderr, "Cairo matrix: [%f %f %f %f %f %f]\n",
+            mat._11, mat._12, mat._21, mat._22, mat._31, mat._32);
+    fprintf(stderr, "Native theme xform[0]: [%f %f %f %f %f %f]\n",
+            mm0.a, mm0.b, mm0.c, mm0.d, mm0.tx, mm0.ty);
+    CGAffineTransform mm = CGContextGetCTM(cgContext);
+    fprintf(stderr, "Native theme xform[1]: [%f %f %f %f %f %f]\n",
+            mm.a, mm.b, mm.c, mm.d, mm.tx, mm.ty);
+  }
+#endif
+
+  CGRect macRect = CGRectMake(nativeWidgetRect.X(), nativeWidgetRect.Y(),
+                              nativeWidgetRect.Width(), nativeWidgetRect.Height());
+
+#if 0
+  fprintf(stderr, "    --> macRect %f %f %f %f\n",
+          macRect.origin.x, macRect.origin.y, macRect.size.width, macRect.size.height);
+  CGRect bounds = CGContextGetClipBoundingBox(cgContext);
+  fprintf(stderr, "    --> clip bounds: %f %f %f %f\n",
+          bounds.origin.x, bounds.origin.y, bounds.size.width, bounds.size.height);
+
+  //CGContextSetRGBFillColor(cgContext, 0.0, 0.0, 1.0, 0.1);
+  //CGContextFillRect(cgContext, bounds);
+#endif
+
+  EventStates eventState = GetContentState(aFrame, aWidgetType);
+
+  switch (aWidgetType) {
+    case NS_THEME_DIALOG: {
+      if (IsWindowSheet(aFrame)) {
+        if (VibrancyManager::SystemSupportsVibrancy()) {
+          ThemeGeometryType type = ThemeGeometryTypeForWidget(aFrame, aWidgetType);
+          DrawVibrancyBackground(cgContext, macRect, aFrame, type);
+        } else {
+          HIThemeSetFill(kThemeBrushSheetBackgroundTransparent, NULL, cgContext, HITHEME_ORIENTATION);
+          CGContextFillRect(cgContext, macRect);
+        }
+      } else {
+        HIThemeSetFill(kThemeBrushDialogBackgroundActive, NULL, cgContext, HITHEME_ORIENTATION);
+        CGContextFillRect(cgContext, macRect);
+      }
+
+    }
+      break;
+
+    case NS_THEME_MENUPOPUP:
+      if (VibrancyManager::SystemSupportsVibrancy()) {
+        DrawVibrancyBackground(cgContext, macRect, aFrame, eThemeGeometryTypeMenu, 4);
+      } else {
+        HIThemeMenuDrawInfo mdi;
+        memset(&mdi, 0, sizeof(mdi));
+        mdi.version = 0;
+        mdi.menuType = IsDisabled(aFrame, eventState) ?
+                         static_cast<ThemeMenuType>(kThemeMenuTypeInactive) :
+                         static_cast<ThemeMenuType>(kThemeMenuTypePopUp);
+
+        bool isLeftOfParent = false;
+        if (IsSubmenu(aFrame, &isLeftOfParent) && !isLeftOfParent) {
+          mdi.menuType = kThemeMenuTypeHierarchical;
+        }
+
+        // The rounded corners draw outside the frame.
+        CGRect deflatedRect = CGRectMake(macRect.origin.x, macRect.origin.y + 4,
+                                         macRect.size.width, macRect.size.height - 8);
+        HIThemeDrawMenuBackground(&deflatedRect, &mdi, cgContext, HITHEME_ORIENTATION);
+      }
+      break;
+
+    case NS_THEME_MENUARROW: {
+      bool isRTL = IsFrameRTL(aFrame);
+      DrawMenuIcon(cgContext, macRect, eventState, aFrame, kMenuarrowSize,
+                   isRTL ? kMenuarrowLeftImage : kMenuarrowRightImage, true);
+    }
+      break;
+
+    case NS_THEME_MENUITEM:
+    case NS_THEME_CHECKMENUITEM: {
+      if (VibrancyManager::SystemSupportsVibrancy()) {
+        ThemeGeometryType type = ThemeGeometryTypeForWidget(aFrame, aWidgetType);
+        DrawVibrancyBackground(cgContext, macRect, aFrame, type);
+      } else {
+        bool isDisabled = IsDisabled(aFrame, eventState);
+        bool isSelected = !isDisabled && CheckBooleanAttr(aFrame, nsGkAtoms::menuactive);
+        // maybe use kThemeMenuItemHierBackground or PopUpBackground instead of just Plain?
+        HIThemeMenuItemDrawInfo drawInfo;
+        memset(&drawInfo, 0, sizeof(drawInfo));
+        drawInfo.version = 0;
+        drawInfo.itemType = kThemeMenuItemPlain;
+        drawInfo.state = (isDisabled ?
+                           static_cast<ThemeMenuState>(kThemeMenuDisabled) :
+                           isSelected ?
+                             static_cast<ThemeMenuState>(kThemeMenuSelected) :
+                             static_cast<ThemeMenuState>(kThemeMenuActive));
+
+        // XXX pass in the menu rect instead of always using the item rect
+        HIRect ignored;
+        HIThemeDrawMenuItem(&macRect, &macRect, &drawInfo, cgContext, HITHEME_ORIENTATION, &ignored);
+      }
+
+      if (aWidgetType == NS_THEME_CHECKMENUITEM) {
+        DrawMenuIcon(cgContext, macRect, eventState, aFrame, kCheckmarkSize, kCheckmarkImage, false);
+      }
+    }
+      break;
+
+    case NS_THEME_MENUSEPARATOR: {
+      // Workaround for visual artifacts issues with
+      // HIThemeDrawMenuSeparator on macOS Big Sur.
+      if (nsCocoaFeatures::OnBigSurOrLater()) {
+        CGRect separatorRect = macRect;
+        separatorRect.size.height = 1;
+        separatorRect.size.width -= 42;
+        separatorRect.origin.x += 21;
+        // Use a gray color similar to the native separator
+        CGContextSetRGBFillColor(cgContext, 0.816, 0.816, 0.816, 1.0);
+        CGContextFillRect(cgContext, separatorRect);
+      }
+      else
+      {
+        ThemeMenuState menuState;
+        if (IsDisabled(aFrame, eventState)) {
+           menuState = kThemeMenuDisabled;
+        }
+        else {
+          menuState = CheckBooleanAttr(aFrame, nsGkAtoms::menuactive) ?
+                      kThemeMenuSelected : kThemeMenuActive;
+        }
+        HIThemeMenuItemDrawInfo midi = { 0, kThemeMenuItemPlain, menuState };
+        HIThemeDrawMenuSeparator(&macRect, &macRect, &midi, cgContext, HITHEME_ORIENTATION);
+      }
+    }
+      break;
+
+    case NS_THEME_BUTTON_ARROW_UP:
+    case NS_THEME_BUTTON_ARROW_DOWN:
+      DrawMenuIcon(cgContext, macRect, eventState, aFrame, kMenuScrollArrowSize,
+                   aWidgetType == NS_THEME_BUTTON_ARROW_UP ?
+                   kMenuUpScrollArrowImage : kMenuDownScrollArrowImage, true);
+      break;
+
+    case NS_THEME_TOOLTIP:
+      if (VibrancyManager::SystemSupportsVibrancy()) {
+        DrawVibrancyBackground(cgContext, macRect, aFrame, ThemeGeometryTypeForWidget(aFrame, aWidgetType));
+      } else {
+        CGContextSetRGBFillColor(cgContext, 0.996, 1.000, 0.792, 0.950);
+        CGContextFillRect(cgContext, macRect);
+      }
+      break;
+
+    case NS_THEME_CHECKBOX:
+    case NS_THEME_RADIO: {
+      bool isCheckbox = (aWidgetType == NS_THEME_CHECKBOX);
+      DrawCheckboxOrRadio(cgContext, isCheckbox, macRect, GetCheckedOrSelected(aFrame, !isCheckbox),
+                          eventState, aFrame);
+    }
+      break;
+
+    case NS_THEME_BUTTON:
+      if (IsDefaultButton(aFrame)) {
+        // Check whether the default button is in a document that does not
+        // match the :-moz-window-inactive pseudoclass. This activeness check
+        // is different from the other "active window" checks in this file
+        // because we absolutely need the button's default button appearance to
+        // be in sync with its text color, and the text color is changed by
+        // such a :-moz-window-inactive rule. (That's because on 10.10 and up,
+        // default buttons in active windows have blue background and white
+        // text, and default buttons in inactive windows have white background
+        // and black text.)
+        EventStates docState = aFrame->GetContent()->OwnerDoc()->GetDocumentState();
+        bool isInActiveWindow = !docState.HasState(NS_DOCUMENT_STATE_WINDOW_INACTIVE);
+        if (!IsDisabled(aFrame, eventState) && isInActiveWindow &&
+            !QueueAnimatedContentForRefresh(aFrame->GetContent(), 10)) {
+          NS_WARNING("Unable to animate button!");
+        }
+        DrawButton(cgContext, kThemePushButton, macRect, isInActiveWindow,
+                   kThemeButtonOff, kThemeAdornmentNone, eventState, aFrame);
+      } else if (IsButtonTypeMenu(aFrame)) {
+        DrawDropdown(cgContext, macRect, eventState, aWidgetType, aFrame);
+      } else {
+        DrawPushButton(cgContext, macRect, eventState, aWidgetType, aFrame,
+                       nativeWidgetHeight);
+      }
+      break;
+
+    case NS_THEME_FOCUS_OUTLINE:
+      DrawFocusOutline(cgContext, macRect, eventState, aWidgetType, aFrame);
+      break;
+
+    case NS_THEME_MAC_HELP_BUTTON:
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_OPEN:
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_CLOSED:
+      DrawPushButton(cgContext, macRect, eventState, aWidgetType, aFrame,
+                     nativeWidgetHeight);
+      break;
+
+    case NS_THEME_BUTTON_BEVEL:
+      DrawButton(cgContext, kThemeMediumBevelButton, macRect,
+                 IsDefaultButton(aFrame), kThemeButtonOff, kThemeAdornmentNone,
+                 eventState, aFrame);
+      break;
+
+    case NS_THEME_SPINNER: {
+      nsIContent* content = aFrame->GetContent();
+      if (content->IsHTMLElement()) {
+        // In HTML the theming for the spin buttons is drawn individually into
+        // their own backgrounds instead of being drawn into the background of
+        // their spinner parent as it is for XUL.
+        break;
+      }
+      ThemeDrawState state = kThemeStateActive;
+      if (content->AttrValueIs(kNameSpaceID_None, nsGkAtoms::state,
+                               NS_LITERAL_STRING("up"), eCaseMatters)) {
+        state = kThemeStatePressedUp;
+      }
+      else if (content->AttrValueIs(kNameSpaceID_None, nsGkAtoms::state,
+                                    NS_LITERAL_STRING("down"), eCaseMatters)) {
+        state = kThemeStatePressedDown;
+      }
+
+      DrawSpinButtons(cgContext, kThemeIncDecButton, macRect, state,
+                      kThemeAdornmentNone, eventState, aFrame);
+    }
+      break;
+
+    case NS_THEME_SPINNER_UPBUTTON:
+    case NS_THEME_SPINNER_DOWNBUTTON: {
+      nsNumberControlFrame* numberControlFrame =
+        nsNumberControlFrame::GetNumberControlFrameForSpinButton(aFrame);
+      if (numberControlFrame) {
+        ThemeDrawState state = kThemeStateActive;
+        if (numberControlFrame->SpinnerUpButtonIsDepressed()) {
+          state = kThemeStatePressedUp;
+        } else if (numberControlFrame->SpinnerDownButtonIsDepressed()) {
+          state = kThemeStatePressedDown;
+        }
+        DrawSpinButton(cgContext, kThemeIncDecButtonMini, macRect, state,
+                       kThemeAdornmentNone, eventState, aFrame, aWidgetType);
+      }
+    }
+      break;
+
+    case NS_THEME_TOOLBARBUTTON:
+      DrawSegment(cgContext, macRect, eventState, aFrame, toolbarButtonRenderSettings);
+      break;
+
+    case NS_THEME_SEPARATOR: {
+      HIThemeSeparatorDrawInfo sdi = { 0, kThemeStateActive };
+      HIThemeDrawSeparator(&macRect, &sdi, cgContext, HITHEME_ORIENTATION);
+    }
+      break;
+
+    case NS_THEME_TOOLBAR: {
+      NSWindow* win = NativeWindowForFrame(aFrame);
+      if (ToolbarCanBeUnified(cgContext, macRect, win)) {
+        DrawUnifiedToolbar(cgContext, macRect, win);
+        break;
+      }
+      BOOL isMain = [win isMainWindow];
+      CGRect drawRect = macRect;
+
+      // top border
+      drawRect.size.height = 1.0f;
+      DrawNativeGreyColorInRect(cgContext, toolbarTopBorderGrey, drawRect, isMain);
+
+      // background
+      drawRect.origin.y += drawRect.size.height;
+      drawRect.size.height = macRect.size.height - 2.0f;
+      DrawNativeGreyColorInRect(cgContext, toolbarFillGrey, drawRect, isMain);
+
+      // bottom border
+      drawRect.origin.y += drawRect.size.height;
+      drawRect.size.height = 1.0f;
+      DrawNativeGreyColorInRect(cgContext, toolbarBottomBorderGrey, drawRect, isMain);
+    }
+      break;
+
+    case NS_THEME_WINDOW_TITLEBAR: {
+      NSWindow* win = NativeWindowForFrame(aFrame);
+      BOOL isMain = [win isMainWindow];
+      float unifiedToolbarHeight = [win isKindOfClass:[ToolbarWindow class]] ?
+        [(ToolbarWindow*)win unifiedToolbarHeight] : macRect.size.height;
+      DrawNativeTitlebar(cgContext, macRect, unifiedToolbarHeight, isMain, YES);
+    }
+      break;
+
+    case NS_THEME_STATUSBAR: 
+      DrawStatusBar(cgContext, macRect, aFrame);
+      break;
+
+    case NS_THEME_MENULIST:
+    case NS_THEME_MENULIST_TEXTFIELD:
+      DrawDropdown(cgContext, macRect, eventState, aWidgetType, aFrame);
+      break;
+
+    case NS_THEME_MENULIST_BUTTON:
+      DrawButton(cgContext, kThemeArrowButton, macRect, false, kThemeButtonOn,
+                 kThemeAdornmentArrowDownArrow, eventState, aFrame);
+      break;
+
+    case NS_THEME_GROUPBOX: {
+      HIThemeGroupBoxDrawInfo gdi = { 0, kThemeStateActive, kHIThemeGroupBoxKindPrimary };
+      HIThemeDrawGroupBox(&macRect, &gdi, cgContext, HITHEME_ORIENTATION);
+      break;
+    }
+
+    case NS_THEME_TEXTFIELD:
+    case NS_THEME_NUMBER_INPUT:
+      // HIThemeSetFill is not available on 10.3
+      CGContextSetRGBFillColor(cgContext, 1.0, 1.0, 1.0, 1.0);
+      CGContextFillRect(cgContext, macRect);
+
+      // XUL textboxes set the native appearance on the containing box, while
+      // concrete focus is set on the html:input element within it. We can
+      // though, check the focused attribute of xul textboxes in this case.
+      // On Mac, focus rings are always shown for textboxes, so we do not need
+      // to check the window's focus ring state here
+      if (aFrame->GetContent()->IsXULElement() && IsFocused(aFrame)) {
+        eventState |= NS_EVENT_STATE_FOCUS;
+      }
+
+      DrawFrame(cgContext, kHIThemeFrameTextFieldSquare, macRect,
+                IsDisabled(aFrame, eventState) || IsReadOnly(aFrame), eventState);
+      break;
+      
+    case NS_THEME_SEARCHFIELD:
+      DrawSearchField(cgContext, macRect, aFrame, eventState);
+      break;
+
+    case NS_THEME_PROGRESSBAR:
+    {
+      double value = GetProgressValue(aFrame);
+      double maxValue = GetProgressMaxValue(aFrame);
+      // Don't request repaints for scrollbars at 100% because those don't animate.
+      if (value < maxValue) {
+        if (!QueueAnimatedContentForRefresh(aFrame->GetContent(), 30)) {
+          NS_WARNING("Unable to animate progressbar!");
+        }
+      }
+      DrawProgress(cgContext, macRect, IsIndeterminateProgress(aFrame, eventState),
+                   !IsVerticalProgress(aFrame),
+                   value, maxValue, aFrame);
+      break;
+    }
+
+    case NS_THEME_PROGRESSBAR_VERTICAL:
+      DrawProgress(cgContext, macRect, IsIndeterminateProgress(aFrame, eventState),
+                   false, GetProgressValue(aFrame),
+                   GetProgressMaxValue(aFrame), aFrame);
+      break;
+
+    case NS_THEME_METERBAR:
+      DrawMeter(cgContext, macRect, aFrame);
+      break;
+
+    case NS_THEME_PROGRESSCHUNK:
+    case NS_THEME_PROGRESSCHUNK_VERTICAL:
+    case NS_THEME_METERCHUNK:
+      // Do nothing: progress and meter bars cases will draw chunks.
+      break;
+
+    case NS_THEME_TREETWISTY:
+      DrawButton(cgContext, kThemeDisclosureButton, macRect, false,
+                 kThemeDisclosureRight, kThemeAdornmentNone, eventState, aFrame);
+      break;
+
+    case NS_THEME_TREETWISTYOPEN:
+      DrawButton(cgContext, kThemeDisclosureButton, macRect, false,
+                 kThemeDisclosureDown, kThemeAdornmentNone, eventState, aFrame);
+      break;
+
+    case NS_THEME_TREEHEADERCELL: {
+      TreeSortDirection sortDirection = GetTreeSortDirection(aFrame);
+      DrawButton(cgContext, kThemeListHeaderButton, macRect, false,
+                 sortDirection == eTreeSortDirection_Natural ? kThemeButtonOff : kThemeButtonOn,
+                 sortDirection == eTreeSortDirection_Ascending ?
+                 kThemeAdornmentHeaderButtonSortUp : kThemeAdornmentNone, eventState, aFrame);
+    }
+      break;
+
+    case NS_THEME_TREEITEM:
+    case NS_THEME_TREEVIEW:
+      // HIThemeSetFill is not available on 10.3
+      // HIThemeSetFill(kThemeBrushWhite, NULL, cgContext, HITHEME_ORIENTATION);
+      CGContextSetRGBFillColor(cgContext, 1.0, 1.0, 1.0, 1.0);
+      CGContextFillRect(cgContext, macRect);
+      break;
+
+    case NS_THEME_TREEHEADER:
+      // do nothing, taken care of by individual header cells
+    case NS_THEME_TREEHEADERSORTARROW:
+      // do nothing, taken care of by treeview header
+    case NS_THEME_TREELINE:
+      // do nothing, these lines don't exist on macos
+      break;
+
+    case NS_THEME_SCALE_HORIZONTAL:
+    case NS_THEME_SCALE_VERTICAL: {
+      int32_t curpos = CheckIntAttr(aFrame, nsGkAtoms::curpos, 0);
+      int32_t minpos = CheckIntAttr(aFrame, nsGkAtoms::minpos, 0);
+      int32_t maxpos = CheckIntAttr(aFrame, nsGkAtoms::maxpos, 100);
+      if (!maxpos)
+        maxpos = 100;
+
+      bool reverse = aFrame->GetContent()->
+        AttrValueIs(kNameSpaceID_None, nsGkAtoms::dir,
+                    NS_LITERAL_STRING("reverse"), eCaseMatters);
+      DrawScale(cgContext, macRect, eventState,
+                (aWidgetType == NS_THEME_SCALE_VERTICAL), reverse,
+                curpos, minpos, maxpos, aFrame);
+    }
+      break;
+
+    case NS_THEME_SCALETHUMB_HORIZONTAL:
+    case NS_THEME_SCALETHUMB_VERTICAL:
+      // do nothing, drawn by scale
+      break;
+
+    case NS_THEME_RANGE: {
+      nsRangeFrame *rangeFrame = do_QueryFrame(aFrame);
+      if (!rangeFrame) {
+        break;
+      }
+      // DrawScale requires integer min, max and value. This is purely for
+      // drawing, so we normalize to a range 0-1000 here.
+      int32_t value = int32_t(rangeFrame->GetValueAsFractionOfRange() * 1000);
+      int32_t min = 0;
+      int32_t max = 1000;
+      bool isVertical = !IsRangeHorizontal(aFrame);
+      bool reverseDir = isVertical || rangeFrame->IsRightToLeft();
+      DrawScale(cgContext, macRect, eventState, isVertical, reverseDir,
+                value, min, max, aFrame);
+      break;
+    }
+
+    case NS_THEME_SCROLLBAR_SMALL:
+    case NS_THEME_SCROLLBAR:
+      break;
+    case NS_THEME_SCROLLBARTHUMB_VERTICAL:
+    case NS_THEME_SCROLLBARTHUMB_HORIZONTAL: {
+      BOOL isOverlay = nsLookAndFeel::UseOverlayScrollbars();
+      BOOL isHorizontal = (aWidgetType == NS_THEME_SCROLLBARTHUMB_HORIZONTAL);
+      BOOL isRolledOver = IsParentScrollbarRolledOver(aFrame);
+      nsIFrame* scrollbarFrame = GetParentScrollbarFrame(aFrame);
+      bool isSmall = (scrollbarFrame && scrollbarFrame->StyleDisplay()->mAppearance == NS_THEME_SCROLLBAR_SMALL);
+      if (isOverlay && !isRolledOver) {
+        if (isHorizontal) {
+          macRect.origin.y += 4;
+          macRect.size.height -= 4;
+        } else {
+          if (aFrame->StyleVisibility()->mDirection !=
+              NS_STYLE_DIRECTION_RTL) {
+            macRect.origin.x += 4;
+          }
+          macRect.size.width -= 4;
+        }
+      }
+      const BOOL isOnTopOfDarkBackground = IsDarkBackground(aFrame);
+      NSMutableDictionary* options = [NSMutableDictionary dictionaryWithObjectsAndKeys:
+        (isOverlay ? @"kCUIWidgetOverlayScrollBar" : @"scrollbar"), @"widget",
+        (isSmall ? @"small" : @"regular"), @"size",
+        (isHorizontal ? @"kCUIOrientHorizontal" : @"kCUIOrientVertical"), @"kCUIOrientationKey",
+        (isOverlay && isOnTopOfDarkBackground ? @"kCUIVariantWhite" : @""), @"kCUIVariantKey",
+        [NSNumber numberWithBool:YES], @"indiconly",
+        [NSNumber numberWithBool:YES], @"kCUIThumbProportionKey",
+        [NSNumber numberWithBool:YES], @"is.flipped",
+        nil];
+      if (isRolledOver) {
+        [options setObject:@"rollover" forKey:@"state"];
+      }
+      RenderWithCoreUI(macRect, cgContext, options, true);
+    }
+      break;
+
+    case NS_THEME_SCROLLBARBUTTON_UP:
+    case NS_THEME_SCROLLBARBUTTON_LEFT:
+#if SCROLLBARS_VISUAL_DEBUG
+      CGContextSetRGBFillColor(cgContext, 1.0, 0, 0, 0.6);
+      CGContextFillRect(cgContext, macRect);
+#endif
+    break;
+    case NS_THEME_SCROLLBARBUTTON_DOWN:
+    case NS_THEME_SCROLLBARBUTTON_RIGHT:
+#if SCROLLBARS_VISUAL_DEBUG
+      CGContextSetRGBFillColor(cgContext, 0, 1.0, 0, 0.6);
+      CGContextFillRect(cgContext, macRect);
+#endif
+    break;
+    case NS_THEME_SCROLLBARTRACK_HORIZONTAL:
+    case NS_THEME_SCROLLBARTRACK_VERTICAL: {
+      BOOL isOverlay = nsLookAndFeel::UseOverlayScrollbars();
+      if (!isOverlay || IsParentScrollbarRolledOver(aFrame)) {
+        BOOL isHorizontal = (aWidgetType == NS_THEME_SCROLLBARTRACK_HORIZONTAL);
+        nsIFrame* scrollbarFrame = GetParentScrollbarFrame(aFrame);
+        bool isSmall = (scrollbarFrame && scrollbarFrame->StyleDisplay()->mAppearance == NS_THEME_SCROLLBAR_SMALL);
+        const BOOL isOnTopOfDarkBackground = IsDarkBackground(aFrame);
+        RenderWithCoreUI(macRect, cgContext,
+                [NSDictionary dictionaryWithObjectsAndKeys:
+                  (isOverlay ? @"kCUIWidgetOverlayScrollBar" : @"scrollbar"), @"widget",
+                  (isSmall ? @"small" : @"regular"), @"size",
+                  (isHorizontal ? @"kCUIOrientHorizontal" : @"kCUIOrientVertical"), @"kCUIOrientationKey",
+                  (isOnTopOfDarkBackground ? @"kCUIVariantWhite" : @""), @"kCUIVariantKey",
+                  [NSNumber numberWithBool:YES], @"noindicator",
+                  [NSNumber numberWithBool:YES], @"kCUIThumbProportionKey",
+                  [NSNumber numberWithBool:YES], @"is.flipped",
+                  nil],
+                true);
+      }
+    }
+      break;
+
+    case NS_THEME_TEXTFIELD_MULTILINE: {
+      // we have to draw this by hand because there is no HITheme value for it
+      CGContextSetRGBFillColor(cgContext, 1.0, 1.0, 1.0, 1.0);
+      
+      CGContextFillRect(cgContext, macRect);
+
+      // #737373 for the top border, #999999 for the rest.
+      float x = macRect.origin.x, y = macRect.origin.y;
+      float w = macRect.size.width, h = macRect.size.height;
+      CGContextSetRGBFillColor(cgContext, 0.4510, 0.4510, 0.4510, 1.0);
+      CGContextFillRect(cgContext, CGRectMake(x, y, w, 1));
+      CGContextSetRGBFillColor(cgContext, 0.6, 0.6, 0.6, 1.0);
+      CGContextFillRect(cgContext, CGRectMake(x, y + 1, 1, h - 1));
+      CGContextFillRect(cgContext, CGRectMake(x + w - 1, y + 1, 1, h - 1));
+      CGContextFillRect(cgContext, CGRectMake(x + 1, y + h - 1, w - 2, 1));
+
+      // draw a focus ring
+      if (eventState.HasState(NS_EVENT_STATE_FOCUS)) {
+        NSGraphicsContext* savedContext = [NSGraphicsContext currentContext];
+        [NSGraphicsContext setCurrentContext:[NSGraphicsContext graphicsContextWithGraphicsPort:cgContext flipped:YES]];
+        CGContextSaveGState(cgContext);
+        NSSetFocusRingStyle(NSFocusRingOnly);
+        NSRectFill(NSRectFromCGRect(macRect));
+        CGContextRestoreGState(cgContext);
+        [NSGraphicsContext setCurrentContext:savedContext];
+      }
+    }
+      break;
+
+    case NS_THEME_LISTBOX: {
+      // We have to draw this by hand because kHIThemeFrameListBox drawing
+      // is buggy on 10.5, see bug 579259.
+      CGContextSetRGBFillColor(cgContext, 1.0, 1.0, 1.0, 1.0);
+      CGContextFillRect(cgContext, macRect);
+
+      // #8E8E8E for the top border, #BEBEBE for the rest.
+      float x = macRect.origin.x, y = macRect.origin.y;
+      float w = macRect.size.width, h = macRect.size.height;
+      CGContextSetRGBFillColor(cgContext, 0.557, 0.557, 0.557, 1.0);
+      CGContextFillRect(cgContext, CGRectMake(x, y, w, 1));
+      CGContextSetRGBFillColor(cgContext, 0.745, 0.745, 0.745, 1.0);
+      CGContextFillRect(cgContext, CGRectMake(x, y + 1, 1, h - 1));
+      CGContextFillRect(cgContext, CGRectMake(x + w - 1, y + 1, 1, h - 1));
+      CGContextFillRect(cgContext, CGRectMake(x + 1, y + h - 1, w - 2, 1));
+    }
+      break;
+
+    case NS_THEME_MAC_SOURCE_LIST: {
+      if (VibrancyManager::SystemSupportsVibrancy()) {
+        ThemeGeometryType type = ThemeGeometryTypeForWidget(aFrame, aWidgetType);
+        DrawVibrancyBackground(cgContext, macRect, aFrame, type);
+      } else {
+        CGGradientRef backgroundGradient;
+        CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
+        CGFloat activeGradientColors[8] = { 0.9137, 0.9294, 0.9490, 1.0,
+                                            0.8196, 0.8471, 0.8784, 1.0 };
+        CGFloat inactiveGradientColors[8] = { 0.9686, 0.9686, 0.9686, 1.0,
+                                              0.9216, 0.9216, 0.9216, 1.0 };
+        CGPoint start = macRect.origin;
+        CGPoint end = CGPointMake(macRect.origin.x,
+                                  macRect.origin.y + macRect.size.height);
+        BOOL isActive = FrameIsInActiveWindow(aFrame);
+        backgroundGradient =
+          CGGradientCreateWithColorComponents(rgb, isActive ? activeGradientColors
+                                                            : inactiveGradientColors, NULL, 2);
+        CGContextDrawLinearGradient(cgContext, backgroundGradient, start, end, 0);
+        CGGradientRelease(backgroundGradient);
+        CGColorSpaceRelease(rgb);
+      }
+    }
+      break;
+
+    case NS_THEME_MAC_SOURCE_LIST_SELECTION:
+    case NS_THEME_MAC_ACTIVE_SOURCE_LIST_SELECTION: {
+      // If we're in XUL tree, we need to rely on the source list's clear
+      // background display item. If we cleared the background behind the
+      // selections, the source list would not pick up the right font
+      // smoothing background. So, to simplify a bit, we only support vibrancy
+      // if we're in a source list.
+      if (VibrancyManager::SystemSupportsVibrancy() && IsInSourceList(aFrame)) {
+        ThemeGeometryType type = ThemeGeometryTypeForWidget(aFrame, aWidgetType);
+        DrawVibrancyBackground(cgContext, macRect, aFrame, type);
+      } else {
+        BOOL isActiveSelection =
+          aWidgetType == NS_THEME_MAC_ACTIVE_SOURCE_LIST_SELECTION;
+        RenderWithCoreUI(macRect, cgContext,
+          [NSDictionary dictionaryWithObjectsAndKeys:
+            [NSNumber numberWithBool:isActiveSelection], @"focus",
+            [NSNumber numberWithBool:YES], @"is.flipped",
+            @"kCUIVariantGradientSideBarSelection", @"kCUIVariantKey",
+            (FrameIsInActiveWindow(aFrame) ? @"normal" : @"inactive"), @"state",
+            @"gradient", @"widget",
+            nil]);
+      }
+    }
+      break;
+    
+    case NS_THEME_TAB:
+      DrawSegment(cgContext, macRect, eventState, aFrame, tabRenderSettings);
+      break;
+
+    case NS_THEME_TABPANELS:
+      DrawTabPanel(cgContext, macRect, aFrame);
+      break;
+
+    case NS_THEME_RESIZER:
+      DrawResizer(cgContext, macRect, aFrame);
+      break;
+
+    case NS_THEME_MAC_VIBRANCY_LIGHT:
+    case NS_THEME_MAC_VIBRANCY_DARK: {
+      ThemeGeometryType type = ThemeGeometryTypeForWidget(aFrame, aWidgetType);
+      DrawVibrancyBackground(cgContext, macRect, aFrame, type);
+      break;
+    }
+  }
+
+  if (hidpi) {
+    // Reset the base CTM.
+    CGContextSetBaseCTM(cgContext, CGAffineTransformIdentity);
+  }
+
+  nativeDrawing.EndNativeDrawing();
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsIntMargin
+nsNativeThemeCocoa::DirectionAwareMargin(const nsIntMargin& aMargin,
+                                         nsIFrame* aFrame)
+{
+  // Assuming aMargin was originally specified for a horizontal LTR context,
+  // reinterpret the values as logical, and then map to physical coords
+  // according to aFrame's actual writing mode.
+  WritingMode wm = aFrame->GetWritingMode();
+  nsMargin m = LogicalMargin(wm, aMargin.top, aMargin.right, aMargin.bottom,
+                             aMargin.left).GetPhysicalMargin(wm);
+  return nsIntMargin(m.top, m.right, m.bottom, m.left);
+}
+
+static const nsIntMargin kAquaDropdownBorder(1, 22, 2, 5);
+static const nsIntMargin kAquaComboboxBorder(3, 20, 3, 4);
+static const nsIntMargin kAquaSearchfieldBorder(3, 5, 2, 19);
+
+NS_IMETHODIMP
+nsNativeThemeCocoa::GetWidgetBorder(nsDeviceContext* aContext, 
+                                    nsIFrame* aFrame,
+                                    uint8_t aWidgetType,
+                                    nsIntMargin* aResult)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  aResult->SizeTo(0, 0, 0, 0);
+
+  switch (aWidgetType) {
+    case NS_THEME_BUTTON:
+    {
+      if (IsButtonTypeMenu(aFrame)) {
+        *aResult = DirectionAwareMargin(kAquaDropdownBorder, aFrame);
+      } else {
+        *aResult = DirectionAwareMargin(nsIntMargin(1, 7, 3, 7), aFrame);
+      }
+      break;
+    }
+
+    case NS_THEME_TOOLBARBUTTON:
+    {
+      *aResult = DirectionAwareMargin(nsIntMargin(1, 4, 1, 4), aFrame);
+      break;
+    }
+
+    case NS_THEME_CHECKBOX:
+    case NS_THEME_RADIO:
+    {
+      // nsFormControlFrame::GetIntrinsicWidth and nsFormControlFrame::GetIntrinsicHeight
+      // assume a border width of 2px.
+      aResult->SizeTo(2, 2, 2, 2);
+      break;
+    }
+
+    case NS_THEME_MENULIST:
+    case NS_THEME_MENULIST_BUTTON:
+      *aResult = DirectionAwareMargin(kAquaDropdownBorder, aFrame);
+      break;
+
+    case NS_THEME_MENULIST_TEXTFIELD:
+      *aResult = DirectionAwareMargin(kAquaComboboxBorder, aFrame);
+      break;
+
+    case NS_THEME_NUMBER_INPUT:
+    case NS_THEME_TEXTFIELD:
+    {
+      SInt32 frameOutset = 0;
+      ::GetThemeMetric(kThemeMetricEditTextFrameOutset, &frameOutset);
+
+      SInt32 textPadding = 0;
+      ::GetThemeMetric(kThemeMetricEditTextWhitespace, &textPadding);
+
+      frameOutset += textPadding;
+
+      aResult->SizeTo(frameOutset, frameOutset, frameOutset, frameOutset);
+      break;
+    }
+
+    case NS_THEME_TEXTFIELD_MULTILINE:
+      aResult->SizeTo(1, 1, 1, 1);
+      break;
+
+    case NS_THEME_SEARCHFIELD:
+      *aResult = DirectionAwareMargin(kAquaSearchfieldBorder, aFrame);
+      break;
+
+    case NS_THEME_LISTBOX:
+    {
+      SInt32 frameOutset = 0;
+      ::GetThemeMetric(kThemeMetricListBoxFrameOutset, &frameOutset);
+      aResult->SizeTo(frameOutset, frameOutset, frameOutset, frameOutset);
+      break;
+    }
+
+    case NS_THEME_SCROLLBARTRACK_HORIZONTAL:
+    case NS_THEME_SCROLLBARTRACK_VERTICAL:
+    {
+      bool isHorizontal = (aWidgetType == NS_THEME_SCROLLBARTRACK_HORIZONTAL);
+      if (nsLookAndFeel::UseOverlayScrollbars()) {
+        if (!nsCocoaFeatures::OnYosemiteOrLater()) {
+          // Pre-10.10, we have to center the thumb rect in the middle of the
+          // scrollbar. Starting with 10.10, the expected rect for thumb
+          // rendering is the full width of the scrollbar.
+          if (isHorizontal) {
+            aResult->top = 2;
+            aResult->bottom = 1;
+          } else {
+            aResult->left = 2;
+            aResult->right = 1;
+          }
+        }
+        // Leave a bit of space at the start and the end on all OS X versions.
+        if (isHorizontal) {
+          aResult->left = 1;
+          aResult->right = 1;
+        } else {
+          aResult->top = 1;
+          aResult->bottom = 1;
+        }
+      }
+
+      break;
+    }
+
+    case NS_THEME_STATUSBAR:
+      aResult->SizeTo(1, 0, 0, 0);
+      break;
+  }
+
+  if (IsHiDPIContext(aFrame->PresContext())) {
+    *aResult = *aResult + *aResult; // doubled
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Return false here to indicate that CSS padding values should be used. There is
+// no reason to make a distinction between padding and border values, just specify
+// whatever values you want in GetWidgetBorder and only use this to return true
+// if you want to override CSS padding values.
+bool
+nsNativeThemeCocoa::GetWidgetPadding(nsDeviceContext* aContext, 
+                                     nsIFrame* aFrame,
+                                     uint8_t aWidgetType,
+                                     nsIntMargin* aResult)
+{
+  // We don't want CSS padding being used for certain widgets.
+  // See bug 381639 for an example of why.
+  switch (aWidgetType) {
+    // Radios and checkboxes return a fixed size in GetMinimumWidgetSize
+    // and have a meaningful baseline, so they can't have
+    // author-specified padding.
+    case NS_THEME_CHECKBOX:
+    case NS_THEME_RADIO:
+      aResult->SizeTo(0, 0, 0, 0);
+      return true;
+  }
+  return false;
+}
+
+bool
+nsNativeThemeCocoa::GetWidgetOverflow(nsDeviceContext* aContext, nsIFrame* aFrame,
+                                      uint8_t aWidgetType, nsRect* aOverflowRect)
+{
+  int32_t p2a = aFrame->PresContext()->AppUnitsPerDevPixel();
+  switch (aWidgetType) {
+    case NS_THEME_BUTTON:
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_OPEN:
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_CLOSED:
+    case NS_THEME_MAC_HELP_BUTTON:
+    case NS_THEME_TOOLBARBUTTON:
+    case NS_THEME_NUMBER_INPUT:
+    case NS_THEME_TEXTFIELD:
+    case NS_THEME_TEXTFIELD_MULTILINE:
+    case NS_THEME_SEARCHFIELD:
+    case NS_THEME_LISTBOX:
+    case NS_THEME_MENULIST:
+    case NS_THEME_MENULIST_BUTTON:
+    case NS_THEME_MENULIST_TEXTFIELD:
+    case NS_THEME_CHECKBOX:
+    case NS_THEME_RADIO:
+    case NS_THEME_TAB:
+    {
+      // We assume that the above widgets can draw a focus ring that will be less than
+      // or equal to 4 pixels thick.
+      nsIntMargin extraSize = nsIntMargin(kMaxFocusRingWidth,
+                                          kMaxFocusRingWidth,
+                                          kMaxFocusRingWidth,
+                                          kMaxFocusRingWidth);
+      nsMargin m(NSIntPixelsToAppUnits(extraSize.top, p2a),
+                 NSIntPixelsToAppUnits(extraSize.right, p2a),
+                 NSIntPixelsToAppUnits(extraSize.bottom, p2a),
+                 NSIntPixelsToAppUnits(extraSize.left, p2a));
+      aOverflowRect->Inflate(m);
+      return true;
+    }
+    case NS_THEME_PROGRESSBAR:
+    {
+      // Progress bars draw a 2 pixel white shadow under their progress indicators
+      nsMargin m(0, 0, NSIntPixelsToAppUnits(2, p2a), 0);
+      aOverflowRect->Inflate(m);
+      return true;
+    }
+    case NS_THEME_FOCUS_OUTLINE:
+    {
+      aOverflowRect->Inflate(NSIntPixelsToAppUnits(2, p2a));
+      return true;
+    }
+  }
+
+  return false;
+}
+
+static const int32_t kRegularScrollbarThumbMinSize = 26;
+static const int32_t kSmallScrollbarThumbMinSize = 26;
+
+NS_IMETHODIMP
+nsNativeThemeCocoa::GetMinimumWidgetSize(nsPresContext* aPresContext,
+                                         nsIFrame* aFrame,
+                                         uint8_t aWidgetType,
+                                         LayoutDeviceIntSize* aResult,
+                                         bool* aIsOverridable)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  aResult->SizeTo(0,0);
+  *aIsOverridable = true;
+
+  switch (aWidgetType) {
+    case NS_THEME_BUTTON:
+    {
+      aResult->SizeTo(pushButtonSettings.minimumSizes[miniControlSize].width,
+                      pushButtonSettings.naturalSizes[miniControlSize].height);
+      break;
+    }
+
+    case NS_THEME_BUTTON_ARROW_UP:
+    case NS_THEME_BUTTON_ARROW_DOWN:
+    {
+      aResult->SizeTo(kMenuScrollArrowSize.width, kMenuScrollArrowSize.height);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_MENUARROW:
+    {
+      aResult->SizeTo(kMenuarrowSize.width, kMenuarrowSize.height);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_OPEN:
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_CLOSED:
+    {
+      aResult->SizeTo(kDisclosureButtonSize.width, kDisclosureButtonSize.height);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_MAC_HELP_BUTTON:
+    {
+      aResult->SizeTo(kHelpButtonSize.width, kHelpButtonSize.height);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_TOOLBARBUTTON:
+    {
+      aResult->SizeTo(0, toolbarButtonHeights[miniControlSize]);
+      break;
+    }
+
+    case NS_THEME_SPINNER:
+    case NS_THEME_SPINNER_UPBUTTON:
+    case NS_THEME_SPINNER_DOWNBUTTON:
+    {
+      SInt32 buttonHeight = 0, buttonWidth = 0;
+      if (aFrame->GetContent()->IsXULElement()) {
+        ::GetThemeMetric(kThemeMetricLittleArrowsWidth, &buttonWidth);
+        ::GetThemeMetric(kThemeMetricLittleArrowsHeight, &buttonHeight);
+      } else {
+        NSSize size =
+          spinnerSettings.minimumSizes[EnumSizeForCocoaSize(NSMiniControlSize)];
+        buttonWidth = size.width;
+        buttonHeight = size.height;
+        if (aWidgetType != NS_THEME_SPINNER) {
+          // the buttons are half the height of the spinner
+          buttonHeight /= 2;
+        }
+      }
+      aResult->SizeTo(buttonWidth, buttonHeight);
+      *aIsOverridable = true;
+      break;
+    }
+
+    case NS_THEME_MENULIST:
+    case NS_THEME_MENULIST_BUTTON:
+    {
+      SInt32 popupHeight = 0;
+      ::GetThemeMetric(kThemeMetricPopupButtonHeight, &popupHeight);
+      aResult->SizeTo(0, popupHeight);
+      break;
+    }
+
+    case NS_THEME_NUMBER_INPUT:
+    case NS_THEME_TEXTFIELD:
+    case NS_THEME_TEXTFIELD_MULTILINE:
+    case NS_THEME_SEARCHFIELD:
+    {
+      // at minimum, we should be tall enough for 9pt text.
+      // I'm using hardcoded values here because the appearance manager
+      // values for the frame size are incorrect.
+      aResult->SizeTo(0, (2 + 2) /* top */ + 9 + (1 + 1) /* bottom */);
+      break;
+    }
+
+    case NS_THEME_WINDOW_BUTTON_BOX: {
+      NSSize size = WindowButtonsSize(aFrame);
+      aResult->SizeTo(size.width, size.height);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_MAC_FULLSCREEN_BUTTON: {
+      if ([NativeWindowForFrame(aFrame) respondsToSelector:@selector(toggleFullScreen:)] &&
+          !nsCocoaFeatures::OnYosemiteOrLater()) {
+        // This value is hardcoded because it's needed before we can measure the
+        // position and size of the fullscreen button.
+        aResult->SizeTo(16, 17);
+      }
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_PROGRESSBAR:
+    {
+      SInt32 barHeight = 0;
+      ::GetThemeMetric(kThemeMetricNormalProgressBarThickness, &barHeight);
+      aResult->SizeTo(0, barHeight);
+      break;
+    }
+
+    case NS_THEME_TREETWISTY:
+    case NS_THEME_TREETWISTYOPEN:   
+    {
+      SInt32 twistyHeight = 0, twistyWidth = 0;
+      ::GetThemeMetric(kThemeMetricDisclosureButtonWidth, &twistyWidth);
+      ::GetThemeMetric(kThemeMetricDisclosureButtonHeight, &twistyHeight);
+      aResult->SizeTo(twistyWidth, twistyHeight);
+      *aIsOverridable = false;
+      break;
+    }
+    
+    case NS_THEME_TREEHEADER:
+    case NS_THEME_TREEHEADERCELL:
+    {
+      SInt32 headerHeight = 0;
+      ::GetThemeMetric(kThemeMetricListHeaderHeight, &headerHeight);
+      aResult->SizeTo(0, headerHeight - 1); // We don't need the top border.
+      break;
+    }
+
+    case NS_THEME_TAB:
+    {
+      aResult->SizeTo(0, tabHeights[miniControlSize]);
+      break;
+    }
+
+    case NS_THEME_RANGE:
+    {
+      // The Mac Appearance Manager API (the old API we're currently using)
+      // doesn't define constants to obtain a minimum size for sliders. We use
+      // the "thickness" of a slider that has default dimensions for both the
+      // minimum width and height to get something sane and so that paint
+      // invalidation works.
+      SInt32 size = 0;
+      if (IsRangeHorizontal(aFrame)) {
+        ::GetThemeMetric(kThemeMetricHSliderHeight, &size);
+      } else {
+        ::GetThemeMetric(kThemeMetricVSliderWidth, &size);
+      }
+      aResult->SizeTo(size, size);
+      *aIsOverridable = true;
+      break;
+    }
+
+    case NS_THEME_RANGE_THUMB:
+    {
+      SInt32 width = 0;
+      SInt32 height = 0;
+      ::GetThemeMetric(kThemeMetricSliderMinThumbWidth, &width);
+      ::GetThemeMetric(kThemeMetricSliderMinThumbHeight, &height);
+      aResult->SizeTo(width, height);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_SCALE_HORIZONTAL:
+    {
+      SInt32 scaleHeight = 0;
+      ::GetThemeMetric(kThemeMetricHSliderHeight, &scaleHeight);
+      aResult->SizeTo(scaleHeight, scaleHeight);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_SCALE_VERTICAL:
+    {
+      SInt32 scaleWidth = 0;
+      ::GetThemeMetric(kThemeMetricVSliderWidth, &scaleWidth);
+      aResult->SizeTo(scaleWidth, scaleWidth);
+      *aIsOverridable = false;
+      break;
+    }
+
+    case NS_THEME_SCROLLBARTHUMB_HORIZONTAL:
+    case NS_THEME_SCROLLBARTHUMB_VERTICAL:
+    {
+      // Find our parent scrollbar frame in order to find out whether we're in
+      // a small or a large scrollbar.
+      nsIFrame *scrollbarFrame = GetParentScrollbarFrame(aFrame);
+      if (!scrollbarFrame) {
+        return NS_ERROR_FAILURE;
+      }
+      
+      bool isSmall = (scrollbarFrame->StyleDisplay()->mAppearance == NS_THEME_SCROLLBAR_SMALL);
+      bool isHorizontal = (aWidgetType == NS_THEME_SCROLLBARTHUMB_HORIZONTAL);
+      int32_t& minSize = isHorizontal ? aResult->width : aResult->height;
+      minSize = isSmall ? kSmallScrollbarThumbMinSize : kRegularScrollbarThumbMinSize;
+      break;
+    }
+
+    case NS_THEME_SCROLLBAR:
+    case NS_THEME_SCROLLBAR_SMALL:
+    case NS_THEME_SCROLLBARTRACK_VERTICAL:
+    case NS_THEME_SCROLLBARTRACK_HORIZONTAL:
+    {
+      *aIsOverridable = false;
+
+      if (nsLookAndFeel::UseOverlayScrollbars()) {
+        nsIFrame* scrollbarFrame = GetParentScrollbarFrame(aFrame);
+        if (scrollbarFrame &&
+            scrollbarFrame->StyleDisplay()->mAppearance ==
+              NS_THEME_SCROLLBAR_SMALL) {
+          aResult->SizeTo(14, 14);
+        }
+        else {
+          aResult->SizeTo(16, 16);
+        }
+        if (IsScrollbarWidthThin(aFrame)) {
+          aResult->SizeTo(8, 8);
+        }
+        break;
+      }
+
+      // yeah, i know i'm cheating a little here, but i figure that it
+      // really doesn't matter if the scrollbar is vertical or horizontal
+      // and the width metric is a really good metric for every piece
+      // of the scrollbar.
+
+      nsIFrame *scrollbarFrame = GetParentScrollbarFrame(aFrame);
+      if (!scrollbarFrame) return NS_ERROR_FAILURE;
+
+      int32_t themeMetric = (scrollbarFrame->StyleDisplay()->mAppearance == NS_THEME_SCROLLBAR_SMALL) ?
+                            kThemeMetricSmallScrollBarWidth :
+                            kThemeMetricScrollBarWidth;
+      SInt32 scrollbarWidth = 0;
+      ::GetThemeMetric(themeMetric, &scrollbarWidth);
+      if (IsScrollbarWidthThin(aFrame)) {
+        scrollbarWidth /= 2;
+      }
+      aResult->SizeTo(scrollbarWidth, scrollbarWidth);
+      break;
+    }
+
+    case NS_THEME_SCROLLBAR_NON_DISAPPEARING:
+    {
+      int32_t themeMetric = kThemeMetricScrollBarWidth;
+
+      if (aFrame) {
+        nsIFrame* scrollbarFrame = GetParentScrollbarFrame(aFrame);
+        if (scrollbarFrame &&
+            scrollbarFrame->StyleDisplay()->mAppearance ==
+            NS_THEME_SCROLLBAR_SMALL) {
+          // XXX We're interested in the width of non-disappearing scrollbars
+          // to leave enough space for a dropmarker in non-native styled
+          // comboboxes (bug 869314). It isn't clear to me if comboboxes can
+          // ever have small scrollbars.
+          themeMetric = kThemeMetricSmallScrollBarWidth;
+        }
+      }
+
+      SInt32 scrollbarWidth = 0;
+      ::GetThemeMetric(themeMetric, &scrollbarWidth);
+      aResult->SizeTo(scrollbarWidth, scrollbarWidth);
+      break;
+    }
+
+    case NS_THEME_SCROLLBARBUTTON_UP:
+    case NS_THEME_SCROLLBARBUTTON_DOWN:
+    case NS_THEME_SCROLLBARBUTTON_LEFT:
+    case NS_THEME_SCROLLBARBUTTON_RIGHT:
+    {
+      if (!IsScrollbarWidthThin(aFrame)) {
+        // Get scrollbar button metrics from the system, except in the case of
+        // thin scrollbars, where we leave them at 0 (collapse)
+
+        nsIFrame *scrollbarFrame = GetParentScrollbarFrame(aFrame);
+        if (!scrollbarFrame) return NS_ERROR_FAILURE;
+
+        // Since there is no NS_THEME_SCROLLBARBUTTON_UP_SMALL we need to ask the parent what appearance style it has.
+        int32_t themeMetric = (scrollbarFrame->StyleDisplay()->mAppearance == NS_THEME_SCROLLBAR_SMALL) ?
+                              kThemeMetricSmallScrollBarWidth :
+                              kThemeMetricScrollBarWidth;
+        SInt32 scrollbarWidth = 0;
+        ::GetThemeMetric(themeMetric, &scrollbarWidth);
+
+        // It seems that for both sizes of scrollbar, the buttons are one pixel "longer".
+        if (aWidgetType == NS_THEME_SCROLLBARBUTTON_LEFT || aWidgetType == NS_THEME_SCROLLBARBUTTON_RIGHT)
+          aResult->SizeTo(scrollbarWidth+1, scrollbarWidth);
+        else
+          aResult->SizeTo(scrollbarWidth, scrollbarWidth+1);
+      }
+      *aIsOverridable = false;
+      break;
+    }
+    case NS_THEME_RESIZER:
+    {
+      HIThemeGrowBoxDrawInfo drawInfo;
+      drawInfo.version = 0;
+      drawInfo.state = kThemeStateActive;
+      drawInfo.kind = kHIThemeGrowBoxKindNormal;
+      drawInfo.direction = kThemeGrowRight | kThemeGrowDown;
+      drawInfo.size = kHIThemeGrowBoxSizeNormal;
+      HIPoint pnt = { 0, 0 };
+      HIRect bounds;
+      HIThemeGetGrowBoxBounds(&pnt, &drawInfo, &bounds);
+      aResult->SizeTo(bounds.size.width, bounds.size.height);
+      *aIsOverridable = false;
+    }
+  }
+
+  if (IsHiDPIContext(aPresContext)) {
+    *aResult = *aResult * 2;
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsNativeThemeCocoa::WidgetStateChanged(nsIFrame* aFrame, uint8_t aWidgetType, 
+                                       nsIAtom* aAttribute, bool* aShouldRepaint,
+                                       const nsAttrValue* aOldValue)
+{
+  // Some widget types just never change state.
+  switch (aWidgetType) {
+    case NS_THEME_WINDOW_TITLEBAR:
+    case NS_THEME_TOOLBOX:
+    case NS_THEME_TOOLBAR:
+    case NS_THEME_STATUSBAR:
+    case NS_THEME_STATUSBARPANEL:
+    case NS_THEME_RESIZERPANEL:
+    case NS_THEME_TOOLTIP:
+    case NS_THEME_TABPANELS:
+    case NS_THEME_TABPANEL:
+    case NS_THEME_DIALOG:
+    case NS_THEME_MENUPOPUP:
+    case NS_THEME_GROUPBOX:
+    case NS_THEME_PROGRESSCHUNK:
+    case NS_THEME_PROGRESSCHUNK_VERTICAL:
+    case NS_THEME_PROGRESSBAR:
+    case NS_THEME_PROGRESSBAR_VERTICAL:
+    case NS_THEME_METERBAR:
+    case NS_THEME_METERCHUNK:
+    case NS_THEME_MAC_VIBRANCY_LIGHT:
+    case NS_THEME_MAC_VIBRANCY_DARK:
+      *aShouldRepaint = false;
+      return NS_OK;
+  }
+
+  // XXXdwh Not sure what can really be done here.  Can at least guess for
+  // specific widgets that they're highly unlikely to have certain states.
+  // For example, a toolbar doesn't care about any states.
+  if (!aAttribute) {
+    // Hover/focus/active changed.  Always repaint.
+    *aShouldRepaint = true;
+  } else {
+    // Check the attribute to see if it's relevant.  
+    // disabled, checked, dlgtype, default, etc.
+    *aShouldRepaint = false;
+    if (aAttribute == nsGkAtoms::disabled ||
+        aAttribute == nsGkAtoms::checked ||
+        aAttribute == nsGkAtoms::selected ||
+        aAttribute == nsGkAtoms::visuallyselected ||
+        aAttribute == nsGkAtoms::menuactive ||
+        aAttribute == nsGkAtoms::sortDirection ||
+        aAttribute == nsGkAtoms::focused ||
+        aAttribute == nsGkAtoms::_default ||
+        aAttribute == nsGkAtoms::open ||
+        aAttribute == nsGkAtoms::hover)
+      *aShouldRepaint = true;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsNativeThemeCocoa::ThemeChanged()
+{
+  // This is unimplemented because we don't care if gecko changes its theme
+  // and Mac OS X doesn't have themes.
+  return NS_OK;
+}
+
+bool 
+nsNativeThemeCocoa::ThemeSupportsWidget(nsPresContext* aPresContext, nsIFrame* aFrame,
+                                      uint8_t aWidgetType)
+{
+  // We don't have CSS set up to render non-native scrollbars on Mac OS X so we
+  // render natively even if native theme support is disabled.
+  if (aWidgetType != NS_THEME_SCROLLBAR &&
+      aPresContext && !aPresContext->PresShell()->IsThemeSupportEnabled())
+    return false;
+
+  // if this is a dropdown button in a combobox the answer is always no
+  if (aWidgetType == NS_THEME_MENULIST_BUTTON) {
+    nsIFrame* parentFrame = aFrame->GetParent();
+    if (parentFrame && (parentFrame->GetType() == nsGkAtoms::comboboxControlFrame))
+      return false;
+  }
+
+  switch (aWidgetType) {
+    // Combobox dropdowns don't support native theming in vertical mode.
+    case NS_THEME_MENULIST:
+    case NS_THEME_MENULIST_BUTTON:
+    case NS_THEME_MENULIST_TEXT:
+    case NS_THEME_MENULIST_TEXTFIELD:
+      if (aFrame && aFrame->GetWritingMode().IsVertical()) {
+        return false;
+      }
+      MOZ_FALLTHROUGH;
+
+    case NS_THEME_LISTBOX:
+
+    case NS_THEME_DIALOG:
+    case NS_THEME_WINDOW:
+    case NS_THEME_WINDOW_BUTTON_BOX:
+    case NS_THEME_WINDOW_TITLEBAR:
+    case NS_THEME_CHECKMENUITEM:
+    case NS_THEME_MENUPOPUP:
+    case NS_THEME_MENUARROW:
+    case NS_THEME_MENUITEM:
+    case NS_THEME_MENUSEPARATOR:
+    case NS_THEME_MAC_FULLSCREEN_BUTTON:
+    case NS_THEME_TOOLTIP:
+    
+    case NS_THEME_CHECKBOX:
+    case NS_THEME_CHECKBOX_CONTAINER:
+    case NS_THEME_RADIO:
+    case NS_THEME_RADIO_CONTAINER:
+    case NS_THEME_GROUPBOX:
+    case NS_THEME_MAC_HELP_BUTTON:
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_OPEN:
+    case NS_THEME_MAC_DISCLOSURE_BUTTON_CLOSED:
+    case NS_THEME_BUTTON:
+    case NS_THEME_BUTTON_ARROW_UP:
+    case NS_THEME_BUTTON_ARROW_DOWN:
+    case NS_THEME_BUTTON_BEVEL:
+    case NS_THEME_TOOLBARBUTTON:
+    case NS_THEME_SPINNER:
+    case NS_THEME_SPINNER_UPBUTTON:
+    case NS_THEME_SPINNER_DOWNBUTTON:
+    case NS_THEME_TOOLBAR:
+    case NS_THEME_STATUSBAR:
+    case NS_THEME_NUMBER_INPUT:
+    case NS_THEME_TEXTFIELD:
+    case NS_THEME_TEXTFIELD_MULTILINE:
+    case NS_THEME_SEARCHFIELD:
+    case NS_THEME_TOOLBOX:
+    //case NS_THEME_TOOLBARBUTTON:
+    case NS_THEME_PROGRESSBAR:
+    case NS_THEME_PROGRESSBAR_VERTICAL:
+    case NS_THEME_PROGRESSCHUNK:
+    case NS_THEME_PROGRESSCHUNK_VERTICAL:
+    case NS_THEME_METERBAR:
+    case NS_THEME_METERCHUNK:
+    case NS_THEME_SEPARATOR:
+    
+    case NS_THEME_TABPANELS:
+    case NS_THEME_TAB:
+    
+    case NS_THEME_TREETWISTY:
+    case NS_THEME_TREETWISTYOPEN:
+    case NS_THEME_TREEVIEW:
+    case NS_THEME_TREEHEADER:
+    case NS_THEME_TREEHEADERCELL:
+    case NS_THEME_TREEHEADERSORTARROW:
+    case NS_THEME_TREEITEM:
+    case NS_THEME_TREELINE:
+    case NS_THEME_MAC_SOURCE_LIST:
+    case NS_THEME_MAC_SOURCE_LIST_SELECTION:
+    case NS_THEME_MAC_ACTIVE_SOURCE_LIST_SELECTION:
+
+    case NS_THEME_RANGE:
+
+    case NS_THEME_SCALE_HORIZONTAL:
+    case NS_THEME_SCALETHUMB_HORIZONTAL:
+    case NS_THEME_SCALE_VERTICAL:
+    case NS_THEME_SCALETHUMB_VERTICAL:
+
+    case NS_THEME_SCROLLBAR:
+    case NS_THEME_SCROLLBAR_SMALL:
+    case NS_THEME_SCROLLBARBUTTON_UP:
+    case NS_THEME_SCROLLBARBUTTON_DOWN:
+    case NS_THEME_SCROLLBARBUTTON_LEFT:
+    case NS_THEME_SCROLLBARBUTTON_RIGHT:
+    case NS_THEME_SCROLLBARTHUMB_HORIZONTAL:
+    case NS_THEME_SCROLLBARTHUMB_VERTICAL:
+    case NS_THEME_SCROLLBARTRACK_VERTICAL:
+    case NS_THEME_SCROLLBARTRACK_HORIZONTAL:
+    case NS_THEME_SCROLLBAR_NON_DISAPPEARING:
+      return !IsWidgetStyled(aPresContext, aFrame, aWidgetType);
+
+    case NS_THEME_RESIZER:
+    {
+      nsIFrame* parentFrame = aFrame->GetParent();
+      if (!parentFrame || parentFrame->GetType() != nsGkAtoms::scrollFrame)
+        return true;
+
+      // Note that IsWidgetStyled is not called for resizers on Mac. This is
+      // because for scrollable containers, the native resizer looks better
+      // when (non-overlay) scrollbars are present even when the style is
+      // overriden, and the custom transparent resizer looks better when
+      // scrollbars are not present.
+      nsIScrollableFrame* scrollFrame = do_QueryFrame(parentFrame);
+      return (!nsLookAndFeel::UseOverlayScrollbars() &&
+              scrollFrame && scrollFrame->GetScrollbarVisibility());
+    }
+
+    case NS_THEME_FOCUS_OUTLINE:
+      return true;
+
+    case NS_THEME_MAC_VIBRANCY_LIGHT:
+    case NS_THEME_MAC_VIBRANCY_DARK:
+      return VibrancyManager::SystemSupportsVibrancy();
+  }
+
+  return false;
+}
+
+bool
+nsNativeThemeCocoa::WidgetIsContainer(uint8_t aWidgetType)
+{
+  // flesh this out at some point
+  switch (aWidgetType) {
+   case NS_THEME_MENULIST_BUTTON:
+   case NS_THEME_RADIO:
+   case NS_THEME_CHECKBOX:
+   case NS_THEME_PROGRESSBAR:
+   case NS_THEME_METERBAR:
+   case NS_THEME_RANGE:
+   case NS_THEME_MAC_HELP_BUTTON:
+   case NS_THEME_MAC_DISCLOSURE_BUTTON_OPEN:
+   case NS_THEME_MAC_DISCLOSURE_BUTTON_CLOSED:
+    return false;
+  }
+  return true;
+}
+
+bool
+nsNativeThemeCocoa::ThemeDrawsFocusForWidget(uint8_t aWidgetType)
+{
+  if (aWidgetType == NS_THEME_MENULIST ||
+      aWidgetType == NS_THEME_MENULIST_TEXTFIELD ||
+      aWidgetType == NS_THEME_BUTTON ||
+      aWidgetType == NS_THEME_MAC_HELP_BUTTON ||
+      aWidgetType == NS_THEME_MAC_DISCLOSURE_BUTTON_OPEN ||
+      aWidgetType == NS_THEME_MAC_DISCLOSURE_BUTTON_CLOSED ||
+      aWidgetType == NS_THEME_RADIO ||
+      aWidgetType == NS_THEME_RANGE ||
+      aWidgetType == NS_THEME_CHECKBOX)
+    return true;
+
+  return false;
+}
+
+bool
+nsNativeThemeCocoa::ThemeNeedsComboboxDropmarker()
+{
+  return false;
+}
+
+bool
+nsNativeThemeCocoa::WidgetAppearanceDependsOnWindowFocus(uint8_t aWidgetType)
+{
+  switch (aWidgetType) {
+    case NS_THEME_DIALOG:
+    case NS_THEME_GROUPBOX:
+    case NS_THEME_TABPANELS:
+    case NS_THEME_BUTTON_ARROW_UP:
+    case NS_THEME_BUTTON_ARROW_DOWN:
+    case NS_THEME_CHECKMENUITEM:
+    case NS_THEME_MENUPOPUP:
+    case NS_THEME_MENUARROW:
+    case NS_THEME_MENUITEM:
+    case NS_THEME_MENUSEPARATOR:
+    case NS_THEME_TOOLTIP:
+    case NS_THEME_SPINNER:
+    case NS_THEME_SPINNER_UPBUTTON:
+    case NS_THEME_SPINNER_DOWNBUTTON:
+    case NS_THEME_SEPARATOR:
+    case NS_THEME_TOOLBOX:
+    case NS_THEME_NUMBER_INPUT:
+    case NS_THEME_TEXTFIELD:
+    case NS_THEME_TREEVIEW:
+    case NS_THEME_TREELINE:
+    case NS_THEME_TEXTFIELD_MULTILINE:
+    case NS_THEME_LISTBOX:
+    case NS_THEME_RESIZER:
+      return false;
+    default:
+      return true;
+  }
+}
+
+bool
+nsNativeThemeCocoa::IsWindowSheet(nsIFrame* aFrame)
+{
+  NSWindow* win = NativeWindowForFrame(aFrame);
+  id winDelegate = [win delegate];
+  nsIWidget* widget = [(WindowDelegate *)winDelegate geckoWidget];
+  if (!widget) {
+    return false;
+  }
+  return (widget->WindowType() == eWindowType_sheet);
+}
+
+bool
+nsNativeThemeCocoa::NeedToClearBackgroundBehindWidget(nsIFrame* aFrame,
+                                                      uint8_t aWidgetType)
+{
+  switch (aWidgetType) {
+    case NS_THEME_MAC_SOURCE_LIST:
+    // If we're in a XUL tree, we don't want to clear the background behind the
+    // selections below, since that would make our source list to not pick up
+    // the right font smoothing background. But since we don't call this method
+    // in nsTreeBodyFrame::BuildDisplayList, we never get here.
+    case NS_THEME_MAC_SOURCE_LIST_SELECTION:
+    case NS_THEME_MAC_ACTIVE_SOURCE_LIST_SELECTION:
+    case NS_THEME_MAC_VIBRANCY_LIGHT:
+    case NS_THEME_MAC_VIBRANCY_DARK:
+    case NS_THEME_TOOLTIP:
+    case NS_THEME_MENUPOPUP:
+    case NS_THEME_MENUITEM:
+    case NS_THEME_CHECKMENUITEM:
+      return true;
+    case NS_THEME_DIALOG:
+      return IsWindowSheet(aFrame);
+    default:
+      return false;
+  }
+}
+
+static nscolor ConvertNSColor(NSColor* aColor)
+{
+  NSColor* deviceColor = [aColor colorUsingColorSpaceName:NSDeviceRGBColorSpace];
+  return NS_RGBA((unsigned int)([deviceColor redComponent] * 255.0),
+                 (unsigned int)([deviceColor greenComponent] * 255.0),
+                 (unsigned int)([deviceColor blueComponent] * 255.0),
+                 (unsigned int)([deviceColor alphaComponent] * 255.0));
+}
+
+bool
+nsNativeThemeCocoa::WidgetProvidesFontSmoothingBackgroundColor(nsIFrame* aFrame,
+                                                               uint8_t aWidgetType,
+                                                               nscolor* aColor)
+{
+  switch (aWidgetType) {
+    case NS_THEME_MAC_SOURCE_LIST:
+    case NS_THEME_MAC_SOURCE_LIST_SELECTION:
+    case NS_THEME_MAC_ACTIVE_SOURCE_LIST_SELECTION:
+    case NS_THEME_MAC_VIBRANCY_LIGHT:
+    case NS_THEME_MAC_VIBRANCY_DARK:
+    case NS_THEME_TOOLTIP:
+    case NS_THEME_MENUPOPUP:
+    case NS_THEME_MENUITEM:
+    case NS_THEME_CHECKMENUITEM:
+    case NS_THEME_DIALOG:
+    {
+      if ((aWidgetType == NS_THEME_DIALOG && !IsWindowSheet(aFrame)) ||
+          ((aWidgetType == NS_THEME_MAC_SOURCE_LIST_SELECTION ||
+            aWidgetType == NS_THEME_MAC_ACTIVE_SOURCE_LIST_SELECTION) &&
+            !IsInSourceList(aFrame))) {
+        return false;
+      }
+      ChildView* childView = ChildViewForFrame(aFrame);
+      if (childView) {
+        ThemeGeometryType type = ThemeGeometryTypeForWidget(aFrame, aWidgetType);
+        NSColor* color = [childView vibrancyFontSmoothingBackgroundColorForThemeGeometryType:type];
+        *aColor = ConvertNSColor(color);
+        return true;
+      }
+      return false;
+    }
+    default:
+      return false;
+  }
+}
+
+nsITheme::ThemeGeometryType
+nsNativeThemeCocoa::ThemeGeometryTypeForWidget(nsIFrame* aFrame, uint8_t aWidgetType)
+{
+  switch (aWidgetType) {
+    case NS_THEME_WINDOW_TITLEBAR:
+      return eThemeGeometryTypeTitlebar;
+    case NS_THEME_TOOLBAR:
+      return eThemeGeometryTypeToolbar;
+    case NS_THEME_TOOLBOX:
+      return eThemeGeometryTypeToolbox;
+    case NS_THEME_WINDOW_BUTTON_BOX:
+      return eThemeGeometryTypeWindowButtons;
+    case NS_THEME_MAC_FULLSCREEN_BUTTON:
+      return eThemeGeometryTypeFullscreenButton;
+    case NS_THEME_MAC_VIBRANCY_LIGHT:
+      return eThemeGeometryTypeVibrancyLight;
+    case NS_THEME_MAC_VIBRANCY_DARK:
+      return eThemeGeometryTypeVibrancyDark;
+    case NS_THEME_TOOLTIP:
+      return eThemeGeometryTypeTooltip;
+    case NS_THEME_MENUPOPUP:
+      return eThemeGeometryTypeMenu;
+    case NS_THEME_MENUITEM:
+    case NS_THEME_CHECKMENUITEM: {
+      EventStates eventState = GetContentState(aFrame, aWidgetType);
+      bool isDisabled = IsDisabled(aFrame, eventState);
+      bool isSelected = !isDisabled && CheckBooleanAttr(aFrame, nsGkAtoms::menuactive);
+      return isSelected ? eThemeGeometryTypeHighlightedMenuItem : eThemeGeometryTypeMenu;
+    }
+    case NS_THEME_DIALOG:
+      return IsWindowSheet(aFrame) ? eThemeGeometryTypeSheet : eThemeGeometryTypeUnknown;
+    case NS_THEME_MAC_SOURCE_LIST:
+      return eThemeGeometryTypeSourceList;
+    case NS_THEME_MAC_SOURCE_LIST_SELECTION:
+      return IsInSourceList(aFrame) ? eThemeGeometryTypeSourceListSelection
+                                    : eThemeGeometryTypeUnknown;
+    case NS_THEME_MAC_ACTIVE_SOURCE_LIST_SELECTION:
+      return IsInSourceList(aFrame) ? eThemeGeometryTypeActiveSourceListSelection
+                                    : eThemeGeometryTypeUnknown;
+    default:
+      return eThemeGeometryTypeUnknown;
+  }
+}
+
+nsITheme::Transparency
+nsNativeThemeCocoa::GetWidgetTransparency(nsIFrame* aFrame, uint8_t aWidgetType)
+{
+  switch (aWidgetType) {
+  case NS_THEME_MENUPOPUP:
+  case NS_THEME_TOOLTIP:
+    return eTransparent;
+
+  case NS_THEME_DIALOG:
+    return IsWindowSheet(aFrame) ? eTransparent : eOpaque;
+
+  case NS_THEME_SCROLLBAR_SMALL:
+  case NS_THEME_SCROLLBAR:
+    return nsLookAndFeel::UseOverlayScrollbars() ? eTransparent : eOpaque;
+
+  case NS_THEME_STATUSBAR:
+    // Knowing that scrollbars and statusbars are opaque improves
+    // performance, because we create layers for them.
+    return eOpaque;
+
+  case NS_THEME_TOOLBAR:
+    return eOpaque;
+
+  default:
+    return eUnknownTransparency;
+  }
+}
diff --git a/widget/cocoa/nsNativeThemeColors.h b/widget/cocoa/nsNativeThemeColors.h
new file mode 100644
index 0000000000..b1691b5163
--- /dev/null
+++ b/widget/cocoa/nsNativeThemeColors.h
@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsNativeThemeColors_h_
+#define nsNativeThemeColors_h_
+
+#include "nsCocoaFeatures.h"
+#import <Cocoa/Cocoa.h>
+
+enum ColorName {
+  toolbarTopBorderGrey,
+  toolbarFillGrey,
+  toolbarBottomBorderGrey,
+};
+
+static const int sLionThemeColors[][2] = {
+  /* { active window, inactive window } */
+  // toolbar:
+  { 0xD0, 0xF0 }, // top separator line
+  { 0xB2, 0xE1 }, // fill color
+  { 0x59, 0x87 }, // bottom separator line
+};
+
+static const int sYosemiteThemeColors[][2] = {
+  /* { active window, inactive window } */
+  // toolbar:
+  { 0xBD, 0xDF }, // top separator line
+  { 0xD3, 0xF6 }, // fill color
+  { 0xB3, 0xD1 }, // bottom separator line
+};
+
+__attribute__((unused))
+static int NativeGreyColorAsInt(ColorName name, BOOL isMain)
+{
+  if (nsCocoaFeatures::OnYosemiteOrLater())
+    return sYosemiteThemeColors[name][isMain ? 0 : 1];
+  return sLionThemeColors[name][isMain ? 0 : 1];
+}
+
+__attribute__((unused))
+static float NativeGreyColorAsFloat(ColorName name, BOOL isMain)
+{
+  return NativeGreyColorAsInt(name, isMain) / 255.0f;
+}
+
+__attribute__((unused))
+static void DrawNativeGreyColorInRect(CGContextRef context, ColorName name,
+                                      CGRect rect, BOOL isMain)
+{
+  float grey = NativeGreyColorAsFloat(name, isMain);
+  CGContextSetRGBFillColor(context, grey, grey, grey, 1.0f);
+  CGContextFillRect(context, rect);
+}
+
+#endif // nsNativeThemeColors_h_
diff --git a/widget/cocoa/nsPIWidgetCocoa.idl b/widget/cocoa/nsPIWidgetCocoa.idl
new file mode 100644
index 0000000000..a8fd8149ce
--- /dev/null
+++ b/widget/cocoa/nsPIWidgetCocoa.idl
@@ -0,0 +1,37 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIWidget;
+
+[ptr] native NSWindowPtr(NSWindow);
+
+//
+// nsPIWidgetCocoa
+//
+// A private interface (unfrozen, private to the widget implementation) that
+// gives us access to some extra features on a widget/window.
+//
+[uuid(f75ff69e-3a51-419e-bd29-042f804bc2ed)]
+interface nsPIWidgetCocoa : nsISupports
+{
+  void SendSetZLevelEvent();
+
+  // Find the displayed child sheet (if aShown) or a child sheet that
+  // wants to be displayed (if !aShown)
+  nsIWidget GetChildSheet(in boolean aShown);
+  
+  // Get the parent widget (if any) StandardCreate() was called with.
+  nsIWidget GetRealParent();
+  
+  // If the object implementing this interface is a sheet, this will return the
+  // native NSWindow it is attached to
+  readonly attribute NSWindowPtr sheetWindowParent;
+
+  // True if window is a sheet
+  readonly attribute boolean isSheet;
+  
+}; // nsPIWidgetCocoa
diff --git a/widget/cocoa/nsPrintDialogX.h b/widget/cocoa/nsPrintDialogX.h
new file mode 100644
index 0000000000..470f17d99d
--- /dev/null
+++ b/widget/cocoa/nsPrintDialogX.h
@@ -0,0 +1,68 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsPrintDialog_h_
+#define nsPrintDialog_h_
+
+#include "nsIPrintDialogService.h"
+#include "nsCOMPtr.h"
+#include "nsCocoaUtils.h"
+
+#import <Cocoa/Cocoa.h>
+
+class nsIPrintSettings;
+class nsIStringBundle;
+
+class nsPrintDialogServiceX : public nsIPrintDialogService
+{
+public:
+  nsPrintDialogServiceX();
+
+  NS_DECL_ISUPPORTS
+
+  NS_IMETHOD Init() override;
+  NS_IMETHOD Show(nsPIDOMWindowOuter *aParent, nsIPrintSettings *aSettings,
+                  nsIWebBrowserPrint *aWebBrowserPrint) override;
+  NS_IMETHOD ShowPageSetup(nsPIDOMWindowOuter *aParent,
+                           nsIPrintSettings *aSettings) override;
+
+protected:
+  virtual ~nsPrintDialogServiceX();
+};
+
+@interface PrintPanelAccessoryView : NSView
+{
+  nsIPrintSettings* mSettings;
+  nsIStringBundle* mPrintBundle;
+  NSButton* mPrintSelectionOnlyCheckbox;
+  NSButton* mShrinkToFitCheckbox;
+  NSButton* mPrintBGColorsCheckbox;
+  NSButton* mPrintBGImagesCheckbox;
+  NSButtonCell* mAsLaidOutRadio;
+  NSButtonCell* mSelectedFrameRadio;
+  NSButtonCell* mSeparateFramesRadio;
+  NSPopUpButton* mHeaderLeftList;
+  NSPopUpButton* mHeaderCenterList;
+  NSPopUpButton* mHeaderRightList;
+  NSPopUpButton* mFooterLeftList;
+  NSPopUpButton* mFooterCenterList;
+  NSPopUpButton* mFooterRightList;
+}
+
+- (id)initWithSettings:(nsIPrintSettings*)aSettings;
+
+- (void)exportSettings;
+
+@end
+
+@interface PrintPanelAccessoryController : NSViewController <NSPrintPanelAccessorizing>
+
+- (id)initWithSettings:(nsIPrintSettings*)aSettings;
+
+- (void)exportSettings;
+
+@end
+
+#endif // nsPrintDialog_h_
diff --git a/widget/cocoa/nsPrintDialogX.mm b/widget/cocoa/nsPrintDialogX.mm
new file mode 100644
index 0000000000..a6d58d5bfb
--- /dev/null
+++ b/widget/cocoa/nsPrintDialogX.mm
@@ -0,0 +1,682 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/ArrayUtils.h"
+
+#include "nsPrintDialogX.h"
+#include "nsIPrintSettings.h"
+#include "nsIPrintSettingsService.h"
+#include "nsPrintSettingsX.h"
+#include "nsCOMPtr.h"
+#include "nsQueryObject.h"
+#include "nsServiceManagerUtils.h"
+#include "nsIWebProgressListener.h"
+#include "nsIStringBundle.h"
+#include "nsIWebBrowserPrint.h"
+#include "nsCRT.h"
+
+#import <Cocoa/Cocoa.h>
+#include "nsObjCExceptions.h"
+
+using namespace mozilla;
+
+NS_IMPL_ISUPPORTS(nsPrintDialogServiceX, nsIPrintDialogService)
+
+nsPrintDialogServiceX::nsPrintDialogServiceX()
+{
+}
+
+nsPrintDialogServiceX::~nsPrintDialogServiceX()
+{
+}
+
+NS_IMETHODIMP
+nsPrintDialogServiceX::Init()
+{
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsPrintDialogServiceX::Show(nsPIDOMWindowOuter *aParent, nsIPrintSettings *aSettings,
+                            nsIWebBrowserPrint *aWebBrowserPrint)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NS_PRECONDITION(aSettings, "aSettings must not be null");
+
+  RefPtr<nsPrintSettingsX> settingsX(do_QueryObject(aSettings));
+  if (!settingsX)
+    return NS_ERROR_FAILURE;
+
+  nsCOMPtr<nsIPrintSettingsService> printSettingsSvc
+    = do_GetService("@mozilla.org/gfx/printsettings-service;1");
+
+  // Set the print job title
+  char16_t** docTitles;
+  uint32_t titleCount;
+  nsresult rv = aWebBrowserPrint->EnumerateDocumentNames(&titleCount, &docTitles);
+  if (NS_SUCCEEDED(rv) && titleCount > 0) {
+    CFStringRef cfTitleString = CFStringCreateWithCharacters(NULL, reinterpret_cast<const UniChar*>(docTitles[0]),
+                                                             NS_strlen(docTitles[0]));
+    if (cfTitleString) {
+      ::PMPrintSettingsSetJobName(settingsX->GetPMPrintSettings(), cfTitleString);
+      CFRelease(cfTitleString);
+    }
+    for (int32_t i = titleCount - 1; i >= 0; i--) {
+      free(docTitles[i]);
+    }
+    free(docTitles);
+    docTitles = NULL;
+    titleCount = 0;
+  }
+
+  // Read default print settings from prefs
+  printSettingsSvc->InitPrintSettingsFromPrefs(settingsX, true,
+    nsIPrintSettings::kInitSaveNativeData);
+  NSPrintInfo* printInfo = settingsX->GetCocoaPrintInfo();
+
+  // Put the print info into the current print operation, since that's where
+  // [panel runModal] will look for it. We create the view because otherwise
+  // we'll get unrelated warnings printed to the console.
+  NSView* tmpView = [[NSView alloc] init];
+  NSPrintOperation* printOperation = [NSPrintOperation printOperationWithView:tmpView printInfo:printInfo];
+  [NSPrintOperation setCurrentOperation:printOperation];
+
+  NSPrintPanel* panel = [NSPrintPanel printPanel];
+  [panel setOptions:NSPrintPanelShowsCopies
+    | NSPrintPanelShowsPageRange
+    | NSPrintPanelShowsPaperSize
+    | NSPrintPanelShowsOrientation
+    | NSPrintPanelShowsScaling ];
+  PrintPanelAccessoryController* viewController =
+    [[PrintPanelAccessoryController alloc] initWithSettings:aSettings];
+  [panel addAccessoryController:viewController];
+  [viewController release];
+
+  // Show the dialog.
+  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  int button = [panel runModal];
+  nsCocoaUtils::CleanUpAfterNativeAppModalDialog();
+
+  NSPrintInfo* copy = [[[NSPrintOperation currentOperation] printInfo] copy];
+  if (!copy) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  [NSPrintOperation setCurrentOperation:nil];
+  [tmpView release];
+
+  if (button != NSFileHandlingPanelOKButton)
+    return NS_ERROR_ABORT;
+
+  settingsX->SetCocoaPrintInfo(copy);
+  settingsX->InitUnwriteableMargin();
+
+  // Save settings unless saving is pref'd off
+  if (Preferences::GetBool("print.save_print_settings", false)) {
+    printSettingsSvc->SavePrintSettingsToPrefs(settingsX, true,
+      nsIPrintSettings::kInitSaveNativeData);
+  }
+
+  // Get coordinate space resolution for converting paper size units to inches
+  NSWindow *win = [[NSApplication sharedApplication] mainWindow];
+  if (win) {
+    NSDictionary *devDesc = [win deviceDescription];
+    if (devDesc) {
+      NSSize res = [[devDesc objectForKey: NSDeviceResolution] sizeValue];
+      float scale = [win backingScaleFactor];
+      if (scale > 0) {
+        settingsX->SetInchesScale(res.width / scale, res.height / scale);
+      }
+    }
+  }
+
+  // Export settings.
+  [viewController exportSettings];
+
+  // If "ignore scaling" is checked, overwrite scaling factor with 1.
+  bool isShrinkToFitChecked;
+  settingsX->GetShrinkToFit(&isShrinkToFitChecked);
+  if (isShrinkToFitChecked) {
+    NSMutableDictionary* dict = [copy dictionary];
+    if (dict) {
+      [dict setObject: [NSNumber numberWithFloat: 1]
+               forKey: NSPrintScalingFactor];
+    }
+    // Set the scaling factor to 100% in the NSPrintInfo
+    // object so that it will not affect the paper size
+    // retrieved from the PMPageFormat routines.
+    [copy setScalingFactor:1.0];
+  } else {
+    aSettings->SetScaling([copy scalingFactor]);
+  }
+
+  // Set the adjusted paper size now that we've updated
+  // the scaling factor.
+  settingsX->InitAdjustedPaperSize();
+
+  [copy release];
+
+  int16_t pageRange;
+  aSettings->GetPrintRange(&pageRange);
+  if (pageRange != nsIPrintSettings::kRangeSelection) {
+    PMPrintSettings nativePrintSettings = settingsX->GetPMPrintSettings();
+    UInt32 firstPage, lastPage;
+    OSStatus status = ::PMGetFirstPage(nativePrintSettings, &firstPage);
+    if (status == noErr) {
+      status = ::PMGetLastPage(nativePrintSettings, &lastPage);
+      if (status == noErr && lastPage != UINT32_MAX) {
+        aSettings->SetPrintRange(nsIPrintSettings::kRangeSpecifiedPageRange);
+        aSettings->SetStartPageRange(firstPage);
+        aSettings->SetEndPageRange(lastPage);
+      }
+    }
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsPrintDialogServiceX::ShowPageSetup(nsPIDOMWindowOuter *aParent,
+                                     nsIPrintSettings *aNSSettings)
+{
+  NS_PRECONDITION(aParent, "aParent must not be null");
+  NS_PRECONDITION(aNSSettings, "aSettings must not be null");
+  NS_ENSURE_TRUE(aNSSettings, NS_ERROR_FAILURE);
+
+  RefPtr<nsPrintSettingsX> settingsX(do_QueryObject(aNSSettings));
+  if (!settingsX)
+    return NS_ERROR_FAILURE;
+
+  NSPrintInfo* printInfo = settingsX->GetCocoaPrintInfo();
+  NSPageLayout *pageLayout = [NSPageLayout pageLayout];
+  nsCocoaUtils::PrepareForNativeAppModalDialog();
+  int button = [pageLayout runModalWithPrintInfo:printInfo];
+  nsCocoaUtils::CleanUpAfterNativeAppModalDialog();
+
+  return button == NSFileHandlingPanelOKButton ? NS_OK : NS_ERROR_ABORT;
+}
+
+// Accessory view
+
+@interface PrintPanelAccessoryView (Private)
+
+- (NSString*)localizedString:(const char*)aKey;
+
+- (int16_t)chosenFrameSetting;
+
+- (const char*)headerFooterStringForList:(NSPopUpButton*)aList;
+
+- (void)exportHeaderFooterSettings;
+
+- (void)initBundle;
+
+- (NSTextField*)label:(const char*)aLabel
+            withFrame:(NSRect)aRect
+            alignment:(NSTextAlignment)aAlignment;
+
+- (void)addLabel:(const char*)aLabel
+       withFrame:(NSRect)aRect
+       alignment:(NSTextAlignment)aAlignment;
+
+- (void)addLabel:(const char*)aLabel withFrame:(NSRect)aRect;
+
+- (void)addCenteredLabel:(const char*)aLabel withFrame:(NSRect)aRect;
+
+- (NSButton*)checkboxWithLabel:(const char*)aLabel andFrame:(NSRect)aRect;
+
+- (NSPopUpButton*)headerFooterItemListWithFrame:(NSRect)aRect
+                                   selectedItem:(const char16_t*)aCurrentString;
+
+- (void)addOptionsSection;
+
+- (void)addAppearanceSection;
+
+- (void)addFramesSection;
+
+- (void)addHeaderFooterSection;
+
+- (NSString*)summaryValueForCheckbox:(NSButton*)aCheckbox;
+
+- (NSString*)framesSummaryValue;
+
+- (NSString*)headerSummaryValue;
+
+- (NSString*)footerSummaryValue;
+
+@end
+
+static const char sHeaderFooterTags[][4] =  {"", "&T", "&U", "&D", "&P", "&PT"};
+
+@implementation PrintPanelAccessoryView
+
+// Public methods
+
+- (id)initWithSettings:(nsIPrintSettings*)aSettings
+{
+  [super initWithFrame:NSMakeRect(0, 0, 540, 270)];
+
+  mSettings = aSettings;
+  [self initBundle];
+  [self addOptionsSection];
+  [self addAppearanceSection];
+  [self addFramesSection];
+  [self addHeaderFooterSection];
+
+  return self;
+}
+
+- (void)exportSettings
+{
+  mSettings->SetPrintRange([mPrintSelectionOnlyCheckbox state] == NSOnState ?
+                             (int16_t)nsIPrintSettings::kRangeSelection :
+                             (int16_t)nsIPrintSettings::kRangeAllPages);
+  mSettings->SetShrinkToFit([mShrinkToFitCheckbox state] == NSOnState);
+  mSettings->SetPrintBGColors([mPrintBGColorsCheckbox state] == NSOnState);
+  mSettings->SetPrintBGImages([mPrintBGImagesCheckbox state] == NSOnState);
+  mSettings->SetPrintFrameType([self chosenFrameSetting]);
+
+  [self exportHeaderFooterSettings];
+}
+
+- (void)dealloc
+{
+  NS_IF_RELEASE(mPrintBundle);
+  [super dealloc];
+}
+
+// Localization
+
+- (void)initBundle
+{
+  nsCOMPtr<nsIStringBundleService> bundleSvc = do_GetService(NS_STRINGBUNDLE_CONTRACTID);
+  bundleSvc->CreateBundle("chrome://global/locale/printdialog.properties", &mPrintBundle);
+}
+
+- (NSString*)localizedString:(const char*)aKey
+{
+  if (!mPrintBundle)
+    return @"";
+
+  nsXPIDLString intlString;
+  mPrintBundle->GetStringFromName(NS_ConvertUTF8toUTF16(aKey).get(), getter_Copies(intlString));
+  NSMutableString* s = [NSMutableString stringWithUTF8String:NS_ConvertUTF16toUTF8(intlString).get()];
+
+  // Remove all underscores (they're used in the GTK dialog for accesskeys).
+  [s replaceOccurrencesOfString:@"_" withString:@"" options:0 range:NSMakeRange(0, [s length])];
+  return s;
+}
+
+// Widget helpers
+
+- (NSTextField*)label:(const char*)aLabel
+            withFrame:(NSRect)aRect
+            alignment:(NSTextAlignment)aAlignment
+{
+  NSTextField* label = [[[NSTextField alloc] initWithFrame:aRect] autorelease];
+  [label setStringValue:[self localizedString:aLabel]];
+  [label setEditable:NO];
+  [label setSelectable:NO];
+  [label setBezeled:NO];
+  [label setBordered:NO];
+  [label setDrawsBackground:NO];
+  [label setFont:[NSFont systemFontOfSize:[NSFont systemFontSize]]];
+  [label setAlignment:aAlignment];
+  return label;
+}
+
+- (void)addLabel:(const char*)aLabel
+       withFrame:(NSRect)aRect
+       alignment:(NSTextAlignment)aAlignment
+{
+  NSTextField* label = [self label:aLabel withFrame:aRect alignment:aAlignment];
+  [self addSubview:label];
+}
+
+- (void)addLabel:(const char*)aLabel withFrame:(NSRect)aRect
+{
+  [self addLabel:aLabel withFrame:aRect alignment:NSRightTextAlignment];
+}
+
+- (void)addCenteredLabel:(const char*)aLabel withFrame:(NSRect)aRect
+{
+  [self addLabel:aLabel withFrame:aRect alignment:NSCenterTextAlignment];
+}
+
+- (NSButton*)checkboxWithLabel:(const char*)aLabel andFrame:(NSRect)aRect
+{
+  aRect.origin.y += 4.0f;
+  NSButton* checkbox = [[[NSButton alloc] initWithFrame:aRect] autorelease];
+  [checkbox setButtonType:NSSwitchButton];
+  [checkbox setTitle:[self localizedString:aLabel]];
+  [checkbox setFont:[NSFont systemFontOfSize:[NSFont systemFontSize]]];
+  [checkbox sizeToFit];
+  return checkbox;
+}
+
+- (NSPopUpButton*)headerFooterItemListWithFrame:(NSRect)aRect
+                                   selectedItem:(const char16_t*)aCurrentString
+{
+  NSPopUpButton* list = [[[NSPopUpButton alloc] initWithFrame:aRect pullsDown:NO] autorelease];
+  [list setFont:[NSFont systemFontOfSize:[NSFont smallSystemFontSize]]];
+  [[list cell] setControlSize:NSSmallControlSize];
+  NSArray* items =
+    [NSArray arrayWithObjects:[self localizedString:"headerFooterBlank"],
+                              [self localizedString:"headerFooterTitle"],
+                              [self localizedString:"headerFooterURL"],
+                              [self localizedString:"headerFooterDate"],
+                              [self localizedString:"headerFooterPage"],
+                              [self localizedString:"headerFooterPageTotal"],
+                              nil];
+  [list addItemsWithTitles:items];
+
+  NS_ConvertUTF16toUTF8 currentStringUTF8(aCurrentString);
+  for (unsigned int i = 0; i < ArrayLength(sHeaderFooterTags); i++) {
+    if (!strcmp(currentStringUTF8.get(), sHeaderFooterTags[i])) {
+      [list selectItemAtIndex:i];
+      break;
+    }
+  }
+
+  return list;
+}
+
+// Build sections
+
+- (void)addOptionsSection
+{
+  // Title
+  [self addLabel:"optionsTitleMac" withFrame:NSMakeRect(0, 240, 151, 22)];
+
+  // "Print Selection Only"
+  mPrintSelectionOnlyCheckbox = [self checkboxWithLabel:"selectionOnly"
+                                               andFrame:NSMakeRect(156, 240, 0, 0)];
+
+  bool canPrintSelection;
+  mSettings->GetPrintOptions(nsIPrintSettings::kEnableSelectionRB,
+                             &canPrintSelection);
+  [mPrintSelectionOnlyCheckbox setEnabled:canPrintSelection];
+
+  int16_t printRange;
+  mSettings->GetPrintRange(&printRange);
+  if (printRange == nsIPrintSettings::kRangeSelection) {
+    [mPrintSelectionOnlyCheckbox setState:NSOnState];
+  }
+
+  [self addSubview:mPrintSelectionOnlyCheckbox];
+
+  // "Shrink To Fit"
+  mShrinkToFitCheckbox = [self checkboxWithLabel:"shrinkToFit"
+                                        andFrame:NSMakeRect(156, 218, 0, 0)];
+
+  bool shrinkToFit;
+  mSettings->GetShrinkToFit(&shrinkToFit);
+  [mShrinkToFitCheckbox setState:(shrinkToFit ? NSOnState : NSOffState)];
+
+  [self addSubview:mShrinkToFitCheckbox];
+}
+
+- (void)addAppearanceSection
+{
+  // Title
+  [self addLabel:"appearanceTitleMac" withFrame:NSMakeRect(0, 188, 151, 22)];
+
+  // "Print Background Colors"
+  mPrintBGColorsCheckbox = [self checkboxWithLabel:"printBGColors"
+                                          andFrame:NSMakeRect(156, 188, 0, 0)];
+
+  bool geckoBool;
+  mSettings->GetPrintBGColors(&geckoBool);
+  [mPrintBGColorsCheckbox setState:(geckoBool ? NSOnState : NSOffState)];
+
+  [self addSubview:mPrintBGColorsCheckbox];
+
+  // "Print Background Images"
+  mPrintBGImagesCheckbox = [self checkboxWithLabel:"printBGImages"
+                                          andFrame:NSMakeRect(156, 166, 0, 0)];
+
+  mSettings->GetPrintBGImages(&geckoBool);
+  [mPrintBGImagesCheckbox setState:(geckoBool ? NSOnState : NSOffState)];
+
+  [self addSubview:mPrintBGImagesCheckbox];
+}
+
+- (void)addFramesSection
+{
+  // Title
+  [self addLabel:"framesTitleMac" withFrame:NSMakeRect(0, 124, 151, 22)];
+
+  // Radio matrix
+  NSButtonCell *radio = [[NSButtonCell alloc] init];
+  [radio setButtonType:NSRadioButton];
+  [radio setFont:[NSFont systemFontOfSize:[NSFont systemFontSize]]];
+  NSMatrix *matrix = [[NSMatrix alloc] initWithFrame:NSMakeRect(156, 81, 400, 66)
+                                                mode:NSRadioModeMatrix
+                                           prototype:(NSCell*)radio
+                                        numberOfRows:3
+                                     numberOfColumns:1];
+  [radio release];
+  [matrix setCellSize:NSMakeSize(400, 21)];
+  [self addSubview:matrix];
+  [matrix release];
+  NSArray *cellArray = [matrix cells];
+  mAsLaidOutRadio = [cellArray objectAtIndex:0];
+  mSelectedFrameRadio = [cellArray objectAtIndex:1];
+  mSeparateFramesRadio = [cellArray objectAtIndex:2];
+  [mAsLaidOutRadio setTitle:[self localizedString:"asLaidOut"]];
+  [mSelectedFrameRadio setTitle:[self localizedString:"selectedFrame"]];
+  [mSeparateFramesRadio setTitle:[self localizedString:"separateFrames"]];
+
+  // Radio enabled state
+  int16_t frameUIFlag;
+  mSettings->GetHowToEnableFrameUI(&frameUIFlag);
+  if (frameUIFlag == nsIPrintSettings::kFrameEnableNone) {
+    [mAsLaidOutRadio setEnabled:NO];
+    [mSelectedFrameRadio setEnabled:NO];
+    [mSeparateFramesRadio setEnabled:NO];
+  } else if (frameUIFlag == nsIPrintSettings::kFrameEnableAsIsAndEach) {
+    [mSelectedFrameRadio setEnabled:NO];
+  }
+
+  // Radio values
+  int16_t printFrameType;
+  mSettings->GetPrintFrameType(&printFrameType);
+  switch (printFrameType) {
+    case nsIPrintSettings::kFramesAsIs:
+      [mAsLaidOutRadio setState:NSOnState];
+      break;
+    case nsIPrintSettings::kSelectedFrame:
+      [mSelectedFrameRadio setState:NSOnState];
+      break;
+    case nsIPrintSettings::kEachFrameSep:
+      [mSeparateFramesRadio setState:NSOnState];
+      break;
+  }
+}
+
+- (void)addHeaderFooterSection
+{
+  // Labels
+  [self addLabel:"pageHeadersTitleMac" withFrame:NSMakeRect(0, 44, 151, 22)];
+  [self addLabel:"pageFootersTitleMac" withFrame:NSMakeRect(0, 0, 151, 22)];
+  [self addCenteredLabel:"left" withFrame:NSMakeRect(156, 22, 100, 22)];
+  [self addCenteredLabel:"center" withFrame:NSMakeRect(256, 22, 100, 22)];
+  [self addCenteredLabel:"right" withFrame:NSMakeRect(356, 22, 100, 22)];
+
+  // Lists
+  nsXPIDLString sel;
+
+  mSettings->GetHeaderStrLeft(getter_Copies(sel));
+  mHeaderLeftList = [self headerFooterItemListWithFrame:NSMakeRect(156, 44, 100, 22)
+                                           selectedItem:sel];
+  [self addSubview:mHeaderLeftList];
+
+  mSettings->GetHeaderStrCenter(getter_Copies(sel));
+  mHeaderCenterList = [self headerFooterItemListWithFrame:NSMakeRect(256, 44, 100, 22)
+                                             selectedItem:sel];
+  [self addSubview:mHeaderCenterList];
+
+  mSettings->GetHeaderStrRight(getter_Copies(sel));
+  mHeaderRightList = [self headerFooterItemListWithFrame:NSMakeRect(356, 44, 100, 22)
+                                            selectedItem:sel];
+  [self addSubview:mHeaderRightList];
+
+  mSettings->GetFooterStrLeft(getter_Copies(sel));
+  mFooterLeftList = [self headerFooterItemListWithFrame:NSMakeRect(156, 0, 100, 22)
+                                           selectedItem:sel];
+  [self addSubview:mFooterLeftList];
+
+  mSettings->GetFooterStrCenter(getter_Copies(sel));
+  mFooterCenterList = [self headerFooterItemListWithFrame:NSMakeRect(256, 0, 100, 22)
+                                             selectedItem:sel];
+  [self addSubview:mFooterCenterList];
+
+  mSettings->GetFooterStrRight(getter_Copies(sel));
+  mFooterRightList = [self headerFooterItemListWithFrame:NSMakeRect(356, 0, 100, 22)
+                                            selectedItem:sel];
+  [self addSubview:mFooterRightList];
+}
+
+// Export settings
+
+- (int16_t)chosenFrameSetting
+{
+  if ([mAsLaidOutRadio state] == NSOnState)
+    return nsIPrintSettings::kFramesAsIs;
+  if ([mSelectedFrameRadio state] == NSOnState)
+    return nsIPrintSettings::kSelectedFrame;
+  if ([mSeparateFramesRadio state] == NSOnState)
+    return nsIPrintSettings::kEachFrameSep;
+  return nsIPrintSettings::kNoFrames;
+}
+
+- (const char*)headerFooterStringForList:(NSPopUpButton*)aList
+{
+  NSInteger index = [aList indexOfSelectedItem];
+  NS_ASSERTION(index < NSInteger(ArrayLength(sHeaderFooterTags)), "Index of dropdown is higher than expected!");
+  return sHeaderFooterTags[index];
+}
+
+- (void)exportHeaderFooterSettings
+{
+  const char* headerFooterStr;
+  headerFooterStr = [self headerFooterStringForList:mHeaderLeftList];
+  mSettings->SetHeaderStrLeft(NS_ConvertUTF8toUTF16(headerFooterStr).get());
+
+  headerFooterStr = [self headerFooterStringForList:mHeaderCenterList];
+  mSettings->SetHeaderStrCenter(NS_ConvertUTF8toUTF16(headerFooterStr).get());
+
+  headerFooterStr = [self headerFooterStringForList:mHeaderRightList];
+  mSettings->SetHeaderStrRight(NS_ConvertUTF8toUTF16(headerFooterStr).get());
+
+  headerFooterStr = [self headerFooterStringForList:mFooterLeftList];
+  mSettings->SetFooterStrLeft(NS_ConvertUTF8toUTF16(headerFooterStr).get());
+
+  headerFooterStr = [self headerFooterStringForList:mFooterCenterList];
+  mSettings->SetFooterStrCenter(NS_ConvertUTF8toUTF16(headerFooterStr).get());
+
+  headerFooterStr = [self headerFooterStringForList:mFooterRightList];
+  mSettings->SetFooterStrRight(NS_ConvertUTF8toUTF16(headerFooterStr).get());
+}
+
+// Summary
+
+- (NSString*)summaryValueForCheckbox:(NSButton*)aCheckbox
+{
+  if (![aCheckbox isEnabled])
+    return [self localizedString:"summaryNAValue"];
+
+  return [aCheckbox state] == NSOnState ?
+    [self localizedString:"summaryOnValue"] :
+    [self localizedString:"summaryOffValue"];
+}
+
+- (NSString*)framesSummaryValue
+{
+  switch([self chosenFrameSetting]) {
+    case nsIPrintSettings::kFramesAsIs:
+      return [self localizedString:"asLaidOut"];
+    case nsIPrintSettings::kSelectedFrame:
+      return [self localizedString:"selectedFrame"];
+    case nsIPrintSettings::kEachFrameSep:
+      return [self localizedString:"separateFrames"];
+  }
+  return [self localizedString:"summaryNAValue"];
+}
+
+- (NSString*)headerSummaryValue
+{
+  return [[mHeaderLeftList titleOfSelectedItem] stringByAppendingString:
+    [@", " stringByAppendingString:
+      [[mHeaderCenterList titleOfSelectedItem] stringByAppendingString:
+        [@", " stringByAppendingString:
+          [mHeaderRightList titleOfSelectedItem]]]]];
+}
+
+- (NSString*)footerSummaryValue
+{
+  return [[mFooterLeftList titleOfSelectedItem] stringByAppendingString:
+    [@", " stringByAppendingString:
+      [[mFooterCenterList titleOfSelectedItem] stringByAppendingString:
+        [@", " stringByAppendingString:
+          [mFooterRightList titleOfSelectedItem]]]]];
+}
+
+- (NSArray*)localizedSummaryItems
+{
+  return [NSArray arrayWithObjects:
+    [NSDictionary dictionaryWithObjectsAndKeys:
+      [self localizedString:"summaryFramesTitle"], NSPrintPanelAccessorySummaryItemNameKey,
+      [self framesSummaryValue], NSPrintPanelAccessorySummaryItemDescriptionKey, nil],
+    [NSDictionary dictionaryWithObjectsAndKeys:
+      [self localizedString:"summarySelectionOnlyTitle"], NSPrintPanelAccessorySummaryItemNameKey,
+      [self summaryValueForCheckbox:mPrintSelectionOnlyCheckbox], NSPrintPanelAccessorySummaryItemDescriptionKey, nil],
+    [NSDictionary dictionaryWithObjectsAndKeys:
+      [self localizedString:"summaryShrinkToFitTitle"], NSPrintPanelAccessorySummaryItemNameKey,
+      [self summaryValueForCheckbox:mShrinkToFitCheckbox], NSPrintPanelAccessorySummaryItemDescriptionKey, nil],
+    [NSDictionary dictionaryWithObjectsAndKeys:
+      [self localizedString:"summaryPrintBGColorsTitle"], NSPrintPanelAccessorySummaryItemNameKey,
+      [self summaryValueForCheckbox:mPrintBGColorsCheckbox], NSPrintPanelAccessorySummaryItemDescriptionKey, nil],
+    [NSDictionary dictionaryWithObjectsAndKeys:
+      [self localizedString:"summaryPrintBGImagesTitle"], NSPrintPanelAccessorySummaryItemNameKey,
+      [self summaryValueForCheckbox:mPrintBGImagesCheckbox], NSPrintPanelAccessorySummaryItemDescriptionKey, nil],
+    [NSDictionary dictionaryWithObjectsAndKeys:
+      [self localizedString:"summaryHeaderTitle"], NSPrintPanelAccessorySummaryItemNameKey,
+      [self headerSummaryValue], NSPrintPanelAccessorySummaryItemDescriptionKey, nil],
+    [NSDictionary dictionaryWithObjectsAndKeys:
+      [self localizedString:"summaryFooterTitle"], NSPrintPanelAccessorySummaryItemNameKey,
+      [self footerSummaryValue], NSPrintPanelAccessorySummaryItemDescriptionKey, nil],
+    nil];
+}
+
+@end
+
+// Accessory controller
+
+@implementation PrintPanelAccessoryController
+
+- (id)initWithSettings:(nsIPrintSettings*)aSettings
+{
+  [super initWithNibName:nil bundle:nil];
+
+  NSView* accView = [[PrintPanelAccessoryView alloc] initWithSettings:aSettings];
+  [self setView:accView];
+  [accView release];
+  return self;
+}
+
+- (void)exportSettings
+{
+  return [(PrintPanelAccessoryView*)[self view] exportSettings];
+}
+
+- (NSArray *)localizedSummaryItems
+{
+  return [(PrintPanelAccessoryView*)[self view] localizedSummaryItems];
+}
+
+@end
diff --git a/widget/cocoa/nsPrintOptionsX.h b/widget/cocoa/nsPrintOptionsX.h
new file mode 100644
index 0000000000..e34e75059e
--- /dev/null
+++ b/widget/cocoa/nsPrintOptionsX.h
@@ -0,0 +1,44 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsPrintOptionsX_h_
+#define nsPrintOptionsX_h_
+
+#include "nsPrintOptionsImpl.h"
+
+namespace mozilla
+{
+namespace embedding
+{
+  class PrintData;
+} // namespace embedding
+} // namespace mozilla
+
+class nsPrintOptionsX : public nsPrintOptions
+{
+public:
+             nsPrintOptionsX();
+  virtual    ~nsPrintOptionsX();
+
+  /*
+   * These serialize and deserialize methods are not symmetrical in that
+   * printSettingsX != deserialize(serialize(printSettingsX)). This is because
+   * the native print settings stored in the nsPrintSettingsX's NSPrintInfo
+   * object are not fully serialized. Only the values needed for successful
+   * printing are.
+   */
+  NS_IMETHODIMP SerializeToPrintData(nsIPrintSettings* aSettings,
+                                     nsIWebBrowserPrint* aWBP,
+                                     mozilla::embedding::PrintData* data);
+  NS_IMETHODIMP DeserializeToPrintSettings(const mozilla::embedding::PrintData& data,
+                                           nsIPrintSettings* settings);
+
+protected:
+  nsresult   _CreatePrintSettings(nsIPrintSettings **_retval);
+  nsresult   ReadPrefs(nsIPrintSettings* aPS, const nsAString& aPrinterName, uint32_t aFlags);
+  nsresult   WritePrefs(nsIPrintSettings* aPS, const nsAString& aPrinterName, uint32_t aFlags);
+};
+
+#endif // nsPrintOptionsX_h_
diff --git a/widget/cocoa/nsPrintOptionsX.mm b/widget/cocoa/nsPrintOptionsX.mm
new file mode 100644
index 0000000000..d9aa17b42e
--- /dev/null
+++ b/widget/cocoa/nsPrintOptionsX.mm
@@ -0,0 +1,349 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsCOMPtr.h"
+#include "nsQueryObject.h"
+#include "nsIServiceManager.h"
+#include "nsPrintOptionsX.h"
+#include "nsPrintSettingsX.h"
+
+// The constants for paper orientation were renamed in 10.9. __MAC_10_9 is
+// defined on OS X 10.9 and later. Although 10.8 and earlier are not supported
+// at this time, this allows for building on those older OS versions. The
+// values are consistent across OS versions so the rename does not affect
+// runtime, just compilation.
+#ifdef __MAC_10_9
+#define NS_PAPER_ORIENTATION_PORTRAIT   (NSPaperOrientationPortrait)
+#define NS_PAPER_ORIENTATION_LANDSCAPE  (NSPaperOrientationLandscape)
+#else
+#define NS_PAPER_ORIENTATION_PORTRAIT   (NSPortraitOrientation)
+#define NS_PAPER_ORIENTATION_LANDSCAPE  (NSLandscapeOrientation)
+#endif
+
+using namespace mozilla::embedding;
+
+nsPrintOptionsX::nsPrintOptionsX()
+{
+}
+
+nsPrintOptionsX::~nsPrintOptionsX()
+{
+}
+
+NS_IMETHODIMP
+nsPrintOptionsX::SerializeToPrintData(nsIPrintSettings* aSettings,
+                                      nsIWebBrowserPrint* aWBP,
+                                      PrintData* data)
+{
+  nsresult rv = nsPrintOptions::SerializeToPrintData(aSettings, aWBP, data);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  if (aWBP) {
+    // When serializing an nsIWebBrowserPrint, we need to pass up the first
+    // document name. We could pass up the entire collection of document
+    // names, but the OS X printing prompt code only really cares about
+    // the first one, so we just send the first to save IPC traffic.
+    char16_t** docTitles;
+    uint32_t titleCount;
+    rv = aWBP->EnumerateDocumentNames(&titleCount, &docTitles);
+    if (NS_SUCCEEDED(rv) && titleCount > 0) {
+      data->printJobName().Assign(docTitles[0]);
+    }
+
+    for (int32_t i = titleCount - 1; i >= 0; i--) {
+      free(docTitles[i]);
+    }
+    free(docTitles);
+    docTitles = nullptr;
+  }
+
+  RefPtr<nsPrintSettingsX> settingsX(do_QueryObject(aSettings));
+  if (NS_WARN_IF(!settingsX)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NSPrintInfo* printInfo = settingsX->GetCocoaPrintInfo();
+  if (NS_WARN_IF(!printInfo)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  double adjustedWidth, adjustedHeight;
+  settingsX->GetAdjustedPaperSize(&adjustedWidth, &adjustedHeight);
+  data->adjustedPaperWidth() = adjustedWidth;
+  data->adjustedPaperHeight() = adjustedHeight;
+
+  NSDictionary* dict = [printInfo dictionary];
+  if (NS_WARN_IF(!dict)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NSString* printerName = [dict objectForKey: NSPrintPrinterName];
+  if (printerName) {
+    nsCocoaUtils::GetStringForNSString(printerName, data->printerName());
+  }
+
+  NSString* faxNumber = [dict objectForKey: NSPrintFaxNumber];
+  if (faxNumber) {
+    nsCocoaUtils::GetStringForNSString(faxNumber, data->faxNumber());
+  }
+
+  NSURL* printToFileURL = [dict objectForKey: NSPrintJobSavingURL];
+  if (printToFileURL) {
+    nsCocoaUtils::GetStringForNSString([printToFileURL absoluteString],
+                                       data->toFileName());
+  }
+
+  NSDate* printTime = [dict objectForKey: NSPrintTime];
+  if (printTime) {
+    NSTimeInterval timestamp = [printTime timeIntervalSinceReferenceDate];
+    data->printTime() = timestamp;
+  }
+
+  NSString* disposition = [dict objectForKey: NSPrintJobDisposition];
+  if (disposition) {
+    nsCocoaUtils::GetStringForNSString(disposition, data->disposition());
+  }
+
+  NSString* paperName = [dict objectForKey: NSPrintPaperName];
+  if (paperName) {
+    nsCocoaUtils::GetStringForNSString(paperName, data->paperName());
+  }
+
+  float scalingFactor = [[dict objectForKey: NSPrintScalingFactor] floatValue];
+  data->scalingFactor() = scalingFactor;
+
+  int32_t orientation;
+  if ([printInfo orientation] == NS_PAPER_ORIENTATION_PORTRAIT) {
+    orientation = nsIPrintSettings::kPortraitOrientation;
+  } else {
+    orientation = nsIPrintSettings::kLandscapeOrientation;
+  }
+  data->orientation() = orientation;
+
+  NSSize paperSize = [printInfo paperSize];
+  float widthScale, heightScale;
+  settingsX->GetInchesScale(&widthScale, &heightScale);
+  if (orientation == nsIPrintSettings::kLandscapeOrientation) {
+    // switch widths and heights
+    data->widthScale() = heightScale;
+    data->heightScale() = widthScale;
+    data->paperWidth() = paperSize.height / heightScale;
+    data->paperHeight() = paperSize.width / widthScale;
+  } else {
+    data->widthScale() = widthScale;
+    data->heightScale() = heightScale;
+    data->paperWidth() = paperSize.width / widthScale;
+    data->paperHeight() = paperSize.height / heightScale;
+  }
+
+  data->numCopies() = [[dict objectForKey: NSPrintCopies] intValue];
+  data->printAllPages() = [[dict objectForKey: NSPrintAllPages] boolValue];
+  data->startPageRange() = [[dict objectForKey: NSPrintFirstPage] intValue];
+  data->endPageRange() = [[dict objectForKey: NSPrintLastPage] intValue];
+  data->mustCollate() = [[dict objectForKey: NSPrintMustCollate] boolValue];
+  data->printReversed() = [[dict objectForKey: NSPrintReversePageOrder] boolValue];
+  data->pagesAcross() = [[dict objectForKey: NSPrintPagesAcross] unsignedShortValue];
+  data->pagesDown() = [[dict objectForKey: NSPrintPagesDown] unsignedShortValue];
+  data->detailedErrorReporting() = [[dict objectForKey: NSPrintDetailedErrorReporting] boolValue];
+  data->addHeaderAndFooter() = [[dict objectForKey: NSPrintHeaderAndFooter] boolValue];
+  data->fileNameExtensionHidden() =
+    [[dict objectForKey: NSPrintJobSavingFileNameExtensionHidden] boolValue];
+
+  bool printSelectionOnly = [[dict objectForKey: NSPrintSelectionOnly] boolValue];
+  aSettings->SetPrintOptions(nsIPrintSettings::kEnableSelectionRB,
+                             printSelectionOnly);
+  aSettings->GetPrintOptionsBits(&data->optionFlags());
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsPrintOptionsX::DeserializeToPrintSettings(const PrintData& data,
+                                            nsIPrintSettings* settings)
+{
+  nsresult rv = nsPrintOptions::DeserializeToPrintSettings(data, settings);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  RefPtr<nsPrintSettingsX> settingsX(do_QueryObject(settings));
+  if (NS_WARN_IF(!settingsX)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NSPrintInfo* sharedPrintInfo = [NSPrintInfo sharedPrintInfo];
+  if (NS_WARN_IF(!sharedPrintInfo)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  NSDictionary* sharedDict = [sharedPrintInfo dictionary];
+  if (NS_WARN_IF(!sharedDict)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // We need to create a new NSMutableDictionary to pass to NSPrintInfo with
+  // the values that we got from the other process.
+  NSMutableDictionary* newPrintInfoDict =
+    [NSMutableDictionary dictionaryWithDictionary:sharedDict];
+  if (NS_WARN_IF(!newPrintInfoDict)) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  NSString* printerName = nsCocoaUtils::ToNSString(data.printerName());
+  if (printerName) {
+    NSPrinter* printer = [NSPrinter printerWithName: printerName];
+    if (printer) {
+      [newPrintInfoDict setObject: printer forKey: NSPrintPrinter];
+      [newPrintInfoDict setObject: printerName forKey: NSPrintPrinterName];
+    }
+  }
+
+  [newPrintInfoDict setObject: [NSNumber numberWithInt: data.numCopies()]
+                    forKey: NSPrintCopies];
+  [newPrintInfoDict setObject: [NSNumber numberWithBool: data.printAllPages()]
+                    forKey: NSPrintAllPages];
+  [newPrintInfoDict setObject: [NSNumber numberWithInt: data.startPageRange()]
+                    forKey: NSPrintFirstPage];
+  [newPrintInfoDict setObject: [NSNumber numberWithInt: data.endPageRange()]
+                    forKey: NSPrintLastPage];
+  [newPrintInfoDict setObject: [NSNumber numberWithBool: data.mustCollate()]
+                    forKey: NSPrintMustCollate];
+  [newPrintInfoDict setObject: [NSNumber numberWithBool: data.printReversed()]
+                    forKey: NSPrintReversePageOrder];
+
+  [newPrintInfoDict setObject: nsCocoaUtils::ToNSString(data.disposition())
+                    forKey: NSPrintJobDisposition];
+
+  [newPrintInfoDict setObject: nsCocoaUtils::ToNSString(data.paperName())
+                    forKey: NSPrintPaperName];
+
+  [newPrintInfoDict setObject: [NSNumber numberWithFloat: data.scalingFactor()]
+                    forKey: NSPrintScalingFactor];
+
+  CGFloat width = data.paperWidth() * data.widthScale();
+  CGFloat height = data.paperHeight() * data.heightScale();
+  [newPrintInfoDict setObject: [NSValue valueWithSize:NSMakeSize(width,height)]
+                    forKey: NSPrintPaperSize];
+
+  int paperOrientation;
+  if (data.orientation() == nsIPrintSettings::kPortraitOrientation) {
+    paperOrientation = NS_PAPER_ORIENTATION_PORTRAIT;
+    settings->SetOrientation(nsIPrintSettings::kPortraitOrientation);
+  } else {
+    paperOrientation = NS_PAPER_ORIENTATION_LANDSCAPE;
+    settings->SetOrientation(nsIPrintSettings::kLandscapeOrientation);
+  }
+  [newPrintInfoDict setObject: [NSNumber numberWithInt:paperOrientation]
+                    forKey: NSPrintOrientation];
+
+  [newPrintInfoDict setObject: [NSNumber numberWithShort: data.pagesAcross()]
+                    forKey: NSPrintPagesAcross];
+  [newPrintInfoDict setObject: [NSNumber numberWithShort: data.pagesDown()]
+                    forKey: NSPrintPagesDown];
+  [newPrintInfoDict setObject: [NSNumber numberWithBool: data.detailedErrorReporting()]
+                    forKey: NSPrintDetailedErrorReporting];
+  [newPrintInfoDict setObject: nsCocoaUtils::ToNSString(data.faxNumber())
+                    forKey: NSPrintFaxNumber];
+  [newPrintInfoDict setObject: [NSNumber numberWithBool: data.addHeaderAndFooter()]
+                    forKey: NSPrintHeaderAndFooter];
+  [newPrintInfoDict setObject: [NSNumber numberWithBool: data.fileNameExtensionHidden()]
+                    forKey: NSPrintJobSavingFileNameExtensionHidden];
+
+  // At this point, the base class should have properly deserialized the print
+  // options bitfield for nsIPrintSettings, so that it holds the correct value
+  // for kEnableSelectionRB, which we use to set NSPrintSelectionOnly.
+
+  bool printSelectionOnly = false;
+  rv = settings->GetPrintOptions(nsIPrintSettings::kEnableSelectionRB, &printSelectionOnly);
+  if (NS_SUCCEEDED(rv)) {
+    [newPrintInfoDict setObject: [NSNumber numberWithBool: printSelectionOnly]
+                      forKey: NSPrintSelectionOnly];
+  } else {
+    [newPrintInfoDict setObject: [NSNumber numberWithBool: NO]
+                      forKey: NSPrintSelectionOnly];
+  }
+
+  NSURL* jobSavingURL =
+    [NSURL URLWithString: nsCocoaUtils::ToNSString(data.toFileName())];
+  if (jobSavingURL) {
+    [newPrintInfoDict setObject: jobSavingURL forKey: NSPrintJobSavingURL];
+  }
+
+  NSTimeInterval timestamp = data.printTime();
+  NSDate* printTime = [NSDate dateWithTimeIntervalSinceReferenceDate: timestamp];
+  if (printTime) {
+    [newPrintInfoDict setObject: printTime forKey: NSPrintTime];
+  }
+
+  // Next, we create a new NSPrintInfo with the values in our dictionary.
+  NSPrintInfo* newPrintInfo =
+    [[NSPrintInfo alloc] initWithDictionary: newPrintInfoDict];
+  if (NS_WARN_IF(!newPrintInfo)) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  // And now swap in the new NSPrintInfo we've just populated.
+  settingsX->SetCocoaPrintInfo(newPrintInfo);
+  [newPrintInfo release];
+
+  settingsX->SetAdjustedPaperSize(data.adjustedPaperWidth(),
+                                  data.adjustedPaperHeight());
+
+  return NS_OK;
+}
+
+nsresult
+nsPrintOptionsX::ReadPrefs(nsIPrintSettings* aPS, const nsAString& aPrinterName, uint32_t aFlags)
+{
+  nsresult rv;
+  
+  rv = nsPrintOptions::ReadPrefs(aPS, aPrinterName, aFlags);
+  NS_ASSERTION(NS_SUCCEEDED(rv), "nsPrintOptions::ReadPrefs() failed");
+  
+  RefPtr<nsPrintSettingsX> printSettingsX(do_QueryObject(aPS));
+  if (!printSettingsX)
+    return NS_ERROR_NO_INTERFACE;
+  rv = printSettingsX->ReadPageFormatFromPrefs();
+  
+  return NS_OK;
+}
+
+nsresult nsPrintOptionsX::_CreatePrintSettings(nsIPrintSettings **_retval)
+{
+  nsresult rv;
+  *_retval = nullptr;
+
+  nsPrintSettingsX* printSettings = new nsPrintSettingsX; // does not initially ref count
+  NS_ENSURE_TRUE(printSettings, NS_ERROR_OUT_OF_MEMORY);
+  NS_ADDREF(*_retval = printSettings);
+
+  rv = printSettings->Init();
+  if (NS_FAILED(rv)) {
+    NS_RELEASE(*_retval);
+    return rv;
+  }
+
+  InitPrintSettingsFromPrefs(*_retval, false, nsIPrintSettings::kInitSaveAll);
+  return rv;
+}
+
+nsresult
+nsPrintOptionsX::WritePrefs(nsIPrintSettings* aPS, const nsAString& aPrinterName, uint32_t aFlags)
+{
+  nsresult rv;
+
+  rv = nsPrintOptions::WritePrefs(aPS, aPrinterName, aFlags);
+  NS_ASSERTION(NS_SUCCEEDED(rv), "nsPrintOptions::WritePrefs() failed");
+
+  RefPtr<nsPrintSettingsX> printSettingsX(do_QueryObject(aPS));
+  if (!printSettingsX)
+    return NS_ERROR_NO_INTERFACE;
+  rv = printSettingsX->WritePageFormatToPrefs();
+  NS_ASSERTION(NS_SUCCEEDED(rv), "nsPrintSettingsX::WritePageFormatToPrefs() failed");
+
+  return NS_OK;
+}
diff --git a/widget/cocoa/nsPrintSettingsX.h b/widget/cocoa/nsPrintSettingsX.h
new file mode 100644
index 0000000000..1d755b2505
--- /dev/null
+++ b/widget/cocoa/nsPrintSettingsX.h
@@ -0,0 +1,82 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsPrintSettingsX_h_
+#define nsPrintSettingsX_h_
+
+#include "nsPrintSettingsImpl.h"  
+#import <Cocoa/Cocoa.h>
+
+#define NS_PRINTSETTINGSX_IID \
+{ 0x0DF2FDBD, 0x906D, 0x4726, \
+  { 0x9E, 0x4D, 0xCF, 0xE0, 0x87, 0x8D, 0x70, 0x7C } }
+
+class nsPrintSettingsX : public nsPrintSettings
+{
+public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_PRINTSETTINGSX_IID)
+  NS_DECL_ISUPPORTS_INHERITED
+
+  nsPrintSettingsX();
+  nsresult Init();
+  NSPrintInfo* GetCocoaPrintInfo() { return mPrintInfo; }
+  void SetCocoaPrintInfo(NSPrintInfo* aPrintInfo);
+  virtual nsresult ReadPageFormatFromPrefs();
+  virtual nsresult WritePageFormatToPrefs();
+  virtual nsresult GetEffectivePageSize(double *aWidth,
+      double *aHeight) override;
+
+  // In addition to setting the paper width and height, these
+  // overrides set the adjusted width and height returned from
+  // GetEffectivePageSize. This is needed when a paper size is
+  // set manually without using a print dialog a la reftest-print.
+  virtual nsresult SetPaperWidth(double aPaperWidth) override;
+  virtual nsresult SetPaperHeight(double aPaperWidth) override;
+
+  PMPrintSettings GetPMPrintSettings();
+  PMPrintSession GetPMPrintSession();
+  PMPageFormat GetPMPageFormat();
+  void SetPMPageFormat(PMPageFormat aPageFormat);
+
+  // Re-initialize mUnwriteableMargin with values from mPageFormat.
+  // Should be called whenever mPageFormat is initialized or overwritten.
+  nsresult InitUnwriteableMargin();
+
+  // Re-initialize mAdjustedPaper{Width,Height} with values from mPageFormat.
+  // Should be called whenever mPageFormat is initialized or overwritten.
+  nsresult InitAdjustedPaperSize();
+
+  void SetInchesScale(float aWidthScale, float aHeightScale);
+  void GetInchesScale(float *aWidthScale, float *aHeightScale);
+
+  void SetAdjustedPaperSize(double aWidth, double aHeight);
+  void GetAdjustedPaperSize(double *aWidth, double *aHeight);
+
+protected:
+  virtual ~nsPrintSettingsX();
+
+  nsPrintSettingsX(const nsPrintSettingsX& src);
+  nsPrintSettingsX& operator=(const nsPrintSettingsX& rhs);
+
+  nsresult _Clone(nsIPrintSettings **_retval) override;
+  nsresult _Assign(nsIPrintSettings *aPS) override;
+
+  // The out param has a ref count of 1 on return so caller needs to PMRelase() when done.
+  OSStatus CreateDefaultPageFormat(PMPrintSession aSession, PMPageFormat& outFormat);
+  OSStatus CreateDefaultPrintSettings(PMPrintSession aSession, PMPrintSettings& outSettings);
+
+  NSPrintInfo* mPrintInfo;
+
+  // Scaling factors used to convert the NSPrintInfo
+  // paper size units to inches
+  float mWidthScale;
+  float mHeightScale;
+  double mAdjustedPaperWidth;
+  double mAdjustedPaperHeight;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsPrintSettingsX, NS_PRINTSETTINGSX_IID)
+
+#endif // nsPrintSettingsX_h_
diff --git a/widget/cocoa/nsPrintSettingsX.mm b/widget/cocoa/nsPrintSettingsX.mm
new file mode 100644
index 0000000000..73a8e78d2b
--- /dev/null
+++ b/widget/cocoa/nsPrintSettingsX.mm
@@ -0,0 +1,272 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsPrintSettingsX.h"
+#include "nsObjCExceptions.h"
+
+#include "plbase64.h"
+#include "plstr.h"
+
+#include "nsCocoaUtils.h"
+
+#include "mozilla/Preferences.h"
+
+using namespace mozilla;
+
+#define MAC_OS_X_PAGE_SETUP_PREFNAME    "print.macosx.pagesetup-2"
+#define COCOA_PAPER_UNITS_PER_INCH      72.0
+
+NS_IMPL_ISUPPORTS_INHERITED(nsPrintSettingsX, nsPrintSettings, nsPrintSettingsX)
+
+nsPrintSettingsX::nsPrintSettingsX()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  mPrintInfo = [[NSPrintInfo sharedPrintInfo] copy];
+  mWidthScale = COCOA_PAPER_UNITS_PER_INCH;
+  mHeightScale = COCOA_PAPER_UNITS_PER_INCH;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsPrintSettingsX::nsPrintSettingsX(const nsPrintSettingsX& src)
+{
+  *this = src;
+}
+
+nsPrintSettingsX::~nsPrintSettingsX()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mPrintInfo release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsPrintSettingsX& nsPrintSettingsX::operator=(const nsPrintSettingsX& rhs)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (this == &rhs) {
+    return *this;
+  }
+  
+  nsPrintSettings::operator=(rhs);
+
+  [mPrintInfo release];
+  mPrintInfo = [rhs.mPrintInfo copy];
+
+  return *this;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(*this);
+}
+
+nsresult nsPrintSettingsX::Init()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  InitUnwriteableMargin();
+  InitAdjustedPaperSize();
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+// Should be called whenever the page format changes.
+NS_IMETHODIMP nsPrintSettingsX::InitUnwriteableMargin()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  PMPaper paper;
+  PMPaperMargins paperMargin;
+  PMPageFormat pageFormat = GetPMPageFormat();
+  ::PMGetPageFormatPaper(pageFormat, &paper);
+  ::PMPaperGetMargins(paper, &paperMargin);
+  mUnwriteableMargin.top    = NS_POINTS_TO_INT_TWIPS(paperMargin.top);
+  mUnwriteableMargin.left   = NS_POINTS_TO_INT_TWIPS(paperMargin.left);
+  mUnwriteableMargin.bottom = NS_POINTS_TO_INT_TWIPS(paperMargin.bottom);
+  mUnwriteableMargin.right  = NS_POINTS_TO_INT_TWIPS(paperMargin.right);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;  
+}
+
+NS_IMETHODIMP nsPrintSettingsX::InitAdjustedPaperSize()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  PMPageFormat pageFormat = GetPMPageFormat();
+
+  PMRect paperRect;
+  ::PMGetAdjustedPaperRect(pageFormat, &paperRect);
+
+  mAdjustedPaperWidth = paperRect.right - paperRect.left;
+  mAdjustedPaperHeight = paperRect.bottom - paperRect.top;
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void
+nsPrintSettingsX::SetCocoaPrintInfo(NSPrintInfo* aPrintInfo)
+{
+  if (mPrintInfo != aPrintInfo) {
+    [mPrintInfo release];
+    mPrintInfo = [aPrintInfo retain];
+  }
+}
+
+NS_IMETHODIMP nsPrintSettingsX::ReadPageFormatFromPrefs()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  nsAutoCString encodedData;
+  nsresult rv =
+    Preferences::GetCString(MAC_OS_X_PAGE_SETUP_PREFNAME, &encodedData);
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+
+  // decode the base64
+  char* decodedData = PL_Base64Decode(encodedData.get(), encodedData.Length(), nullptr);
+  NSData* data = [NSData dataWithBytes:decodedData length:strlen(decodedData)];
+  if (!data)
+    return NS_ERROR_FAILURE;
+
+  PMPageFormat newPageFormat;
+  OSStatus status = ::PMPageFormatCreateWithDataRepresentation((CFDataRef)data, &newPageFormat);
+  if (status == noErr) {
+    SetPMPageFormat(newPageFormat);
+  }
+  InitUnwriteableMargin();
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP nsPrintSettingsX::WritePageFormatToPrefs()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  PMPageFormat pageFormat = GetPMPageFormat();
+  if (pageFormat == kPMNoPageFormat)
+    return NS_ERROR_NOT_INITIALIZED;
+
+  NSData* data = nil;
+  OSStatus err = ::PMPageFormatCreateDataRepresentation(pageFormat, (CFDataRef*)&data, kPMDataFormatXMLDefault);
+  if (err != noErr)
+    return NS_ERROR_FAILURE;
+
+  nsAutoCString encodedData;
+  encodedData.Adopt(PL_Base64Encode((char*)[data bytes], [data length], nullptr));
+  if (!encodedData.get())
+    return NS_ERROR_OUT_OF_MEMORY;
+
+  return Preferences::SetCString(MAC_OS_X_PAGE_SETUP_PREFNAME, encodedData);
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsresult nsPrintSettingsX::_Clone(nsIPrintSettings **_retval)
+{
+  NS_ENSURE_ARG_POINTER(_retval);
+  *_retval = nullptr;
+  
+  nsPrintSettingsX *newSettings = new nsPrintSettingsX(*this);
+  if (!newSettings)
+    return NS_ERROR_FAILURE;
+  *_retval = newSettings;
+  NS_ADDREF(*_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsPrintSettingsX::_Assign(nsIPrintSettings *aPS)
+{
+  nsPrintSettingsX *printSettingsX = static_cast<nsPrintSettingsX*>(aPS);
+  if (!printSettingsX)
+    return NS_ERROR_UNEXPECTED;
+  *this = *printSettingsX;
+  return NS_OK;
+}
+
+PMPrintSettings
+nsPrintSettingsX::GetPMPrintSettings()
+{
+  return static_cast<PMPrintSettings>([mPrintInfo PMPrintSettings]);
+}
+
+PMPrintSession
+nsPrintSettingsX::GetPMPrintSession()
+{
+  return static_cast<PMPrintSession>([mPrintInfo PMPrintSession]);
+}
+
+PMPageFormat
+nsPrintSettingsX::GetPMPageFormat()
+{
+  return static_cast<PMPageFormat>([mPrintInfo PMPageFormat]);
+}
+
+void
+nsPrintSettingsX::SetPMPageFormat(PMPageFormat aPageFormat)
+{
+  PMPageFormat oldPageFormat = GetPMPageFormat();
+  ::PMCopyPageFormat(aPageFormat, oldPageFormat);
+  [mPrintInfo updateFromPMPageFormat];
+}
+
+void
+nsPrintSettingsX::SetInchesScale(float aWidthScale, float aHeightScale)
+{
+  if (aWidthScale > 0 && aHeightScale > 0) {
+    mWidthScale = aWidthScale;
+    mHeightScale = aHeightScale;
+  }
+}
+
+void
+nsPrintSettingsX::GetInchesScale(float *aWidthScale, float *aHeightScale)
+{
+  *aWidthScale = mWidthScale;
+  *aHeightScale = mHeightScale;
+}
+
+NS_IMETHODIMP nsPrintSettingsX::SetPaperWidth(double aPaperWidth)
+{
+  mPaperWidth = aPaperWidth;
+  mAdjustedPaperWidth = aPaperWidth * mWidthScale;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsPrintSettingsX::SetPaperHeight(double aPaperHeight)
+{
+  mPaperHeight = aPaperHeight;
+  mAdjustedPaperHeight = aPaperHeight * mHeightScale;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsPrintSettingsX::GetEffectivePageSize(double *aWidth, double *aHeight)
+{
+  *aWidth  = NS_INCHES_TO_TWIPS(mAdjustedPaperWidth / mWidthScale);
+  *aHeight = NS_INCHES_TO_TWIPS(mAdjustedPaperHeight / mHeightScale);
+  return NS_OK;
+}
+
+void nsPrintSettingsX::SetAdjustedPaperSize(double aWidth, double aHeight)
+{
+  mAdjustedPaperWidth = aWidth;
+  mAdjustedPaperHeight = aHeight;
+}
+
+void nsPrintSettingsX::GetAdjustedPaperSize(double *aWidth, double *aHeight)
+{
+  *aWidth = mAdjustedPaperWidth;
+  *aHeight = mAdjustedPaperHeight;
+}
diff --git a/widget/cocoa/nsSandboxViolationSink.h b/widget/cocoa/nsSandboxViolationSink.h
new file mode 100644
index 0000000000..35b5d89af5
--- /dev/null
+++ b/widget/cocoa/nsSandboxViolationSink.h
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsSandboxViolationSink_h_
+#define nsSandboxViolationSink_h_
+
+#include <stdint.h>
+
+// Class for tracking sandbox violations.  Currently it just logs them to
+// stdout and the system console.  In the future it may do more.
+
+// What makes this possible is the fact that Apple' sandboxd calls
+// notify_post("com.apple.sandbox.violation.*") whenever it's notified by the
+// Sandbox kernel extension of a sandbox violation.  We register to receive
+// these notifications.  But the notifications are empty, and are sent for
+// every violation in every process.  So we need to do more to get only "our"
+// violations, and to find out what kind of violation they were.  See the
+// implementation of nsSandboxViolationSink::ViolationHandler().
+
+#define SANDBOX_VIOLATION_QUEUE_NAME "org.mozilla.sandbox.violation.queue"
+#define SANDBOX_VIOLATION_NOTIFICATION_NAME "com.apple.sandbox.violation.*"
+
+class nsSandboxViolationSink
+{
+public:
+  static void Start();
+  static void Stop();
+private:
+  static void ViolationHandler();
+  static int mNotifyToken;
+  static uint64_t mLastMsgReceived;
+};
+
+#endif // nsSandboxViolationSink_h_
diff --git a/widget/cocoa/nsSandboxViolationSink.mm b/widget/cocoa/nsSandboxViolationSink.mm
new file mode 100644
index 0000000000..0572173344
--- /dev/null
+++ b/widget/cocoa/nsSandboxViolationSink.mm
@@ -0,0 +1,115 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsSandboxViolationSink.h"
+
+#include <unistd.h>
+#include <time.h>
+#include <asl.h>
+#include <dispatch/dispatch.h>
+#include <notify.h>
+#include "nsCocoaDebugUtils.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/Sprintf.h"
+
+int nsSandboxViolationSink::mNotifyToken = 0;
+uint64_t nsSandboxViolationSink::mLastMsgReceived = 0;
+
+void
+nsSandboxViolationSink::Start()
+{
+  if (mNotifyToken) {
+    return;
+  }
+  notify_register_dispatch(SANDBOX_VIOLATION_NOTIFICATION_NAME,
+                           &mNotifyToken,
+                           dispatch_queue_create(SANDBOX_VIOLATION_QUEUE_NAME,
+                                                 DISPATCH_QUEUE_SERIAL),
+                           ^(int token) { ViolationHandler(); });
+}
+
+void
+nsSandboxViolationSink::Stop()
+{
+  if (!mNotifyToken) {
+    return;
+  }
+  notify_cancel(mNotifyToken);
+  mNotifyToken = 0;
+}
+
+// We need to query syslogd to find out what violations occurred, and whether
+// they were "ours".  We can use the Apple System Log facility to do this.
+// Besides calling notify_post("com.apple.sandbox.violation.*"), Apple's
+// sandboxd also reports all sandbox violations (sent to it by the Sandbox
+// kernel extension) to syslogd, which stores them and makes them viewable
+// in the system console.  This is the database we query.
+
+// ViolationHandler() is always called on its own secondary thread.  This
+// makes it unlikely it will interfere with other browser activity.
+
+void
+nsSandboxViolationSink::ViolationHandler()
+{
+  aslmsg query = asl_new(ASL_TYPE_QUERY);
+
+  asl_set_query(query, ASL_KEY_FACILITY, "com.apple.sandbox",
+                ASL_QUERY_OP_EQUAL);
+
+  // Only get reports that were generated very recently.
+  char query_time[30] = {0};
+  SprintfLiteral(query_time, "%li", time(NULL) - 2);
+  asl_set_query(query, ASL_KEY_TIME, query_time,
+                ASL_QUERY_OP_NUMERIC | ASL_QUERY_OP_GREATER_EQUAL);
+
+  // This code is easier to test if we don't just track "our" violations,
+  // which are (normally) few and far between.  For example (for the time
+  // being at least) four appleeventsd sandbox violations happen every time
+  // we start the browser in e10s mode.  But it makes sense to default to
+  // only tracking "our" violations.
+  if (mozilla::Preferences::GetBool(
+      "security.sandbox.mac.track.violations.oursonly", true)) {
+    // This makes each of our processes log its own violations.  It might
+    // be better to make the chrome process log all the other processes'
+    // violations.
+    char query_pid[20] = {0};
+    SprintfLiteral(query_pid, "%u", getpid());
+    asl_set_query(query, ASL_KEY_REF_PID, query_pid, ASL_QUERY_OP_EQUAL);
+  }
+
+  aslresponse response = asl_search(nullptr, query);
+
+  // Each time ViolationHandler() is called we grab as many messages as are
+  // available.  Otherwise we might not get them all.
+  if (response) {
+    while (true) {
+      aslmsg hit = nullptr;
+      aslmsg found = nullptr;
+      const char* id_str;
+
+      while ((hit = aslresponse_next(response))) {
+        // Record the message id to avoid logging the same violation more
+        // than once.
+        id_str = asl_get(hit, ASL_KEY_MSG_ID);
+        uint64_t id_val = atoll(id_str);
+        if (id_val <= mLastMsgReceived) {
+          continue;
+        }
+        mLastMsgReceived = id_val;
+        found = hit;
+        break;
+      }
+      if (!found) {
+        break;
+      }
+
+      const char* pid_str = asl_get(found, ASL_KEY_REF_PID);
+      const char* message_str = asl_get(found, ASL_KEY_MSG);
+      nsCocoaDebugUtils::DebugLog("nsSandboxViolationSink::ViolationHandler(): id %s, pid %s, message %s",
+                                  id_str, pid_str, message_str);
+    }
+    aslresponse_free(response);
+  }
+}
diff --git a/widget/cocoa/nsScreenCocoa.h b/widget/cocoa/nsScreenCocoa.h
new file mode 100644
index 0000000000..268d5beb0a
--- /dev/null
+++ b/widget/cocoa/nsScreenCocoa.h
@@ -0,0 +1,41 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsScreenCocoa_h_
+#define nsScreenCocoa_h_
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsBaseScreen.h"
+
+class nsScreenCocoa : public nsBaseScreen
+{
+public:
+    explicit nsScreenCocoa (NSScreen *screen);
+    ~nsScreenCocoa ();
+
+    NS_IMETHOD GetId(uint32_t* outId);
+    NS_IMETHOD GetRect(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetAvailRect(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetRectDisplayPix(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetAvailRectDisplayPix(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetPixelDepth(int32_t* aPixelDepth);
+    NS_IMETHOD GetColorDepth(int32_t* aColorDepth);
+    NS_IMETHOD GetContentsScaleFactor(double* aContentsScaleFactor);
+    NS_IMETHOD GetDefaultCSSScaleFactor(double* aScaleFactor)
+    {
+      return GetContentsScaleFactor(aScaleFactor);
+    }
+
+    NSScreen *CocoaScreen() { return mScreen; }
+
+private:
+    CGFloat BackingScaleFactor();
+
+    NSScreen *mScreen;
+    uint32_t mId;
+};
+
+#endif // nsScreenCocoa_h_
diff --git a/widget/cocoa/nsScreenCocoa.mm b/widget/cocoa/nsScreenCocoa.mm
new file mode 100644
index 0000000000..08905bf0ad
--- /dev/null
+++ b/widget/cocoa/nsScreenCocoa.mm
@@ -0,0 +1,147 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsScreenCocoa.h"
+#include "nsObjCExceptions.h"
+#include "nsCocoaUtils.h"
+
+static uint32_t sScreenId = 0;
+
+nsScreenCocoa::nsScreenCocoa (NSScreen *screen)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  mScreen = [screen retain];
+  mId = ++sScreenId;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsScreenCocoa::~nsScreenCocoa ()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mScreen release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetId(uint32_t *outId)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  *outId = mId;
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetRect(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+  NSRect frame = [mScreen frame];
+
+  mozilla::LayoutDeviceIntRect r =
+    nsCocoaUtils::CocoaRectToGeckoRectDevPix(frame, BackingScaleFactor());
+
+  *outX = r.x;
+  *outY = r.y;
+  *outWidth = r.width;
+  *outHeight = r.height;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetAvailRect(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+  NSRect frame = [mScreen visibleFrame];
+
+  mozilla::LayoutDeviceIntRect r =
+    nsCocoaUtils::CocoaRectToGeckoRectDevPix(frame, BackingScaleFactor());
+
+  *outX = r.x;
+  *outY = r.y;
+  *outWidth = r.width;
+  *outHeight = r.height;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetRectDisplayPix(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+  NSRect frame = [mScreen frame];
+
+  mozilla::DesktopIntRect r = nsCocoaUtils::CocoaRectToGeckoRect(frame);
+
+  *outX = r.x;
+  *outY = r.y;
+  *outWidth = r.width;
+  *outHeight = r.height;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetAvailRectDisplayPix(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+  NSRect frame = [mScreen visibleFrame];
+
+  mozilla::DesktopIntRect r = nsCocoaUtils::CocoaRectToGeckoRect(frame);
+
+  *outX = r.x;
+  *outY = r.y;
+  *outWidth = r.width;
+  *outHeight = r.height;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetPixelDepth(int32_t *aPixelDepth)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSWindowDepth depth = [mScreen depth];
+  int bpp = NSBitsPerPixelFromDepth(depth);
+
+  *aPixelDepth = bpp;
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetColorDepth(int32_t *aColorDepth)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSWindowDepth depth = [mScreen depth];
+  int bpp = NSBitsPerPixelFromDepth (depth);
+
+  *aColorDepth = bpp;
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsScreenCocoa::GetContentsScaleFactor(double *aContentsScaleFactor)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  *aContentsScaleFactor = (double) BackingScaleFactor();
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+CGFloat
+nsScreenCocoa::BackingScaleFactor()
+{
+  return nsCocoaUtils::GetBackingScaleFactor(mScreen);
+}
diff --git a/widget/cocoa/nsScreenManagerCocoa.h b/widget/cocoa/nsScreenManagerCocoa.h
new file mode 100644
index 0000000000..61a059d977
--- /dev/null
+++ b/widget/cocoa/nsScreenManagerCocoa.h
@@ -0,0 +1,33 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsScreenManagerCocoa_h_
+#define nsScreenManagerCocoa_h_
+
+#import <Cocoa/Cocoa.h>
+
+#include "mozilla/RefPtr.h"
+#include "nsTArray.h"
+#include "nsIScreenManager.h"
+#include "nsScreenCocoa.h"
+
+class nsScreenManagerCocoa : public nsIScreenManager
+{
+public:
+    nsScreenManagerCocoa();
+
+    NS_DECL_ISUPPORTS
+    NS_DECL_NSISCREENMANAGER
+
+protected:
+    virtual ~nsScreenManagerCocoa();
+
+private:
+
+    nsScreenCocoa *ScreenForCocoaScreen(NSScreen *screen);
+    nsTArray< RefPtr<nsScreenCocoa> > mScreenList;
+};
+
+#endif // nsScreenManagerCocoa_h_
diff --git a/widget/cocoa/nsScreenManagerCocoa.mm b/widget/cocoa/nsScreenManagerCocoa.mm
new file mode 100644
index 0000000000..9a0cbb9cc5
--- /dev/null
+++ b/widget/cocoa/nsScreenManagerCocoa.mm
@@ -0,0 +1,152 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsScreenManagerCocoa.h"
+#include "nsObjCExceptions.h"
+#include "nsCOMPtr.h"
+#include "nsCocoaUtils.h"
+
+using namespace mozilla;
+
+NS_IMPL_ISUPPORTS(nsScreenManagerCocoa, nsIScreenManager)
+
+nsScreenManagerCocoa::nsScreenManagerCocoa()
+{
+}
+
+nsScreenManagerCocoa::~nsScreenManagerCocoa()
+{
+}
+
+nsScreenCocoa*
+nsScreenManagerCocoa::ScreenForCocoaScreen(NSScreen *screen)
+{
+    for (uint32_t i = 0; i < mScreenList.Length(); ++i) {
+        nsScreenCocoa* sc = mScreenList[i];
+        if (sc->CocoaScreen() == screen) {
+            // doesn't addref
+            return sc;
+        }
+    }
+
+    // didn't find it; create and insert
+    RefPtr<nsScreenCocoa> sc = new nsScreenCocoa(screen);
+    mScreenList.AppendElement(sc);
+    return sc.get();
+}
+
+NS_IMETHODIMP
+nsScreenManagerCocoa::ScreenForId (uint32_t aId, nsIScreen **outScreen)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT
+
+    *outScreen = nullptr;
+
+    for (uint32_t i = 0; i < mScreenList.Length(); ++i) {
+        nsScreenCocoa* sc = mScreenList[i];
+        uint32_t id;
+        nsresult rv = sc->GetId(&id);
+
+        if (NS_SUCCEEDED(rv) && id == aId) {
+            *outScreen = sc;
+            NS_ADDREF(*outScreen);
+            return NS_OK;
+        }
+    }
+
+    return NS_ERROR_FAILURE;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsScreenManagerCocoa::ScreenForRect (int32_t aX, int32_t aY,
+                                     int32_t aWidth, int32_t aHeight,
+                                     nsIScreen **outScreen)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    NSEnumerator *screenEnum = [[NSScreen screens] objectEnumerator];
+    NSRect inRect =
+      nsCocoaUtils::GeckoRectToCocoaRect(DesktopIntRect(aX, aY,
+                                                        aWidth, aHeight));
+    NSScreen *screenWindowIsOn = [NSScreen mainScreen];
+    float greatestArea = 0;
+
+    while (NSScreen *screen = [screenEnum nextObject]) {
+        NSDictionary *desc = [screen deviceDescription];
+        if ([desc objectForKey:NSDeviceIsScreen] == nil)
+            continue;
+
+        NSRect r = NSIntersectionRect([screen frame], inRect);
+        float area = r.size.width * r.size.height;
+        if (area > greatestArea) {
+            greatestArea = area;
+            screenWindowIsOn = screen;
+        }
+    }
+
+    *outScreen = ScreenForCocoaScreen(screenWindowIsOn);
+    NS_ADDREF(*outScreen);
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsScreenManagerCocoa::GetPrimaryScreen (nsIScreen **outScreen)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    // the mainScreen is the screen with the "key window" (focus, I assume?)
+    NSScreen *sc = [[NSScreen screens] objectAtIndex:0];
+
+    *outScreen = ScreenForCocoaScreen(sc);
+    NS_ADDREF(*outScreen);
+
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsScreenManagerCocoa::GetNumberOfScreens (uint32_t *aNumberOfScreens)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    NSArray *ss = [NSScreen screens];
+
+    *aNumberOfScreens = [ss count];
+
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsScreenManagerCocoa::GetSystemDefaultScale(float *aDefaultScale)
+{
+    *aDefaultScale = 1.0f;
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsScreenManagerCocoa::ScreenForNativeWidget (void *nativeWidget, nsIScreen **outScreen)
+{
+    NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+    NSWindow *window = static_cast<NSWindow*>(nativeWidget);
+    if (window) {
+        nsIScreen *screen = ScreenForCocoaScreen([window screen]);
+        *outScreen = screen;
+        NS_ADDREF(*outScreen);
+        return NS_OK;
+    }
+
+    *outScreen = nullptr;
+    return NS_OK;
+
+    NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
diff --git a/widget/cocoa/nsSound.h b/widget/cocoa/nsSound.h
new file mode 100644
index 0000000000..0e0293ae28
--- /dev/null
+++ b/widget/cocoa/nsSound.h
@@ -0,0 +1,27 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsSound_h_
+#define nsSound_h_
+
+#include "nsISound.h"
+#include "nsIStreamLoader.h"
+
+class nsSound : public nsISound,
+                public nsIStreamLoaderObserver
+{
+public: 
+    nsSound();
+
+    NS_DECL_ISUPPORTS
+    NS_DECL_NSISOUND
+    NS_DECL_NSISTREAMLOADEROBSERVER
+
+protected:
+    virtual ~nsSound();
+};
+
+#endif // nsSound_h_
diff --git a/widget/cocoa/nsSound.mm b/widget/cocoa/nsSound.mm
new file mode 100644
index 0000000000..04c6b4d764
--- /dev/null
+++ b/widget/cocoa/nsSound.mm
@@ -0,0 +1,108 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsSound.h"
+#include "nsContentUtils.h"
+#include "nsObjCExceptions.h"
+#include "nsNetUtil.h"
+#include "nsCOMPtr.h"
+#include "nsIURL.h"
+#include "nsString.h"
+
+#import <Cocoa/Cocoa.h>
+
+NS_IMPL_ISUPPORTS(nsSound, nsISound, nsIStreamLoaderObserver)
+
+nsSound::nsSound()
+{
+}
+
+nsSound::~nsSound()
+{
+}
+
+NS_IMETHODIMP
+nsSound::Beep()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSBeep();
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsSound::OnStreamComplete(nsIStreamLoader *aLoader,
+                          nsISupports *context,
+                          nsresult aStatus,
+                          uint32_t dataLen,
+                          const uint8_t *data)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  NSData *value = [NSData dataWithBytes:data length:dataLen];
+
+  NSSound *sound = [[NSSound alloc] initWithData:value];
+
+  [sound play];
+
+  [sound autorelease];
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsSound::Play(nsIURL *aURL)
+{
+  nsCOMPtr<nsIURI> uri(do_QueryInterface(aURL));
+  nsCOMPtr<nsIStreamLoader> loader;
+  return NS_NewStreamLoader(getter_AddRefs(loader),
+                            uri,
+                            this, // aObserver
+                            nsContentUtils::GetSystemPrincipal(),
+                            nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_DATA_IS_NULL,
+                            nsIContentPolicy::TYPE_OTHER);
+}
+
+NS_IMETHODIMP
+nsSound::Init()
+{
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSound::PlaySystemSound(const nsAString &aSoundAlias)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  if (NS_IsMozAliasSound(aSoundAlias)) {
+    NS_WARNING("nsISound::playSystemSound is called with \"_moz_\" events, they are obsolete, use nsISound::playEventSound instead");
+    // Mac doesn't have system sound settings for each user actions.
+    return NS_OK;
+  }
+
+  NSString *name = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(aSoundAlias.BeginReading())
+                                           length:aSoundAlias.Length()];
+  NSSound *sound = [NSSound soundNamed:name];
+  if (sound) {
+    [sound stop];
+    [sound play];
+  }
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsSound::PlayEventSound(uint32_t aEventId)
+{
+  // Mac doesn't have system sound settings for each user actions.
+  return NS_OK;
+}
diff --git a/widget/cocoa/nsStandaloneNativeMenu.h b/widget/cocoa/nsStandaloneNativeMenu.h
new file mode 100644
index 0000000000..e03742b1e0
--- /dev/null
+++ b/widget/cocoa/nsStandaloneNativeMenu.h
@@ -0,0 +1,40 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsStandaloneNativeMenu_h_
+#define nsStandaloneNativeMenu_h_
+
+#include "nsMenuGroupOwnerX.h"
+#include "nsMenuX.h"
+#include "nsIStandaloneNativeMenu.h"
+
+class nsStandaloneNativeMenu : public nsMenuGroupOwnerX, public nsIStandaloneNativeMenu
+{
+public:
+  nsStandaloneNativeMenu();
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_NSISTANDALONENATIVEMENU
+
+  // nsMenuObjectX
+  nsMenuObjectTypeX MenuObjectType() override { return eStandaloneNativeMenuObjectType; }
+  void * NativeData() override { return mMenu != nullptr ? mMenu->NativeData() : nullptr; }
+  virtual void IconUpdated() override;
+
+  nsMenuX * GetMenuXObject() { return mMenu; }
+
+  // If this menu is the menu of a system status bar item (NSStatusItem),
+  // let the menu know about the status item so that it can propagate
+  // any icon changes to the status item.
+  void SetContainerStatusBarItem(NSStatusItem* aItem);
+
+protected:
+  virtual ~nsStandaloneNativeMenu();
+
+  nsMenuX * mMenu;
+  NSStatusItem* mContainerStatusBarItem;
+};
+
+#endif
diff --git a/widget/cocoa/nsStandaloneNativeMenu.mm b/widget/cocoa/nsStandaloneNativeMenu.mm
new file mode 100644
index 0000000000..98a5fd8f6f
--- /dev/null
+++ b/widget/cocoa/nsStandaloneNativeMenu.mm
@@ -0,0 +1,213 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsStandaloneNativeMenu.h"
+#include "nsMenuUtilsX.h"
+#include "nsIDOMElement.h"
+#include "nsIMutationObserver.h"
+#include "nsGkAtoms.h"
+#include "nsObjCExceptions.h"
+
+
+NS_IMPL_ISUPPORTS_INHERITED(nsStandaloneNativeMenu, nsMenuGroupOwnerX,
+                            nsIMutationObserver, nsIStandaloneNativeMenu)
+
+nsStandaloneNativeMenu::nsStandaloneNativeMenu()
+: mMenu(nullptr)
+, mContainerStatusBarItem(nil)
+{
+}
+
+nsStandaloneNativeMenu::~nsStandaloneNativeMenu()
+{
+  if (mMenu) delete mMenu;
+}
+
+NS_IMETHODIMP
+nsStandaloneNativeMenu::Init(nsIDOMElement * aDOMElement)
+{
+  NS_ASSERTION(mMenu == nullptr, "nsNativeMenu::Init - mMenu not null!");
+
+  nsresult rv;
+
+  nsCOMPtr<nsIContent> content = do_QueryInterface(aDOMElement, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  if (!content->IsAnyOfXULElements(nsGkAtoms::menu, nsGkAtoms::menupopup))
+    return NS_ERROR_FAILURE;
+
+  rv = nsMenuGroupOwnerX::Create(content);
+  if (NS_FAILED(rv))
+    return rv;
+
+  mMenu = new nsMenuX();
+  rv = mMenu->Create(this, this, content);
+  if (NS_FAILED(rv)) {
+    delete mMenu;
+    mMenu = nullptr;
+    return rv;
+  }
+
+  mMenu->SetupIcon();
+
+  return NS_OK;
+}
+
+static void
+UpdateMenu(nsMenuX * aMenu)
+{
+  aMenu->MenuOpened();
+  aMenu->MenuClosed();
+
+  uint32_t itemCount = aMenu->GetItemCount();
+  for (uint32_t i = 0; i < itemCount; i++) {
+    nsMenuObjectX * menuObject = aMenu->GetItemAt(i);
+    if (menuObject->MenuObjectType() == eSubmenuObjectType) {
+      UpdateMenu(static_cast<nsMenuX*>(menuObject));
+    }
+  }
+}
+
+NS_IMETHODIMP
+nsStandaloneNativeMenu::MenuWillOpen(bool * aResult)
+{
+  NS_ASSERTION(mMenu != nullptr, "nsStandaloneNativeMenu::OnOpen - mMenu is null!");
+
+  // Force an update on the mMenu by faking an open/close on all of
+  // its submenus.
+  UpdateMenu(mMenu);
+
+  *aResult = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsStandaloneNativeMenu::GetNativeMenu(void ** aVoidPointer)
+{
+  if (mMenu) {
+    *aVoidPointer = mMenu->NativeData();
+    [[(NSObject *)(*aVoidPointer) retain] autorelease];
+    return NS_OK;
+  }  else {
+    *aVoidPointer = nullptr;
+    return NS_ERROR_NOT_INITIALIZED;
+  }
+}
+
+static NSMenuItem *
+NativeMenuItemWithLocation(NSMenu * currentSubmenu, NSString * locationString)
+{
+  NSArray * indexes = [locationString componentsSeparatedByString:@"|"];
+  NSUInteger indexCount = [indexes count];
+  if (indexCount == 0)
+    return nil;
+
+  for (NSUInteger i = 0; i < indexCount; i++) {
+    NSInteger targetIndex = [[indexes objectAtIndex:i] integerValue];
+    NSInteger itemCount = [currentSubmenu numberOfItems];
+    if (targetIndex < itemCount) {
+      NSMenuItem* menuItem = [currentSubmenu itemAtIndex:targetIndex];
+
+      // If this is the last index, just return the menu item.
+      if (i == (indexCount - 1))
+        return menuItem;
+
+      // If this is not the last index, find the submenu and keep going.
+      if ([menuItem hasSubmenu])
+        currentSubmenu = [menuItem submenu];
+      else
+        return nil;
+    }
+  }
+
+  return nil;
+}
+
+NS_IMETHODIMP
+nsStandaloneNativeMenu::ActivateNativeMenuItemAt(const nsAString& indexString)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+  
+  if (!mMenu)
+    return NS_ERROR_NOT_INITIALIZED;
+
+  NSString * locationString = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(indexString.BeginReading())
+                                                      length:indexString.Length()];
+  NSMenu * menu = static_cast<NSMenu *> (mMenu->NativeData());
+  NSMenuItem * item = NativeMenuItemWithLocation(menu, locationString);
+
+  // We can't perform an action on an item with a submenu, that will raise
+  // an obj-c exception.
+  if (item && ![item hasSubmenu]) {
+    NSMenu * parent = [item menu];
+    if (parent) {
+      // NSLog(@"Performing action for native menu item titled: %@\n",
+      //       [[currentSubmenu itemAtIndex:targetIndex] title]);
+      [parent performActionForItemAtIndex:[parent indexOfItem:item]];
+      return NS_OK;
+    }
+  }
+
+  return NS_ERROR_FAILURE;
+  
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsStandaloneNativeMenu::ForceUpdateNativeMenuAt(const nsAString& indexString)
+{
+  if (!mMenu)
+    return NS_ERROR_NOT_INITIALIZED;
+
+  NSString* locationString = [NSString stringWithCharacters:reinterpret_cast<const unichar*>(indexString.BeginReading())
+                                                     length:indexString.Length()];
+  NSArray* indexes = [locationString componentsSeparatedByString:@"|"];
+  unsigned int indexCount = [indexes count];
+  if (indexCount == 0)
+    return NS_OK;
+
+  nsMenuX* currentMenu = mMenu;
+
+  // now find the correct submenu
+  for (unsigned int i = 1; currentMenu && i < indexCount; i++) {
+    int targetIndex = [[indexes objectAtIndex:i] intValue];
+    int visible = 0;
+    uint32_t length = currentMenu->GetItemCount();
+    for (unsigned int j = 0; j < length; j++) {
+      nsMenuObjectX* targetMenu = currentMenu->GetItemAt(j);
+      if (!targetMenu)
+        return NS_OK;
+      if (!nsMenuUtilsX::NodeIsHiddenOrCollapsed(targetMenu->Content())) {
+        visible++;
+        if (targetMenu->MenuObjectType() == eSubmenuObjectType && visible == (targetIndex + 1)) {
+          currentMenu = static_cast<nsMenuX*>(targetMenu);
+          // fake open/close to cause lazy update to happen
+          currentMenu->MenuOpened();
+          currentMenu->MenuClosed();
+          break;
+        }
+      }
+    }
+  }
+
+  return NS_OK;
+}
+
+void
+nsStandaloneNativeMenu::IconUpdated()
+{
+  if (mContainerStatusBarItem) {
+    [mContainerStatusBarItem setImage:[mMenu->NativeMenuItem() image]];
+  }
+}
+
+void
+nsStandaloneNativeMenu::SetContainerStatusBarItem(NSStatusItem* aItem)
+{
+  mContainerStatusBarItem = aItem;
+  IconUpdated();
+}
diff --git a/widget/cocoa/nsSystemStatusBarCocoa.h b/widget/cocoa/nsSystemStatusBarCocoa.h
new file mode 100644
index 0000000000..51aa4df00d
--- /dev/null
+++ b/widget/cocoa/nsSystemStatusBarCocoa.h
@@ -0,0 +1,40 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsSystemStatusBarCocoa_h_
+#define nsSystemStatusBarCocoa_h_
+
+#include "mozilla/RefPtr.h"
+#include "nsISystemStatusBar.h"
+#include "nsClassHashtable.h"
+
+class nsStandaloneNativeMenu;
+@class NSStatusItem;
+
+class nsSystemStatusBarCocoa : public nsISystemStatusBar
+{
+public:
+  nsSystemStatusBarCocoa() {}
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSISYSTEMSTATUSBAR
+
+protected:
+  virtual ~nsSystemStatusBarCocoa() {}
+
+  struct StatusItem
+  {
+    explicit StatusItem(nsStandaloneNativeMenu* aMenu);
+    ~StatusItem();
+
+  private:
+    RefPtr<nsStandaloneNativeMenu> mMenu;
+    NSStatusItem* mStatusItem;
+  };
+
+  nsClassHashtable<nsISupportsHashKey, StatusItem> mItems;
+};
+
+#endif // nsSystemStatusBarCocoa_h_
diff --git a/widget/cocoa/nsSystemStatusBarCocoa.mm b/widget/cocoa/nsSystemStatusBarCocoa.mm
new file mode 100644
index 0000000000..522da71451
--- /dev/null
+++ b/widget/cocoa/nsSystemStatusBarCocoa.mm
@@ -0,0 +1,74 @@
+/* -*- Mode: c++; tab-width: 2; indent-tabs-mode: nil; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <Cocoa/Cocoa.h>
+
+#include "nsComponentManagerUtils.h"
+#include "nsSystemStatusBarCocoa.h"
+#include "nsStandaloneNativeMenu.h"
+#include "nsObjCExceptions.h"
+#include "nsIDOMElement.h"
+
+NS_IMPL_ISUPPORTS(nsSystemStatusBarCocoa, nsISystemStatusBar)
+
+NS_IMETHODIMP
+nsSystemStatusBarCocoa::AddItem(nsIDOMElement* aDOMElement)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  RefPtr<nsStandaloneNativeMenu> menu = new nsStandaloneNativeMenu();
+  nsresult rv = menu->Init(aDOMElement);
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+
+  nsCOMPtr<nsISupports> keyPtr = aDOMElement;
+  mItems.Put(keyPtr, new StatusItem(menu));
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+NS_IMETHODIMP
+nsSystemStatusBarCocoa::RemoveItem(nsIDOMElement* aDOMElement)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  mItems.Remove(aDOMElement);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+nsSystemStatusBarCocoa::StatusItem::StatusItem(nsStandaloneNativeMenu* aMenu)
+  : mMenu(aMenu)
+{
+  MOZ_COUNT_CTOR(nsSystemStatusBarCocoa::StatusItem);
+
+  NSMenu* nativeMenu = nil;
+  mMenu->GetNativeMenu(reinterpret_cast<void**>(&nativeMenu));
+
+  mStatusItem = [[[NSStatusBar systemStatusBar] statusItemWithLength:NSSquareStatusItemLength] retain];
+  [mStatusItem setMenu:nativeMenu];
+  [mStatusItem setHighlightMode:YES];
+
+  // We want the status item to get its image from menu item that mMenu was
+  // initialized with. Icon loads are asynchronous, so we need to let the menu
+  // know about the item so that it can update its icon as soon as it has
+  // loaded.
+  mMenu->SetContainerStatusBarItem(mStatusItem);
+}
+
+nsSystemStatusBarCocoa::StatusItem::~StatusItem()
+{
+  mMenu->SetContainerStatusBarItem(nil);
+  [[NSStatusBar systemStatusBar] removeStatusItem:mStatusItem];
+  [mStatusItem release];
+  mStatusItem = nil;
+
+  MOZ_COUNT_DTOR(nsSystemStatusBarCocoa::StatusItem);
+}
diff --git a/widget/cocoa/nsToolkit.h b/widget/cocoa/nsToolkit.h
new file mode 100644
index 0000000000..1631a8ac24
--- /dev/null
+++ b/widget/cocoa/nsToolkit.h
@@ -0,0 +1,53 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsToolkit_h_
+#define nsToolkit_h_
+
+#include "nscore.h"
+
+#import <Carbon/Carbon.h>
+#import <Cocoa/Cocoa.h>
+#import <objc/Object.h>
+#import <IOKit/IOKitLib.h>
+
+class nsToolkit
+{
+public:
+                     nsToolkit();
+  virtual            ~nsToolkit();
+
+  static nsToolkit*  GetToolkit();
+
+  static void Shutdown() {
+    delete gToolkit;
+    gToolkit = nullptr;
+  }
+
+  static void        PostSleepWakeNotification(const char* aNotification);
+
+  static nsresult    SwizzleMethods(Class aClass, SEL orgMethod, SEL posedMethod,
+                                    bool classMethods = false);
+
+  void               RegisterForAllProcessMouseEvents();
+  void               UnregisterAllProcessMouseEventHandlers();
+
+protected:
+
+  nsresult           RegisterForSleepWakeNotifications();
+  void               RemoveSleepWakeNotifications();
+
+protected:
+
+  static nsToolkit*  gToolkit;
+
+  CFRunLoopSourceRef mSleepWakeNotificationRLS;
+  io_object_t        mPowerNotifier;
+
+  CFMachPortRef      mEventTapPort;
+  CFRunLoopSourceRef mEventTapRLS;
+};
+
+#endif // nsToolkit_h_
diff --git a/widget/cocoa/nsToolkit.mm b/widget/cocoa/nsToolkit.mm
new file mode 100644
index 0000000000..4d0222d5d3
--- /dev/null
+++ b/widget/cocoa/nsToolkit.mm
@@ -0,0 +1,326 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsToolkit.h"
+
+#include <ctype.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <mach/mach_port.h>
+#include <mach/mach_interface.h>
+#include <mach/mach_init.h>
+
+extern "C" {
+#include <mach-o/getsect.h>
+}
+#include <unistd.h>
+#include <dlfcn.h>
+
+#import <Cocoa/Cocoa.h>
+#import <IOKit/pwr_mgt/IOPMLib.h>
+#import <IOKit/IOMessage.h>
+
+#include "nsCocoaUtils.h"
+#include "nsObjCExceptions.h"
+
+#include "nsGkAtoms.h"
+#include "nsIRollupListener.h"
+#include "nsIWidget.h"
+#include "nsBaseWidget.h"
+
+#include "nsIObserverService.h"
+#include "nsIServiceManager.h"
+
+#include "mozilla/Preferences.h"
+#include "mozilla/Services.h"
+
+using namespace mozilla;
+
+static io_connect_t gRootPort = MACH_PORT_NULL;
+
+nsToolkit* nsToolkit::gToolkit = nullptr;
+
+nsToolkit::nsToolkit()
+: mSleepWakeNotificationRLS(nullptr)
+, mEventTapPort(nullptr)
+, mEventTapRLS(nullptr)
+{
+  MOZ_COUNT_CTOR(nsToolkit);
+  RegisterForSleepWakeNotifications();
+}
+
+nsToolkit::~nsToolkit()
+{
+  MOZ_COUNT_DTOR(nsToolkit);
+  RemoveSleepWakeNotifications();
+  UnregisterAllProcessMouseEventHandlers();
+}
+
+void
+nsToolkit::PostSleepWakeNotification(const char* aNotification)
+{
+  nsCOMPtr<nsIObserverService> observerService = services::GetObserverService();
+  if (observerService)
+    observerService->NotifyObservers(nullptr, aNotification, nullptr);
+}
+
+// http://developer.apple.com/documentation/DeviceDrivers/Conceptual/IOKitFundamentals/PowerMgmt/chapter_10_section_3.html
+static void ToolkitSleepWakeCallback(void *refCon, io_service_t service, natural_t messageType, void * messageArgument)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  switch (messageType)
+  {
+    case kIOMessageSystemWillSleep:
+      // System is going to sleep now.
+      nsToolkit::PostSleepWakeNotification(NS_WIDGET_SLEEP_OBSERVER_TOPIC);
+      ::IOAllowPowerChange(gRootPort, (long)messageArgument);
+      break;
+      
+    case kIOMessageCanSystemSleep:
+      // In this case, the computer has been idle for several minutes
+      // and will sleep soon so you must either allow or cancel
+      // this notification. Important: if you don’t respond, there will
+      // be a 30-second timeout before the computer sleeps.
+      // In Mozilla's case, we always allow sleep.
+      ::IOAllowPowerChange(gRootPort,(long)messageArgument);
+      break;
+      
+    case kIOMessageSystemHasPoweredOn:
+      // Handle wakeup.
+      nsToolkit::PostSleepWakeNotification(NS_WIDGET_WAKE_OBSERVER_TOPIC);
+      break;
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+nsresult
+nsToolkit::RegisterForSleepWakeNotifications()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  IONotificationPortRef notifyPortRef;
+
+  NS_ASSERTION(!mSleepWakeNotificationRLS, "Already registered for sleep/wake");
+
+  gRootPort = ::IORegisterForSystemPower(0, &notifyPortRef, ToolkitSleepWakeCallback, &mPowerNotifier);
+  if (gRootPort == MACH_PORT_NULL) {
+    NS_ERROR("IORegisterForSystemPower failed");
+    return NS_ERROR_FAILURE;
+  }
+
+  mSleepWakeNotificationRLS = ::IONotificationPortGetRunLoopSource(notifyPortRef);
+  ::CFRunLoopAddSource(::CFRunLoopGetCurrent(),
+                       mSleepWakeNotificationRLS,
+                       kCFRunLoopDefaultMode);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
+
+void
+nsToolkit::RemoveSleepWakeNotifications()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mSleepWakeNotificationRLS) {
+    ::IODeregisterForSystemPower(&mPowerNotifier);
+    ::CFRunLoopRemoveSource(::CFRunLoopGetCurrent(),
+                            mSleepWakeNotificationRLS,
+                            kCFRunLoopDefaultMode);
+
+    mSleepWakeNotificationRLS = nullptr;
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Converts aPoint from the CoreGraphics "global display coordinate" system
+// (which includes all displays/screens and has a top-left origin) to its
+// (presumed) Cocoa counterpart (assumed to be the same as the "screen
+// coordinates" system), which has a bottom-left origin.
+static NSPoint ConvertCGGlobalToCocoaScreen(CGPoint aPoint)
+{
+  NSPoint cocoaPoint;
+  cocoaPoint.x = aPoint.x;
+  cocoaPoint.y = nsCocoaUtils::FlippedScreenY(aPoint.y);
+  return cocoaPoint;
+}
+
+// Since our event tap is "listen only", events arrive here a little after
+// they've already been processed.
+static CGEventRef EventTapCallback(CGEventTapProxy proxy, CGEventType type, CGEventRef event, void *refcon)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if ((type == kCGEventTapDisabledByUserInput) ||
+      (type == kCGEventTapDisabledByTimeout))
+    return event;
+  if ([NSApp isActive])
+    return event;
+
+  nsIRollupListener* rollupListener = nsBaseWidget::GetActiveRollupListener();
+  NS_ENSURE_TRUE(rollupListener, event);
+  nsCOMPtr<nsIWidget> rollupWidget = rollupListener->GetRollupWidget();
+  if (!rollupWidget)
+    return event;
+
+  // Don't bother with rightMouseDown events here -- because of the delay,
+  // we'll end up closing browser context menus that we just opened.  Since
+  // these events usually raise a context menu, we'll handle them by hooking
+  // the @"com.apple.HIToolbox.beginMenuTrackingNotification" distributed
+  // notification (in nsAppShell.mm's AppShellDelegate).
+  if (type == kCGEventRightMouseDown)
+    return event;
+  NSWindow *ctxMenuWindow = (NSWindow*) rollupWidget->GetNativeData(NS_NATIVE_WINDOW);
+  if (!ctxMenuWindow)
+    return event;
+  NSPoint screenLocation = ConvertCGGlobalToCocoaScreen(CGEventGetLocation(event));
+  // Don't roll up the rollup widget if our mouseDown happens over it (doing
+  // so would break the corresponding context menu).
+  if (NSPointInRect(screenLocation, [ctxMenuWindow frame]))
+    return event;
+  rollupListener->Rollup(0, false, nullptr, nullptr);
+  return event;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NULL);
+}
+
+// Cocoa Firefox's use of custom context menus requires that we explicitly
+// handle mouse events from other processes that the OS handles
+// "automatically" for native context menus -- mouseMoved events so that
+// right-click context menus work properly when our browser doesn't have the
+// focus (bmo bug 368077), and mouseDown events so that our browser can
+// dismiss a context menu when a mouseDown happens in another process (bmo
+// bug 339945).
+void
+nsToolkit::RegisterForAllProcessMouseEvents()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (getenv("MOZ_DEBUG"))
+    return;
+
+  // Don't do this for apps that use native context menus.
+#ifdef MOZ_USE_NATIVE_POPUP_WINDOWS
+  return;
+#endif /* MOZ_USE_NATIVE_POPUP_WINDOWS */
+
+  if (!mEventTapRLS) {
+    // Using an event tap for mouseDown events (instead of installing a
+    // handler for them on the EventMonitor target) works around an Apple
+    // bug that causes OS menus (like the Clock menu) not to work properly
+    // on OS X 10.4.X and below (bmo bug 381448).
+    // We install our event tap "listen only" to get around yet another Apple
+    // bug -- when we install it as an event filter on any kind of mouseDown
+    // event, that kind of event stops working in the main menu, and usually
+    // mouse event processing stops working in all apps in the current login
+    // session (so the entire OS appears to be hung)!  The downside of
+    // installing listen-only is that events arrive at our handler slightly
+    // after they've already been processed.
+    mEventTapPort = CGEventTapCreate(kCGSessionEventTap,
+                                     kCGHeadInsertEventTap,
+                                     kCGEventTapOptionListenOnly,
+                                     CGEventMaskBit(kCGEventLeftMouseDown)
+                                       | CGEventMaskBit(kCGEventRightMouseDown)
+                                       | CGEventMaskBit(kCGEventOtherMouseDown),
+                                     EventTapCallback,
+                                     nullptr);
+    if (!mEventTapPort)
+      return;
+    mEventTapRLS = CFMachPortCreateRunLoopSource(nullptr, mEventTapPort, 0);
+    if (!mEventTapRLS) {
+      CFRelease(mEventTapPort);
+      mEventTapPort = nullptr;
+      return;
+    }
+    CFRunLoopAddSource(CFRunLoopGetCurrent(), mEventTapRLS, kCFRunLoopDefaultMode);
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+void
+nsToolkit::UnregisterAllProcessMouseEventHandlers()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (mEventTapRLS) {
+    CFRunLoopRemoveSource(CFRunLoopGetCurrent(), mEventTapRLS,
+                          kCFRunLoopDefaultMode);
+    CFRelease(mEventTapRLS);
+    mEventTapRLS = nullptr;
+  }
+  if (mEventTapPort) {
+    // mEventTapPort must be invalidated as well as released.  Otherwise the
+    // event tap doesn't get destroyed until the browser process ends (it
+    // keeps showing up in the list returned by CGGetEventTapList()).
+    CFMachPortInvalidate(mEventTapPort);
+    CFRelease(mEventTapPort);
+    mEventTapPort = nullptr;
+  }
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// Return the nsToolkit instance.  If a toolkit does not yet exist, then one
+// will be created.
+// static
+nsToolkit* nsToolkit::GetToolkit()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_RETURN;
+
+  if (!gToolkit) {
+    gToolkit = new nsToolkit();
+  }
+
+  return gToolkit;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(nullptr);
+}
+
+// An alternative to [NSObject poseAsClass:] that isn't deprecated on OS X
+// Leopard and is available to 64-bit binaries on Leopard and above.  Based on
+// ideas and code from http://www.cocoadev.com/index.pl?MethodSwizzling.
+// Since the Method type becomes an opaque type as of Objective-C 2.0, we'll
+// have to switch to using accessor methods like method_exchangeImplementations()
+// when we build 64-bit binaries that use Objective-C 2.0 (on and for Leopard
+// and above).
+//
+// Be aware that, if aClass doesn't have an orgMethod selector but one of its
+// superclasses does, the method substitution will (in effect) take place in
+// that superclass (rather than in aClass itself).  The substitution has
+// effect on the class where it takes place and all of that class's
+// subclasses.  In order for method swizzling to work properly, posedMethod
+// needs to be unique in the class where the substitution takes place and all
+// of its subclasses.
+nsresult nsToolkit::SwizzleMethods(Class aClass, SEL orgMethod, SEL posedMethod,
+                                   bool classMethods)
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
+
+  Method original = nil;
+  Method posed = nil;
+
+  if (classMethods) {
+    original = class_getClassMethod(aClass, orgMethod);
+    posed = class_getClassMethod(aClass, posedMethod);
+  } else {
+    original = class_getInstanceMethod(aClass, orgMethod);
+    posed = class_getInstanceMethod(aClass, posedMethod);
+  }
+
+  if (!original || !posed)
+    return NS_ERROR_FAILURE;
+
+  method_exchangeImplementations(original, posed);
+
+  return NS_OK;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
+}
diff --git a/widget/cocoa/nsWidgetFactory.mm b/widget/cocoa/nsWidgetFactory.mm
new file mode 100644
index 0000000000..3bddaf95ce
--- /dev/null
+++ b/widget/cocoa/nsWidgetFactory.mm
@@ -0,0 +1,219 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIFactory.h"
+#include "nsISupports.h"
+#include "nsIComponentManager.h"
+#include "mozilla/ModuleUtils.h"
+#include "mozilla/WidgetUtils.h"
+
+#include "nsWidgetsCID.h"
+
+#include "nsChildView.h"
+#include "nsCocoaWindow.h"
+#include "nsAppShell.h"
+#include "nsAppShellSingleton.h"
+#include "nsFilePicker.h"
+#include "nsColorPicker.h"
+
+#include "nsClipboard.h"
+#include "nsClipboardHelper.h"
+#include "nsTransferable.h"
+#include "nsHTMLFormatConverter.h"
+#include "nsDragService.h"
+#include "nsToolkit.h"
+
+#include "nsLookAndFeel.h"
+
+#include "nsSound.h"
+#include "nsIdleServiceX.h"
+#include "NativeKeyBindings.h"
+#include "OSXNotificationCenter.h"
+
+#include "nsScreenManagerCocoa.h"
+#include "nsDeviceContextSpecX.h"
+#include "nsPrintOptionsX.h"
+#include "nsPrintDialogX.h"
+#include "nsPrintSession.h"
+#include "nsToolkitCompsCID.h"
+
+using namespace mozilla;
+using namespace mozilla::widget;
+
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsCocoaWindow)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsChildView)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsFilePicker)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsColorPicker)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsSound)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsTransferable)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsHTMLFormatConverter)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsClipboard)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsClipboardHelper)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsDragService)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsScreenManagerCocoa)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsDeviceContextSpecX)
+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsPrintOptionsX, Init)
+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsPrintDialogServiceX, Init)
+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsPrintSession, Init)
+NS_GENERIC_FACTORY_SINGLETON_CONSTRUCTOR(nsIdleServiceX, nsIdleServiceX::GetInstance)
+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(OSXNotificationCenter, Init)
+
+#include "nsMenuBarX.h"
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsNativeMenuServiceX)
+
+#include "nsBidiKeyboard.h"
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsBidiKeyboard)
+
+#include "nsNativeThemeCocoa.h"
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsNativeThemeCocoa)
+
+#include "nsMacDockSupport.h"
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsMacDockSupport)
+
+#include "nsMacWebAppUtils.h"
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsMacWebAppUtils)
+
+#include "nsStandaloneNativeMenu.h"
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsStandaloneNativeMenu)
+
+#include "nsSystemStatusBarCocoa.h"
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsSystemStatusBarCocoa)
+
+#include "GfxInfo.h"
+namespace mozilla {
+namespace widget {
+// This constructor should really be shared with all platforms.
+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(GfxInfo, Init)
+} // namespace widget
+} // namespace mozilla
+
+NS_DEFINE_NAMED_CID(NS_WINDOW_CID);
+NS_DEFINE_NAMED_CID(NS_POPUP_CID);
+NS_DEFINE_NAMED_CID(NS_CHILD_CID);
+NS_DEFINE_NAMED_CID(NS_FILEPICKER_CID);
+NS_DEFINE_NAMED_CID(NS_COLORPICKER_CID);
+NS_DEFINE_NAMED_CID(NS_APPSHELL_CID);
+NS_DEFINE_NAMED_CID(NS_SOUND_CID);
+NS_DEFINE_NAMED_CID(NS_TRANSFERABLE_CID);
+NS_DEFINE_NAMED_CID(NS_HTMLFORMATCONVERTER_CID);
+NS_DEFINE_NAMED_CID(NS_CLIPBOARD_CID);
+NS_DEFINE_NAMED_CID(NS_CLIPBOARDHELPER_CID);
+NS_DEFINE_NAMED_CID(NS_DRAGSERVICE_CID);
+NS_DEFINE_NAMED_CID(NS_BIDIKEYBOARD_CID);
+NS_DEFINE_NAMED_CID(NS_THEMERENDERER_CID);
+NS_DEFINE_NAMED_CID(NS_SCREENMANAGER_CID);
+NS_DEFINE_NAMED_CID(NS_DEVICE_CONTEXT_SPEC_CID);
+NS_DEFINE_NAMED_CID(NS_PRINTSESSION_CID);
+NS_DEFINE_NAMED_CID(NS_PRINTSETTINGSSERVICE_CID);
+NS_DEFINE_NAMED_CID(NS_PRINTDIALOGSERVICE_CID);
+NS_DEFINE_NAMED_CID(NS_IDLE_SERVICE_CID);
+NS_DEFINE_NAMED_CID(NS_SYSTEMALERTSSERVICE_CID);
+NS_DEFINE_NAMED_CID(NS_NATIVEMENUSERVICE_CID);
+NS_DEFINE_NAMED_CID(NS_MACDOCKSUPPORT_CID);
+NS_DEFINE_NAMED_CID(NS_MACWEBAPPUTILS_CID);
+NS_DEFINE_NAMED_CID(NS_STANDALONENATIVEMENU_CID);
+NS_DEFINE_NAMED_CID(NS_MACSYSTEMSTATUSBAR_CID);
+NS_DEFINE_NAMED_CID(NS_GFXINFO_CID);
+
+static const mozilla::Module::CIDEntry kWidgetCIDs[] = {
+  { &kNS_WINDOW_CID, false, NULL, nsCocoaWindowConstructor },
+  { &kNS_POPUP_CID, false, NULL, nsCocoaWindowConstructor },
+  { &kNS_CHILD_CID, false, NULL, nsChildViewConstructor },
+  { &kNS_FILEPICKER_CID, false, NULL, nsFilePickerConstructor,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { &kNS_COLORPICKER_CID, false, NULL, nsColorPickerConstructor,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { &kNS_APPSHELL_CID, false, NULL, nsAppShellConstructor, mozilla::Module::ALLOW_IN_GPU_PROCESS },
+  { &kNS_SOUND_CID, false, NULL, nsSoundConstructor,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { &kNS_TRANSFERABLE_CID, false, NULL, nsTransferableConstructor },
+  { &kNS_HTMLFORMATCONVERTER_CID, false, NULL, nsHTMLFormatConverterConstructor },
+  { &kNS_CLIPBOARD_CID, false, NULL, nsClipboardConstructor,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { &kNS_CLIPBOARDHELPER_CID, false, NULL, nsClipboardHelperConstructor },
+  { &kNS_DRAGSERVICE_CID, false, NULL, nsDragServiceConstructor,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { &kNS_BIDIKEYBOARD_CID, false, NULL, nsBidiKeyboardConstructor,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { &kNS_THEMERENDERER_CID, false, NULL, nsNativeThemeCocoaConstructor },
+  { &kNS_SCREENMANAGER_CID, false, NULL, nsScreenManagerCocoaConstructor,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { &kNS_DEVICE_CONTEXT_SPEC_CID, false, NULL, nsDeviceContextSpecXConstructor },
+  { &kNS_PRINTSESSION_CID, false, NULL, nsPrintSessionConstructor },
+  { &kNS_PRINTSETTINGSSERVICE_CID, false, NULL, nsPrintOptionsXConstructor },
+  { &kNS_PRINTDIALOGSERVICE_CID, false, NULL, nsPrintDialogServiceXConstructor },
+  { &kNS_IDLE_SERVICE_CID, false, NULL, nsIdleServiceXConstructor },
+  { &kNS_SYSTEMALERTSSERVICE_CID, false, NULL, OSXNotificationCenterConstructor },
+  { &kNS_NATIVEMENUSERVICE_CID, false, NULL, nsNativeMenuServiceXConstructor },
+  { &kNS_MACDOCKSUPPORT_CID, false, NULL, nsMacDockSupportConstructor },
+  { &kNS_MACWEBAPPUTILS_CID, false, NULL, nsMacWebAppUtilsConstructor },
+  { &kNS_STANDALONENATIVEMENU_CID, false, NULL, nsStandaloneNativeMenuConstructor },
+  { &kNS_MACSYSTEMSTATUSBAR_CID, false, NULL, nsSystemStatusBarCocoaConstructor },
+  { &kNS_GFXINFO_CID, false, NULL, mozilla::widget::GfxInfoConstructor },
+  { NULL }
+};
+
+static const mozilla::Module::ContractIDEntry kWidgetContracts[] = {
+  { "@mozilla.org/widgets/window/mac;1", &kNS_WINDOW_CID },
+  { "@mozilla.org/widgets/popup/mac;1", &kNS_POPUP_CID },
+  { "@mozilla.org/widgets/childwindow/mac;1", &kNS_CHILD_CID },
+  { "@mozilla.org/filepicker;1", &kNS_FILEPICKER_CID,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { "@mozilla.org/colorpicker;1", &kNS_COLORPICKER_CID,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { "@mozilla.org/widget/appshell/mac;1", &kNS_APPSHELL_CID, mozilla::Module::ALLOW_IN_GPU_PROCESS },
+  { "@mozilla.org/sound;1", &kNS_SOUND_CID,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { "@mozilla.org/widget/transferable;1", &kNS_TRANSFERABLE_CID },
+  { "@mozilla.org/widget/htmlformatconverter;1", &kNS_HTMLFORMATCONVERTER_CID },
+  { "@mozilla.org/widget/clipboard;1", &kNS_CLIPBOARD_CID,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { "@mozilla.org/widget/clipboardhelper;1", &kNS_CLIPBOARDHELPER_CID },
+  { "@mozilla.org/widget/dragservice;1", &kNS_DRAGSERVICE_CID,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { "@mozilla.org/widget/bidikeyboard;1", &kNS_BIDIKEYBOARD_CID,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { "@mozilla.org/chrome/chrome-native-theme;1", &kNS_THEMERENDERER_CID },
+  { "@mozilla.org/gfx/screenmanager;1", &kNS_SCREENMANAGER_CID,
+    mozilla::Module::MAIN_PROCESS_ONLY },
+  { "@mozilla.org/gfx/devicecontextspec;1", &kNS_DEVICE_CONTEXT_SPEC_CID },
+  { "@mozilla.org/gfx/printsession;1", &kNS_PRINTSESSION_CID },
+  { "@mozilla.org/gfx/printsettings-service;1", &kNS_PRINTSETTINGSSERVICE_CID },
+  { NS_PRINTDIALOGSERVICE_CONTRACTID, &kNS_PRINTDIALOGSERVICE_CID },
+  { "@mozilla.org/widget/idleservice;1", &kNS_IDLE_SERVICE_CID },
+  { "@mozilla.org/system-alerts-service;1", &kNS_SYSTEMALERTSSERVICE_CID },
+  { "@mozilla.org/widget/nativemenuservice;1", &kNS_NATIVEMENUSERVICE_CID },
+  { "@mozilla.org/widget/macdocksupport;1", &kNS_MACDOCKSUPPORT_CID },
+  { "@mozilla.org/widget/mac-web-app-utils;1", &kNS_MACWEBAPPUTILS_CID },
+  { "@mozilla.org/widget/standalonenativemenu;1", &kNS_STANDALONENATIVEMENU_CID },
+  { "@mozilla.org/widget/macsystemstatusbar;1", &kNS_MACSYSTEMSTATUSBAR_CID },
+  { "@mozilla.org/gfx/info;1", &kNS_GFXINFO_CID },
+  { NULL }
+};
+
+static void
+nsWidgetCocoaModuleDtor()
+{
+  // Shutdown all XP level widget classes.
+  WidgetUtils::Shutdown();
+
+  NativeKeyBindings::Shutdown();
+  nsLookAndFeel::Shutdown();
+  nsToolkit::Shutdown();
+  nsAppShellShutdown();
+}
+
+static const mozilla::Module kWidgetModule = {
+  mozilla::Module::kVersion,
+  kWidgetCIDs,
+  kWidgetContracts,
+  NULL,
+  NULL,
+  nsAppShellInit,
+  nsWidgetCocoaModuleDtor,
+  mozilla::Module::ALLOW_IN_GPU_PROCESS
+};
+
+NSMODULE_DEFN(nsWidgetMacModule) = &kWidgetModule;
diff --git a/widget/cocoa/nsWindowMap.h b/widget/cocoa/nsWindowMap.h
new file mode 100644
index 0000000000..c6ad72c010
--- /dev/null
+++ b/widget/cocoa/nsWindowMap.h
@@ -0,0 +1,62 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsWindowMap_h_
+#define nsWindowMap_h_
+
+#import <Cocoa/Cocoa.h>
+
+//  WindowDataMap
+// 
+//  In both mozilla and embedding apps, we need to have a place to put
+//  per-top-level-window logic and data, to handle such things as IME
+//  commit when the window gains/loses focus. We can't use a window 
+//  delegate, because an embeddor probably already has one. Nor can we
+//  subclass NSWindow, again because we can't impose that burden on the
+//  embeddor.
+// 
+//  So we have a global map of NSWindow -> TopLevelWindowData, and set
+//  up TopLevelWindowData as a notification observer etc.
+
+@interface WindowDataMap : NSObject
+{
+@private
+  NSMutableDictionary*    mWindowMap;   // dict of TopLevelWindowData keyed by address of NSWindow
+}
+
++ (WindowDataMap*)sharedWindowDataMap;
+
+- (void)ensureDataForWindow:(NSWindow*)inWindow;
+- (id)dataForWindow:(NSWindow*)inWindow;
+
+// set data for a given window. inData is retained (and any previously set data
+// is released).
+- (void)setData:(id)inData forWindow:(NSWindow*)inWindow;
+
+// remove the data for the given window. the data is released.
+- (void)removeDataForWindow:(NSWindow*)inWindow;
+
+@end
+
+@class ChildView;
+
+//  TopLevelWindowData
+// 
+//  Class to hold per-window data, and handle window state changes.
+
+@interface TopLevelWindowData : NSObject
+{
+@private
+}
+
+- (id)initWithWindow:(NSWindow*)inWindow;
++ (void)activateInWindow:(NSWindow*)aWindow;
++ (void)deactivateInWindow:(NSWindow*)aWindow;
++ (void)activateInWindowViews:(NSWindow*)aWindow;
++ (void)deactivateInWindowViews:(NSWindow*)aWindow;
+
+@end
+
+#endif // nsWindowMap_h_
diff --git a/widget/cocoa/nsWindowMap.mm b/widget/cocoa/nsWindowMap.mm
new file mode 100644
index 0000000000..c43b024086
--- /dev/null
+++ b/widget/cocoa/nsWindowMap.mm
@@ -0,0 +1,311 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsWindowMap.h"
+#include "nsObjCExceptions.h"
+#include "nsChildView.h"
+#include "nsCocoaWindow.h"
+
+@interface WindowDataMap(Private)
+
+- (NSString*)keyForWindow:(NSWindow*)inWindow;
+
+@end
+
+@interface TopLevelWindowData(Private)
+
+- (void)windowResignedKey:(NSNotification*)inNotification;
+- (void)windowBecameKey:(NSNotification*)inNotification;
+- (void)windowWillClose:(NSNotification*)inNotification;
+
+@end
+
+#pragma mark -
+
+@implementation WindowDataMap
+
++ (WindowDataMap*)sharedWindowDataMap
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  static WindowDataMap* sWindowMap = nil;
+  if (!sWindowMap)
+    sWindowMap = [[WindowDataMap alloc] init];
+
+  return sWindowMap;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (id)init
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if ((self = [super init])) {
+    mWindowMap = [[NSMutableDictionary alloc] initWithCapacity:10];
+  }
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mWindowMap release];
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)ensureDataForWindow:(NSWindow*)inWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!inWindow || [self dataForWindow:inWindow])
+    return;
+
+  TopLevelWindowData* windowData = [[TopLevelWindowData alloc] initWithWindow:inWindow];
+  [self setData:windowData forWindow:inWindow]; // takes ownership
+  [windowData release];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (id)dataForWindow:(NSWindow*)inWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [mWindowMap objectForKey:[self keyForWindow:inWindow]];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)setData:(id)inData forWindow:(NSWindow*)inWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mWindowMap setObject:inData forKey:[self keyForWindow:inWindow]];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (void)removeDataForWindow:(NSWindow*)inWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [mWindowMap removeObjectForKey:[self keyForWindow:inWindow]];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+- (NSString*)keyForWindow:(NSWindow*)inWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  return [NSString stringWithFormat:@"%p", inWindow];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+@end
+
+//  TopLevelWindowData
+// 
+//  This class holds data about top-level windows. We can't use a window
+//  delegate, because an embedder may already have one.
+
+@implementation TopLevelWindowData
+
+- (id)initWithWindow:(NSWindow*)inWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
+
+  if ((self = [super init])) {
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(windowBecameKey:)
+                                                 name:NSWindowDidBecomeKeyNotification
+                                               object:inWindow];
+
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(windowResignedKey:)
+                                                 name:NSWindowDidResignKeyNotification
+                                               object:inWindow];
+
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(windowBecameMain:)
+                                                 name:NSWindowDidBecomeMainNotification
+                                               object:inWindow];
+
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(windowResignedMain:)
+                                                 name:NSWindowDidResignMainNotification
+                                               object:inWindow];
+
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(windowWillClose:)
+                                                 name:NSWindowWillCloseNotification
+                                               object:inWindow];
+  }
+  return self;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_NIL;
+}
+
+- (void)dealloc
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  [super dealloc];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// As best I can tell, if the notification's object has a corresponding
+// top-level widget (an nsCocoaWindow object), it has a delegate (set in
+// nsCocoaWindow::StandardCreate()) of class WindowDelegate, and otherwise
+// not (Camino didn't use top-level widgets (nsCocoaWindow objects) --
+// only child widgets (nsChildView objects)).  (The notification is sent
+// to windowBecameKey: or windowBecameMain: below.)
+//
+// For use with clients that (like Firefox) do use top-level widgets (and
+// have NSWindow delegates of class WindowDelegate).
++ (void)activateInWindow:(NSWindow*)aWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  WindowDelegate* delegate = (WindowDelegate*) [aWindow delegate];
+  if (!delegate || ![delegate isKindOfClass:[WindowDelegate class]])
+    return;
+
+  if ([delegate toplevelActiveState])
+    return;
+  [delegate sendToplevelActivateEvents];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// See comments above activateInWindow:
+//
+// If we're using top-level widgets (nsCocoaWindow objects), we send them
+// NS_DEACTIVATE events (which propagate to child widgets (nsChildView
+// objects) via nsWebShellWindow::HandleEvent()).
+//
+// For use with clients that (like Firefox) do use top-level widgets (and
+// have NSWindow delegates of class WindowDelegate).
++ (void)deactivateInWindow:(NSWindow*)aWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  WindowDelegate* delegate = (WindowDelegate*) [aWindow delegate];
+  if (!delegate || ![delegate isKindOfClass:[WindowDelegate class]])
+    return;
+
+  if (![delegate toplevelActiveState])
+    return;
+  [delegate sendToplevelDeactivateEvents];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// For use with clients that (like Camino) don't use top-level widgets (and
+// don't have NSWindow delegates of class WindowDelegate).
++ (void)activateInWindowViews:(NSWindow*)aWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  id firstResponder = [aWindow firstResponder];
+  if ([firstResponder isKindOfClass:[ChildView class]])
+    [firstResponder viewsWindowDidBecomeKey];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// For use with clients that (like Camino) don't use top-level widgets (and
+// don't have NSWindow delegates of class WindowDelegate).
++ (void)deactivateInWindowViews:(NSWindow*)aWindow
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  id firstResponder = [aWindow firstResponder];
+  if ([firstResponder isKindOfClass:[ChildView class]])
+    [firstResponder viewsWindowDidResignKey];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+// We make certain exceptions for top-level windows in non-embedders (see
+// comment above windowBecameMain below).  And we need (elsewhere) to guard
+// against sending duplicate events.  But in general the NS_ACTIVATE event
+// should be sent when a native window becomes key, and the NS_DEACTIVATE
+// event should be sent when it resignes key.
+- (void)windowBecameKey:(NSNotification*)inNotification
+{
+  NSWindow* window = (NSWindow*)[inNotification object];
+
+  id delegate = [window delegate];
+  if (!delegate || ![delegate isKindOfClass:[WindowDelegate class]]) {
+    [TopLevelWindowData activateInWindowViews:window];
+  } else if ([window isSheet]) {
+    [TopLevelWindowData activateInWindow:window];
+  }
+
+  [[window contentView] setNeedsDisplay:YES];
+}
+
+- (void)windowResignedKey:(NSNotification*)inNotification
+{
+  NSWindow* window = (NSWindow*)[inNotification object];
+
+  id delegate = [window delegate];
+  if (!delegate || ![delegate isKindOfClass:[WindowDelegate class]]) {
+    [TopLevelWindowData deactivateInWindowViews:window];
+  } else if ([window isSheet]) {
+    [TopLevelWindowData deactivateInWindow:window];
+  }
+
+  [[window contentView] setNeedsDisplay:YES];
+}
+
+// The appearance of a top-level window depends on its main state (not its key
+// state).  So (for non-embedders) we need to ensure that a top-level window
+// is main when an NS_ACTIVATE event is sent to Gecko for it.
+- (void)windowBecameMain:(NSNotification*)inNotification
+{
+  NSWindow* window = (NSWindow*)[inNotification object];
+
+  id delegate = [window delegate];
+  // Don't send events to a top-level window that has a sheet open above it --
+  // as far as Gecko is concerned, it's inactive, and stays so until the sheet
+  // closes.
+  if (delegate && [delegate isKindOfClass:[WindowDelegate class]] && ![window attachedSheet])
+    [TopLevelWindowData activateInWindow:window];
+}
+
+- (void)windowResignedMain:(NSNotification*)inNotification
+{
+  NSWindow* window = (NSWindow*)[inNotification object];
+
+  id delegate = [window delegate];
+  if (delegate && [delegate isKindOfClass:[WindowDelegate class]] && ![window attachedSheet])
+    [TopLevelWindowData deactivateInWindow:window];
+}
+
+- (void)windowWillClose:(NSNotification*)inNotification
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // postpone our destruction
+  [[self retain] autorelease];
+
+  // remove ourselves from the window map (which owns us)
+  [[WindowDataMap sharedWindowDataMap] removeDataForWindow:[inNotification object]];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+@end
diff --git a/widget/cocoa/resources/MainMenu.nib/classes.nib b/widget/cocoa/resources/MainMenu.nib/classes.nib
new file mode 100644
index 0000000000..b9b4b09f6b
--- /dev/null
+++ b/widget/cocoa/resources/MainMenu.nib/classes.nib
@@ -0,0 +1,4 @@
+{
+    IBClasses = ({CLASS = FirstResponder; LANGUAGE = ObjC; SUPERCLASS = NSObject; }); 
+    IBVersion = 1; 
+}
\ No newline at end of file
diff --git a/widget/cocoa/resources/MainMenu.nib/info.nib b/widget/cocoa/resources/MainMenu.nib/info.nib
new file mode 100644
index 0000000000..bcf3ace841
--- /dev/null
+++ b/widget/cocoa/resources/MainMenu.nib/info.nib
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IBDocumentLocation</key>
+	<string>159 127 356 240 0 0 1920 1178 </string>
+	<key>IBEditorPositions</key>
+	<dict>
+		<key>29</key>
+		<string>413 971 130 44 0 0 1920 1178 </string>
+	</dict>
+	<key>IBFramework Version</key>
+	<string>443.0</string>
+	<key>IBOpenObjects</key>
+	<array>
+		<integer>29</integer>
+	</array>
+	<key>IBSystem Version</key>
+	<string>8F46</string>
+</dict>
+</plist>
diff --git a/widget/cocoa/resources/MainMenu.nib/keyedobjects.nib b/widget/cocoa/resources/MainMenu.nib/keyedobjects.nib
new file mode 100644
index 0000000000..16b3f7e523
--- /dev/null
+++ b/widget/cocoa/resources/MainMenu.nib/keyedobjects.nib
diff --git a/widget/moz.build b/widget/moz.build
index e40bf6a61a..6a88fab706 100644
--- a/widget/moz.build
+++ b/widget/moz.build
@@ -5,6 +5,9 @@
 
 toolkit = CONFIG['MOZ_WIDGET_TOOLKIT']
 
+if toolkit in ('cocoa', 'uikit'):
+    DIRS += [toolkit]
+
 if toolkit in ('gtk2', 'gtk3'):
     EXPORTS += ['nsIPrintDialogService.h']
 
@@ -25,8 +28,19 @@ if toolkit == 'windows':
         'nsIWindowsUIUtils.idl',
         'nsIWinTaskbar.idl',
     ]
+elif toolkit == 'cocoa':
+    XPIDL_SOURCES += [
+        'nsIMacDockSupport.idl',
+        'nsIMacWebAppUtils.idl',
+        'nsIStandaloneNativeMenu.idl',
+        'nsISystemStatusBar.idl',
+        'nsITaskbarProgress.idl',
+    ]
+    EXPORTS += [
+        'nsIPrintDialogService.h',
+    ]
 
-if toolkit in ('gtk2', 'gtk3'):
+if toolkit in ('cocoa', 'gtk2', 'gtk3'):
     EXPORTS += ['nsINativeMenuService.h']
 
 # Don't build the DSO under the 'build' directory as windows does.
@@ -202,15 +216,15 @@ if CONFIG['MOZ_X11']:
         'WindowSurfaceX11SHM.cpp',
     ]
 
-if toolkit in ('windows'):
+if toolkit in ('cocoa', 'windows'):
     UNIFIED_SOURCES += [
         'nsBaseClipboard.cpp',
     ]
 
-if toolkit in {'gtk2', 'gtk3', 'windows', 'uikit'}:
+if toolkit in {'gtk2', 'gtk3', 'cocoa', 'windows', 'uikit'}:
     UNIFIED_SOURCES += ['nsBaseFilePicker.cpp']
 
-if toolkit in ('gtk2', 'gtk3', 'windows'):
+if toolkit in ('gtk2', 'gtk3', 'windows', 'cocoa'):
     UNIFIED_SOURCES += ['nsNativeTheme.cpp']
 
 if toolkit == 'gtk3':
diff --git a/widget/nsIMacDockSupport.idl b/widget/nsIMacDockSupport.idl
new file mode 100644
index 0000000000..5783e9c0b9
--- /dev/null
+++ b/widget/nsIMacDockSupport.idl
@@ -0,0 +1,39 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIStandaloneNativeMenu;
+
+/**
+ * Allow applications to interface with the Mac OS X Dock.
+ *
+ * Applications may indicate progress on their Dock icon. Only one such
+ * progress indicator is available to the entire application.
+ */
+
+[scriptable, uuid(8BE66B0C-5F71-4B74-98CF-6C2551B999B1)]
+interface nsIMacDockSupport : nsISupports
+{
+  /**
+   * Menu to use for application-specific dock menu items.
+   */
+  attribute nsIStandaloneNativeMenu dockMenu;
+
+  /**
+   * Activate the application. This should be used by an application to
+   * activate itself when a dock menu is selected as selection of a dock menu
+   * item does not automatically activate the application.
+   *
+   * @param aIgnoreOtherApplications If false, the application is activated
+   *        only if no other application is currently active. If true, the
+   *        application activates regardless. 
+   */
+  void activateApplication(in boolean aIgnoreOtherApplications);
+
+  /**
+   * Text used to badge the dock tile.
+   */
+  attribute AString badgeText;
+};
diff --git a/widget/nsIMacWebAppUtils.idl b/widget/nsIMacWebAppUtils.idl
new file mode 100644
index 0000000000..4d570a8bf0
--- /dev/null
+++ b/widget/nsIMacWebAppUtils.idl
@@ -0,0 +1,35 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIMacWebAppUtils;
+
+[scriptable, function, uuid(8c899c4f-58c1-4b74-9034-3bb64e484b68)]
+interface nsITrashAppCallback : nsISupports
+{
+  void trashAppFinished(in nsresult rv);
+};
+
+/**
+ * Allow MozApps API to locate and manipulate natively installed apps
+ */
+
+[scriptable, uuid(c69cf343-ea41-428b-b161-4655fd54d8e7)]
+interface nsIMacWebAppUtils : nsISupports {
+  /**
+   * Find the path for an app with the given signature.
+   */
+  AString pathForAppWithIdentifier(in AString bundleIdentifier);
+
+  /**
+   * Launch the app with the given identifier, if it exists.
+   */
+  void launchAppWithIdentifier(in AString bundleIdentifier);
+
+  /**
+   * Move the app from the given directory to the Trash.
+   */
+  void trashApp(in AString path, in nsITrashAppCallback callback);
+};
diff --git a/widget/nsISystemStatusBar.idl b/widget/nsISystemStatusBar.idl
new file mode 100644
index 0000000000..9db8015199
--- /dev/null
+++ b/widget/nsISystemStatusBar.idl
@@ -0,0 +1,36 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIDOMElement;
+
+/**
+ * Allow applications to interface with the Mac OS X system status bar.
+ */
+
+[scriptable, uuid(24493180-ee81-4b7c-8b17-9e69480b7b8a)]
+interface nsISystemStatusBar : nsISupports
+{
+  /**
+   * Add an item to the system status bar. Each item can only be present once,
+   * subsequent addItem calls with the same element will be ignored.
+   * The system status bar holds a strong reference to the added XUL menu
+   * element and the item will stay in the status bar until it is removed via
+   * a call to removeItem, or until the process shuts down.
+   * @param aDOMMenuElement A XUL menu element that contains a XUL menupopup
+   *                        with regular menu content. The menu's icon is put
+   *                        into the system status bar; clicking it will open
+   *                        a menu with the contents of the menupopup.
+   *                        The menu label is not shown.
+   */
+  void addItem(in nsIDOMElement aDOMMenuElement);
+
+  /**
+   * Remove a previously-added item from the menu bar. Calling this with an
+   * element that has not been added before will be silently ignored.
+   * @param aDOMMenuElement The XUL menu element that you called addItem with.
+   */
+  void removeItem(in nsIDOMElement aDOMMenuElement);
+};
diff --git a/widget/uikit/GfxInfo.cpp b/widget/uikit/GfxInfo.cpp
new file mode 100644
index 0000000000..cabe993dd0
--- /dev/null
+++ b/widget/uikit/GfxInfo.cpp
@@ -0,0 +1,222 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "GfxInfo.h"
+#include "nsServiceManagerUtils.h"
+
+namespace mozilla {
+namespace widget {
+
+
+#ifdef DEBUG
+NS_IMPL_ISUPPORTS_INHERITED(GfxInfo, GfxInfoBase, nsIGfxInfoDebug)
+#endif
+
+GfxInfo::GfxInfo()
+{
+}
+
+GfxInfo::~GfxInfo()
+{
+}
+
+nsresult
+GfxInfo::GetD2DEnabled(bool *aEnabled)
+{
+  return NS_ERROR_FAILURE;
+}
+
+nsresult
+GfxInfo::GetDWriteEnabled(bool *aEnabled)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetDWriteVersion(nsAString & aDwriteVersion)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetCleartypeParameters(nsAString & aCleartypeParams)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDescription(nsAString & aAdapterDescription)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDescription2(nsAString & aAdapterDescription)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterRAM(nsAString & aAdapterRAM)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterRAM2(nsAString & aAdapterRAM)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriver(nsAString & aAdapterDriver)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriver2(nsAString & aAdapterDriver)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverVersion(nsAString & aAdapterDriverVersion)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverVersion2(nsAString & aAdapterDriverVersion)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverDate(nsAString & aAdapterDriverDate)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDriverDate2(nsAString & aAdapterDriverDate)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterVendorID(nsAString & aAdapterVendorID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterVendorID2(nsAString & aAdapterVendorID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDeviceID(nsAString & aAdapterDeviceID)
+{
+  return NS_ERROR_FAILURE;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterDeviceID2(nsAString & aAdapterDeviceID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterSubsysID(nsAString & aAdapterSubsysID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetAdapterSubsysID2(nsAString & aAdapterSubsysID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+GfxInfo::GetIsGPU2Active(bool* aIsGPU2Active)
+{
+  return NS_ERROR_FAILURE;
+}
+
+const nsTArray<GfxDriverInfo>&
+GfxInfo::GetGfxDriverInfo()
+{
+  if (mDriverInfo->IsEmpty()) {
+    APPEND_TO_DRIVER_BLOCKLIST2(OperatingSystem::Ios,
+      (nsAString&) GfxDriverInfo::GetDeviceVendor(VendorAll), GfxDriverInfo::allDevices,
+      nsIGfxInfo::FEATURE_OPENGL_LAYERS, nsIGfxInfo::FEATURE_STATUS_OK,
+      DRIVER_COMPARISON_IGNORED, GfxDriverInfo::allDriverVersions );
+  }
+
+  return *mDriverInfo;
+}
+
+nsresult
+GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
+                              int32_t *aStatus,
+                              nsAString & aSuggestedDriverVersion,
+                              const nsTArray<GfxDriverInfo>& aDriverInfo,
+                              OperatingSystem* aOS /* = nullptr */)
+{
+  NS_ENSURE_ARG_POINTER(aStatus);
+  aSuggestedDriverVersion.SetIsVoid(true);
+  *aStatus = nsIGfxInfo::FEATURE_STATUS_UNKNOWN;
+  if (aOS)
+    *aOS = OperatingSystem::Ios;
+
+  if (mShutdownOccurred) {
+    return NS_OK;
+  }
+
+  // OpenGL layers are never blacklisted on iOS.
+  // This early return is so we avoid potentially slow
+  // GLStrings initialization on startup when we initialize GL layers.
+  if (aFeature == nsIGfxInfo::FEATURE_OPENGL_LAYERS ||
+      aFeature == nsIGfxInfo::FEATURE_WEBGL_OPENGL ||
+      aFeature == nsIGfxInfo::FEATURE_WEBGL_MSAA) {
+    *aStatus = nsIGfxInfo::FEATURE_STATUS_OK;
+    return NS_OK;
+  }
+
+  return GfxInfoBase::GetFeatureStatusImpl(aFeature, aStatus, aSuggestedDriverVersion, aDriverInfo, aOS);
+}
+
+#ifdef DEBUG
+
+// Implement nsIGfxInfoDebug
+
+NS_IMETHODIMP GfxInfo::SpoofVendorID(const nsAString & aVendorID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP GfxInfo::SpoofDeviceID(const nsAString & aDeviceID)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP GfxInfo::SpoofDriverVersion(const nsAString & aDriverVersion)
+{
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP GfxInfo::SpoofOSVersion(uint32_t aVersion)
+{
+  return NS_ERROR_FAILURE;
+}
+
+#endif
+
+}
+}
diff --git a/widget/uikit/GfxInfo.h b/widget/uikit/GfxInfo.h
new file mode 100644
index 0000000000..16a2242515
--- /dev/null
+++ b/widget/uikit/GfxInfo.h
@@ -0,0 +1,78 @@
+/* vim: se cin sw=2 ts=2 et : */
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef __mozilla_widget_GfxInfo_h__
+#define __mozilla_widget_GfxInfo_h__
+
+#include "GfxInfoBase.h"
+#include "GfxDriverInfo.h"
+
+#include "nsString.h"
+#include "mozilla/UniquePtr.h"
+
+namespace mozilla {
+
+namespace gl {
+class GLContext;
+}
+
+namespace widget {
+
+class GfxInfo : public GfxInfoBase
+{
+private:
+  ~GfxInfo();
+
+public:
+  GfxInfo();
+
+  // We only declare the subset of nsIGfxInfo that we actually implement. The
+  // rest is brought forward from GfxInfoBase.
+  NS_IMETHOD GetD2DEnabled(bool *aD2DEnabled);
+  NS_IMETHOD GetDWriteEnabled(bool *aDWriteEnabled);
+  NS_IMETHOD GetDWriteVersion(nsAString & aDwriteVersion);
+  NS_IMETHOD GetCleartypeParameters(nsAString & aCleartypeParams);
+  NS_IMETHOD GetAdapterDescription(nsAString & aAdapterDescription);
+  NS_IMETHOD GetAdapterDriver(nsAString & aAdapterDriver);
+  NS_IMETHOD GetAdapterVendorID(nsAString & aAdapterVendorID);
+  NS_IMETHOD GetAdapterDeviceID(nsAString & aAdapterDeviceID);
+  NS_IMETHOD GetAdapterSubsysID(nsAString & aAdapterSubsysID);
+  NS_IMETHOD GetAdapterRAM(nsAString & aAdapterRAM);
+  NS_IMETHOD GetAdapterDriverVersion(nsAString & aAdapterDriverVersion);
+  NS_IMETHOD GetAdapterDriverDate(nsAString & aAdapterDriverDate);
+  NS_IMETHOD GetAdapterDescription2(nsAString & aAdapterDescription);
+  NS_IMETHOD GetAdapterDriver2(nsAString & aAdapterDriver);
+  NS_IMETHOD GetAdapterVendorID2(nsAString & aAdapterVendorID);
+  NS_IMETHOD GetAdapterDeviceID2(nsAString & aAdapterDeviceID);
+  NS_IMETHOD GetAdapterSubsysID2(nsAString & aAdapterSubsysID);
+  NS_IMETHOD GetAdapterRAM2(nsAString & aAdapterRAM);
+  NS_IMETHOD GetAdapterDriverVersion2(nsAString & aAdapterDriverVersion);
+  NS_IMETHOD GetAdapterDriverDate2(nsAString & aAdapterDriverDate);
+  NS_IMETHOD GetIsGPU2Active(bool *aIsGPU2Active);
+  using GfxInfoBase::GetFeatureStatus;
+  using GfxInfoBase::GetFeatureSuggestedDriverVersion;
+  using GfxInfoBase::GetWebGLParameter;
+
+#ifdef DEBUG
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_NSIGFXINFODEBUG
+#endif
+
+protected:
+
+  virtual nsresult GetFeatureStatusImpl(int32_t aFeature,
+                                        int32_t *aStatus,
+                                        nsAString & aSuggestedDriverVersion,
+                                        const nsTArray<GfxDriverInfo>& aDriverInfo,
+                                        OperatingSystem* aOS = nullptr);
+  virtual const nsTArray<GfxDriverInfo>& GetGfxDriverInfo();
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif /* __mozilla_widget_GfxInfo_h__ */
diff --git a/widget/uikit/moz.build b/widget/uikit/moz.build
new file mode 100644
index 0000000000..2c6c188de6
--- /dev/null
+++ b/widget/uikit/moz.build
@@ -0,0 +1,18 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+SOURCES += [
+    'GfxInfo.cpp',
+    'nsAppShell.mm',
+    'nsLookAndFeel.mm',
+    'nsScreenManager.mm',
+    'nsWidgetFactory.mm',
+    'nsWindow.mm',
+]
+
+FINAL_LIBRARY = 'xul'
+LOCAL_INCLUDES += [
+    '/widget',
+]
diff --git a/widget/uikit/nsAppShell.h b/widget/uikit/nsAppShell.h
new file mode 100644
index 0000000000..a88fa8b4f1
--- /dev/null
+++ b/widget/uikit/nsAppShell.h
@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Runs the main native UIKit run loop, interrupting it as needed to process
+ * Gecko events.
+ */
+
+#ifndef nsAppShell_h_
+#define nsAppShell_h_
+
+#include "nsBaseAppShell.h"
+#include "nsTArray.h"
+
+#include <Foundation/NSAutoreleasePool.h>
+#include <CoreFoundation/CFRunLoop.h>
+#include <UIKit/UIWindow.h>
+
+@class AppShellDelegate;
+
+class nsAppShell : public nsBaseAppShell
+{
+public:
+  NS_IMETHOD ResumeNative(void);
+
+  nsAppShell();
+
+  nsresult Init();
+
+  NS_IMETHOD Run(void);
+  NS_IMETHOD Exit(void);
+  // Called by the application delegate
+  void WillTerminate(void);
+
+  static nsAppShell* gAppShell;
+  static UIWindow* gWindow;
+  static NSMutableArray* gTopLevelViews;
+
+protected:
+  virtual ~nsAppShell();
+
+  static void ProcessGeckoEvents(void* aInfo);
+  virtual void ScheduleNativeEventCallback();
+  virtual bool ProcessNextNativeEvent(bool aMayWait);
+
+  NSAutoreleasePool* mAutoreleasePool;
+  AppShellDelegate*  mDelegate;
+  CFRunLoopRef       mCFRunLoop;
+  CFRunLoopSourceRef mCFRunLoopSource;
+
+  bool               mTerminated;
+  bool               mNotifiedWillTerminate;
+};
+
+#endif // nsAppShell_h_
diff --git a/widget/uikit/nsAppShell.mm b/widget/uikit/nsAppShell.mm
new file mode 100644
index 0000000000..ac007132fd
--- /dev/null
+++ b/widget/uikit/nsAppShell.mm
@@ -0,0 +1,271 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <UIKit/UIApplication.h>
+#import <UIKit/UIScreen.h>
+#import <UIKit/UIWindow.h>
+#import <UIKit/UIViewController.h>
+
+#include "nsAppShell.h"
+#include "nsCOMPtr.h"
+#include "nsIFile.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsString.h"
+#include "nsIRollupListener.h"
+#include "nsIWidget.h"
+#include "nsThreadUtils.h"
+#include "nsIWindowMediator.h"
+#include "nsMemoryPressure.h"
+#include "nsServiceManagerUtils.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIWebBrowserChrome.h"
+
+nsAppShell *nsAppShell::gAppShell = NULL;
+UIWindow *nsAppShell::gWindow = nil;
+NSMutableArray *nsAppShell::gTopLevelViews = [[NSMutableArray alloc] init];
+
+#define ALOG(args...) fprintf(stderr, args); fprintf(stderr, "\n")
+
+// ViewController
+@interface ViewController : UIViewController
+@end
+
+
+@implementation ViewController
+
+- (void)loadView {
+    ALOG("[ViewController loadView]");
+    CGRect r = {{0, 0}, {100, 100}};
+    self.view = [[UIView alloc] initWithFrame:r];
+    [self.view setBackgroundColor:[UIColor lightGrayColor]];
+    // add all of the top level views as children
+    for (UIView* v in nsAppShell::gTopLevelViews) {
+        ALOG("[ViewController.view addSubView:%p]", v);
+        [self.view addSubview:v];
+    }
+    [nsAppShell::gTopLevelViews release];
+    nsAppShell::gTopLevelViews = nil;
+}
+@end
+
+// AppShellDelegate
+//
+// Acts as a delegate for the UIApplication
+
+@interface AppShellDelegate : NSObject <UIApplicationDelegate> {
+}
+@property (strong, nonatomic) UIWindow *window;
+@end
+
+@implementation AppShellDelegate
+
+- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
+{
+  ALOG("[AppShellDelegate application:didFinishLaunchingWithOptions:]");
+  // We only create one window, since we can only display one window at
+  // a time anyway. Also, iOS 4 fails to display UIWindows if you
+  // create them before calling UIApplicationMain, so this makes more sense.
+  nsAppShell::gWindow = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]] retain];
+  self.window = nsAppShell::gWindow;
+
+  self.window.rootViewController = [[ViewController alloc] init];
+
+  // just to make things more visible for now
+  nsAppShell::gWindow.backgroundColor = [UIColor blueColor];
+  [nsAppShell::gWindow makeKeyAndVisible];
+
+  return YES;
+}
+
+- (void)applicationWillTerminate:(UIApplication *)application
+{
+  ALOG("[AppShellDelegate applicationWillTerminate:]");
+  nsAppShell::gAppShell->WillTerminate();
+}
+
+- (void)applicationDidBecomeActive:(UIApplication *)application
+{
+  ALOG("[AppShellDelegate applicationDidBecomeActive:]");
+}
+
+- (void)applicationWillResignActive:(UIApplication *)application
+{
+  ALOG("[AppShellDelegate applicationWillResignActive:]");
+}
+
+- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application
+{
+  ALOG("[AppShellDelegate applicationDidReceiveMemoryWarning:]");
+  NS_DispatchMemoryPressure(MemPressure_New);
+}
+@end
+
+// nsAppShell implementation
+
+NS_IMETHODIMP
+nsAppShell::ResumeNative(void)
+{
+  return nsBaseAppShell::ResumeNative();
+}
+
+nsAppShell::nsAppShell()
+  : mAutoreleasePool(NULL),
+    mDelegate(NULL),
+    mCFRunLoop(NULL),
+    mCFRunLoopSource(NULL),
+    mTerminated(false),
+    mNotifiedWillTerminate(false)
+{
+  gAppShell = this;
+}
+
+nsAppShell::~nsAppShell()
+{
+  if (mAutoreleasePool) {
+    [mAutoreleasePool release];
+    mAutoreleasePool = NULL;
+  }
+
+  if (mCFRunLoop) {
+    if (mCFRunLoopSource) {
+      ::CFRunLoopRemoveSource(mCFRunLoop, mCFRunLoopSource,
+                              kCFRunLoopCommonModes);
+      ::CFRelease(mCFRunLoopSource);
+    }
+    ::CFRelease(mCFRunLoop);
+  }
+
+  gAppShell = NULL;
+}
+
+// Init
+//
+// public
+nsresult
+nsAppShell::Init()
+{
+  mAutoreleasePool = [[NSAutoreleasePool alloc] init];
+
+  // Add a CFRunLoopSource to the main native run loop.  The source is
+  // responsible for interrupting the run loop when Gecko events are ready.
+
+  mCFRunLoop = [[NSRunLoop currentRunLoop] getCFRunLoop];
+  NS_ENSURE_STATE(mCFRunLoop);
+  ::CFRetain(mCFRunLoop);
+
+  CFRunLoopSourceContext context;
+  bzero(&context, sizeof(context));
+  // context.version = 0;
+  context.info = this;
+  context.perform = ProcessGeckoEvents;
+
+  mCFRunLoopSource = ::CFRunLoopSourceCreate(kCFAllocatorDefault, 0, &context);
+  NS_ENSURE_STATE(mCFRunLoopSource);
+
+  ::CFRunLoopAddSource(mCFRunLoop, mCFRunLoopSource, kCFRunLoopCommonModes);
+
+  return nsBaseAppShell::Init();
+}
+
+// ProcessGeckoEvents
+//
+// The "perform" target of mCFRunLoop, called when mCFRunLoopSource is
+// signalled from ScheduleNativeEventCallback.
+//
+// protected static
+void
+nsAppShell::ProcessGeckoEvents(void* aInfo)
+{
+  nsAppShell* self = static_cast<nsAppShell*> (aInfo);
+  self->NativeEventCallback();
+  self->Release();
+}
+
+// WillTerminate
+//
+// public
+void
+nsAppShell::WillTerminate()
+{
+  mNotifiedWillTerminate = true;
+  if (mTerminated)
+    return;
+  mTerminated = true;
+  // We won't get another chance to process events
+  NS_ProcessPendingEvents(NS_GetCurrentThread());
+
+  // Unless we call nsBaseAppShell::Exit() here, it might not get called
+  // at all.
+  nsBaseAppShell::Exit();
+}
+
+// ScheduleNativeEventCallback
+//
+// protected virtual
+void
+nsAppShell::ScheduleNativeEventCallback()
+{
+  if (mTerminated)
+    return;
+
+  NS_ADDREF_THIS();
+
+  // This will invoke ProcessGeckoEvents on the main thread.
+  ::CFRunLoopSourceSignal(mCFRunLoopSource);
+  ::CFRunLoopWakeUp(mCFRunLoop);
+}
+
+// ProcessNextNativeEvent
+//
+// protected virtual
+bool
+nsAppShell::ProcessNextNativeEvent(bool aMayWait)
+{
+  if (mTerminated)
+    return false;
+
+  NSString* currentMode = nil;
+  NSDate* waitUntil = nil;
+  if (aMayWait)
+    waitUntil = [NSDate distantFuture];
+  NSRunLoop* currentRunLoop = [NSRunLoop currentRunLoop];
+
+  BOOL eventProcessed = NO;
+  do {
+    currentMode = [currentRunLoop currentMode];
+    if (!currentMode)
+      currentMode = NSDefaultRunLoopMode;
+
+    if (aMayWait)
+      eventProcessed = [currentRunLoop runMode:currentMode beforeDate:waitUntil];
+    else
+      [currentRunLoop acceptInputForMode:currentMode beforeDate:waitUntil];
+  } while(eventProcessed && aMayWait);
+
+  return false;
+}
+
+// Run
+//
+// public
+NS_IMETHODIMP
+nsAppShell::Run(void)
+{
+  ALOG("nsAppShell::Run");
+  char argv[1][4] = {"app"};
+  UIApplicationMain(1, (char**)argv, nil, @"AppShellDelegate");
+  // UIApplicationMain doesn't exit. :-(
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppShell::Exit(void)
+{
+  if (mTerminated)
+    return NS_OK;
+
+  mTerminated = true;
+  return nsBaseAppShell::Exit();
+}
diff --git a/widget/uikit/nsLookAndFeel.h b/widget/uikit/nsLookAndFeel.h
new file mode 100644
index 0000000000..91c0c2d73e
--- /dev/null
+++ b/widget/uikit/nsLookAndFeel.h
@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef __nsLookAndFeel
+#define __nsLookAndFeel
+
+#include "nsXPLookAndFeel.h"
+
+class nsLookAndFeel: public nsXPLookAndFeel
+{
+public:
+    nsLookAndFeel();
+    virtual ~nsLookAndFeel();
+
+    virtual nsresult NativeGetColor(const ColorID aID, nscolor &aResult);
+    virtual nsresult GetIntImpl(IntID aID, int32_t &aResult);
+    virtual nsresult GetFloatImpl(FloatID aID, float &aResult);
+    virtual bool GetFontImpl(FontID aID, nsString& aFontName,
+                             gfxFontStyle& aFontStyle,
+                             float aDevPixPerCSSPixel);
+    virtual char16_t GetPasswordCharacterImpl()
+    {
+        // unicode value for the bullet character, used for password textfields.
+        return 0x2022;
+    }
+
+    static bool UseOverlayScrollbars()
+    {
+        return true;
+    }
+};
+
+#endif
diff --git a/widget/uikit/nsLookAndFeel.mm b/widget/uikit/nsLookAndFeel.mm
new file mode 100644
index 0000000000..bb593eb51e
--- /dev/null
+++ b/widget/uikit/nsLookAndFeel.mm
@@ -0,0 +1,401 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <UIKit/UIColor.h>
+#import <UIKit/UIInterface.h>
+
+#include "nsLookAndFeel.h"
+#include "nsStyleConsts.h"
+#include "gfxFont.h"
+#include "gfxFontConstants.h"
+
+nsLookAndFeel::nsLookAndFeel()
+    : nsXPLookAndFeel()
+{
+}
+
+nsLookAndFeel::~nsLookAndFeel()
+{
+}
+
+static nscolor GetColorFromUIColor(UIColor* aColor)
+{
+    CGColorRef cgColor = [aColor CGColor];
+    CGColorSpaceModel model = CGColorSpaceGetModel(CGColorGetColorSpace(cgColor));
+    const CGFloat* components = CGColorGetComponents(cgColor);
+    if (model == kCGColorSpaceModelRGB) {
+        return NS_RGB((unsigned int)(components[0] * 255.0),
+                      (unsigned int)(components[1] * 255.0),
+                      (unsigned int)(components[2] * 255.0));
+    }
+    else if (model == kCGColorSpaceModelMonochrome) {
+        unsigned int val = (unsigned int)(components[0] * 255.0);
+        return NS_RGBA(val, val, val,
+                       (unsigned int)(components[1] * 255.0));
+    }
+    NS_NOTREACHED("Unhandled color space!");
+    return 0;
+}
+
+nsresult
+nsLookAndFeel::NativeGetColor(const ColorID aID, nscolor &aResult)
+{
+  nsresult res = NS_OK;
+
+  switch (aID) {
+    case eColorID_WindowBackground:
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_WindowForeground:
+      aResult = NS_RGB(0x00,0x00,0x00);
+      break;
+    case eColorID_WidgetBackground:
+      aResult = NS_RGB(0xdd,0xdd,0xdd);
+      break;
+    case eColorID_WidgetForeground:
+      aResult = NS_RGB(0x00,0x00,0x00);
+      break;
+    case eColorID_WidgetSelectBackground:
+      aResult = NS_RGB(0x80,0x80,0x80);
+      break;
+    case eColorID_WidgetSelectForeground:
+      aResult = NS_RGB(0x00,0x00,0x80);
+      break;
+    case eColorID_Widget3DHighlight:
+      aResult = NS_RGB(0xa0,0xa0,0xa0);
+      break;
+    case eColorID_Widget3DShadow:
+      aResult = NS_RGB(0x40,0x40,0x40);
+      break;
+    case eColorID_TextBackground:
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_TextForeground:
+      aResult = NS_RGB(0x00,0x00,0x00);
+      break;
+    case eColorID_TextSelectBackground:
+    case eColorID_highlight: // CSS2 color
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID__moz_menuhover:
+      aResult = NS_RGB(0xee,0xee,0xee);
+      break;
+    case eColorID_TextSelectForeground:
+    case eColorID_highlighttext:  // CSS2 color
+    case eColorID__moz_menuhovertext:
+      GetColor(eColorID_TextSelectBackground, aResult);
+      if (aResult == 0x000000)
+        aResult = NS_RGB(0xff,0xff,0xff);
+      else
+        aResult = NS_DONT_CHANGE_COLOR;
+      break;
+    case eColorID_IMESelectedRawTextBackground:
+    case eColorID_IMESelectedConvertedTextBackground:
+    case eColorID_IMERawInputBackground:
+    case eColorID_IMEConvertedTextBackground:
+      aResult = NS_TRANSPARENT;
+      break;
+    case eColorID_IMESelectedRawTextForeground:
+    case eColorID_IMESelectedConvertedTextForeground:
+    case eColorID_IMERawInputForeground:
+    case eColorID_IMEConvertedTextForeground:
+      aResult = NS_SAME_AS_FOREGROUND_COLOR;
+      break;
+    case eColorID_IMERawInputUnderline:
+    case eColorID_IMEConvertedTextUnderline:
+      aResult = NS_40PERCENT_FOREGROUND_COLOR;
+      break;
+    case eColorID_IMESelectedRawTextUnderline:
+    case eColorID_IMESelectedConvertedTextUnderline:
+      aResult = NS_SAME_AS_FOREGROUND_COLOR;
+      break;
+    case eColorID_SpellCheckerUnderline:
+      aResult = NS_RGB(0xff, 0, 0);
+      break;
+
+    //
+    // css2 system colors http://www.w3.org/TR/REC-CSS2/ui.html#system-colors
+    //
+    case eColorID_buttontext:
+    case eColorID__moz_buttonhovertext:
+    case eColorID_captiontext:
+    case eColorID_menutext:
+    case eColorID_infotext:
+    case eColorID__moz_menubartext:
+    case eColorID_windowtext:
+      aResult = GetColorFromUIColor([UIColor darkTextColor]);
+      break;
+    case eColorID_activecaption:
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_activeborder:
+      aResult = NS_RGB(0x00,0x00,0x00);
+      break;
+     case eColorID_appworkspace:
+      aResult = NS_RGB(0xFF,0xFF,0xFF);
+      break;
+    case eColorID_background:
+      aResult = NS_RGB(0x63,0x63,0xCE);
+      break;
+    case eColorID_buttonface:
+    case eColorID__moz_buttonhoverface:
+      aResult = NS_RGB(0xF0,0xF0,0xF0);
+      break;
+    case eColorID_buttonhighlight:
+      aResult = NS_RGB(0xFF,0xFF,0xFF);
+      break;
+    case eColorID_buttonshadow:
+      aResult = NS_RGB(0xDC,0xDC,0xDC);
+      break;
+    case eColorID_graytext:
+      aResult = NS_RGB(0x44,0x44,0x44);
+      break;
+    case eColorID_inactiveborder:
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_inactivecaption:
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID_inactivecaptiontext:
+      aResult = NS_RGB(0x45,0x45,0x45);
+      break;
+    case eColorID_scrollbar:
+      aResult = NS_RGB(0,0,0); //XXX
+      break;
+    case eColorID_threeddarkshadow:
+      aResult = NS_RGB(0xDC,0xDC,0xDC);
+      break;
+    case eColorID_threedshadow:
+      aResult = NS_RGB(0xE0,0xE0,0xE0);
+      break;
+    case eColorID_threedface:
+      aResult = NS_RGB(0xF0,0xF0,0xF0);
+      break;
+    case eColorID_threedhighlight:
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_threedlightshadow:
+      aResult = NS_RGB(0xDA,0xDA,0xDA);
+      break;
+    case eColorID_menu:
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID_infobackground:
+      aResult = NS_RGB(0xFF,0xFF,0xC7);
+      break;
+    case eColorID_windowframe:
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID_window:
+    case eColorID__moz_field:
+    case eColorID__moz_combobox:
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID__moz_fieldtext:
+    case eColorID__moz_comboboxtext:
+      aResult = GetColorFromUIColor([UIColor darkTextColor]);
+      break;
+    case eColorID__moz_dialog:
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID__moz_dialogtext:
+    case eColorID__moz_cellhighlighttext:
+    case eColorID__moz_html_cellhighlighttext:
+      aResult = GetColorFromUIColor([UIColor darkTextColor]);
+      break;
+    case eColorID__moz_dragtargetzone:
+    case eColorID__moz_mac_chrome_active:
+    case eColorID__moz_mac_chrome_inactive:
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID__moz_mac_focusring:
+      aResult = NS_RGB(0x3F,0x98,0xDD);
+      break;
+    case eColorID__moz_mac_menushadow:
+      aResult = NS_RGB(0xA3,0xA3,0xA3);
+      break;
+    case eColorID__moz_mac_menutextdisable:
+      aResult = NS_RGB(0x88,0x88,0x88);
+      break;
+    case eColorID__moz_mac_menutextselect:
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID__moz_mac_disabledtoolbartext:
+      aResult = NS_RGB(0x3F,0x3F,0x3F);
+      break;
+    case eColorID__moz_mac_menuselect:
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID__moz_buttondefault:
+      aResult = NS_RGB(0xDC,0xDC,0xDC);
+      break;
+    case eColorID__moz_cellhighlight:
+    case eColorID__moz_html_cellhighlight:
+    case eColorID__moz_mac_secondaryhighlight:
+      // For inactive list selection
+      aResult = NS_RGB(0xaa,0xaa,0xaa);
+      break;
+    case eColorID__moz_eventreerow:
+      // Background color of even list rows.
+      aResult = NS_RGB(0xff,0xff,0xff);
+      break;
+    case eColorID__moz_oddtreerow:
+      // Background color of odd list rows.
+      aResult = NS_TRANSPARENT;
+      break;
+    case eColorID__moz_nativehyperlinktext:
+      // There appears to be no available system defined color. HARDCODING to the appropriate color.
+      aResult = NS_RGB(0x14,0x4F,0xAE);
+      break;
+    default:
+      NS_WARNING("Someone asked nsILookAndFeel for a color I don't know about");
+      aResult = NS_RGB(0xff,0xff,0xff);
+      res = NS_ERROR_FAILURE;
+      break;
+    }
+
+  return res;
+}
+
+NS_IMETHODIMP
+nsLookAndFeel::GetIntImpl(IntID aID, int32_t &aResult)
+{
+  nsresult res = nsXPLookAndFeel::GetIntImpl(aID, aResult);
+  if (NS_SUCCEEDED(res))
+    return res;
+  res = NS_OK;
+
+  switch (aID) {
+    case eIntID_CaretBlinkTime:
+      aResult = 567;
+      break;
+    case eIntID_CaretWidth:
+      aResult = 1;
+      break;
+    case eIntID_ShowCaretDuringSelection:
+      aResult = 0;
+      break;
+    case eIntID_SelectTextfieldsOnKeyFocus:
+      // Select textfield content when focused by kbd
+      // used by nsEventStateManager::sTextfieldSelectModel
+      aResult = 1;
+      break;
+    case eIntID_SubmenuDelay:
+      aResult = 200;
+      break;
+    case eIntID_MenusCanOverlapOSBar:
+      // xul popups are not allowed to overlap the menubar.
+      aResult = 0;
+      break;
+    case eIntID_SkipNavigatingDisabledMenuItem:
+      aResult = 1;
+      break;
+    case eIntID_DragThresholdX:
+    case eIntID_DragThresholdY:
+      aResult = 4;
+      break;
+    case eIntID_ScrollArrowStyle:
+      aResult = eScrollArrow_None;
+      break;
+    case eIntID_ScrollSliderStyle:
+      aResult = eScrollThumbStyle_Proportional;
+      break;
+    case eIntID_TreeOpenDelay:
+      aResult = 1000;
+      break;
+    case eIntID_TreeCloseDelay:
+      aResult = 1000;
+      break;
+    case eIntID_TreeLazyScrollDelay:
+      aResult = 150;
+      break;
+    case eIntID_TreeScrollDelay:
+      aResult = 100;
+      break;
+    case eIntID_TreeScrollLinesMax:
+      aResult = 3;
+      break;
+    case eIntID_DWMCompositor:
+    case eIntID_WindowsClassic:
+    case eIntID_WindowsDefaultTheme:
+    case eIntID_TouchEnabled:
+      aResult = 0;
+      res = NS_ERROR_NOT_IMPLEMENTED;
+      break;
+    case eIntID_MacGraphiteTheme:
+      aResult = 0;
+      break;
+    case eIntID_TabFocusModel:
+      aResult = 1;    // default to just textboxes
+      break;
+    case eIntID_ScrollToClick:
+      aResult = 0;
+      break;
+    case eIntID_ChosenMenuItemsShouldBlink:
+      aResult = 1;
+      break;
+    case eIntID_IMERawInputUnderlineStyle:
+    case eIntID_IMEConvertedTextUnderlineStyle:
+    case eIntID_IMESelectedRawTextUnderlineStyle:
+    case eIntID_IMESelectedConvertedTextUnderline:
+      aResult = NS_STYLE_TEXT_DECORATION_STYLE_SOLID;
+      break;
+    case eIntID_SpellCheckerUnderlineStyle:
+      aResult = NS_STYLE_TEXT_DECORATION_STYLE_DOTTED;
+      break;
+    case eIntID_ContextMenuOffsetVertical:
+    case eIntID_ContextMenuOffsetHorizontal:
+      aResult = 2;
+      break;
+    default:
+      aResult = 0;
+      res = NS_ERROR_FAILURE;
+  }
+  return res;
+}
+
+NS_IMETHODIMP
+nsLookAndFeel::GetFloatImpl(FloatID aID, float &aResult)
+{
+  nsresult res = nsXPLookAndFeel::GetFloatImpl(aID, aResult);
+  if (NS_SUCCEEDED(res))
+    return res;
+  res = NS_OK;
+
+  switch (aID) {
+    case eFloatID_IMEUnderlineRelativeSize:
+      aResult = 2.0f;
+      break;
+    case eFloatID_SpellCheckerUnderlineRelativeSize:
+      aResult = 2.0f;
+      break;
+    default:
+      aResult = -1.0;
+      res = NS_ERROR_FAILURE;
+  }
+
+  return res;
+}
+
+bool
+nsLookAndFeel::GetFontImpl(FontID aID, nsString &aFontName,
+                           gfxFontStyle &aFontStyle,
+                           float aDevPixPerCSSPixel)
+{
+    // hack for now
+    if (aID == eFont_Window || aID == eFont_Document) {
+        aFontStyle.style      = NS_FONT_STYLE_NORMAL;
+        aFontStyle.weight     = NS_FONT_WEIGHT_NORMAL;
+        aFontStyle.stretch    = NS_FONT_STRETCH_NORMAL;
+        aFontStyle.size       = 14 * aDevPixPerCSSPixel;
+        aFontStyle.systemFont = true;
+
+        aFontName.AssignLiteral("sans-serif");
+        return true;
+    }
+
+    //TODO: implement more here?
+    return false;
+}
diff --git a/widget/uikit/nsScreenManager.h b/widget/uikit/nsScreenManager.h
new file mode 100644
index 0000000000..1ff6a87ec7
--- /dev/null
+++ b/widget/uikit/nsScreenManager.h
@@ -0,0 +1,60 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsScreenManager_h_
+#define nsScreenManager_h_
+
+#include "nsBaseScreen.h"
+#include "nsIScreenManager.h"
+#include "nsCOMPtr.h"
+#include "nsRect.h"
+
+@class UIScreen;
+
+class UIKitScreen : public nsBaseScreen
+{
+public:
+    explicit UIKitScreen (UIScreen* screen);
+    ~UIKitScreen () {}
+
+    NS_IMETHOD GetId(uint32_t* outId) {
+        *outId = 0;
+        return NS_OK;
+    }
+
+    NS_IMETHOD GetRect(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetAvailRect(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetRectDisplayPix(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetAvailRectDisplayPix(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+    NS_IMETHOD GetPixelDepth(int32_t* aPixelDepth);
+    NS_IMETHOD GetColorDepth(int32_t* aColorDepth);
+    NS_IMETHOD GetContentsScaleFactor(double* aContentsScaleFactor);
+    NS_IMETHOD GetDefaultCSSScaleFactor(double* aScaleFactor)
+    {
+      return GetContentsScaleFactor(aScaleFactor);
+    }
+
+private:
+    UIScreen* mScreen;
+};
+
+class UIKitScreenManager : public nsIScreenManager
+{
+public:
+    UIKitScreenManager ();
+
+    NS_DECL_ISUPPORTS
+
+    NS_DECL_NSISCREENMANAGER
+
+    static LayoutDeviceIntRect GetBounds();
+
+private:
+    virtual ~UIKitScreenManager () {}
+    //TODO: support >1 screen, iPad supports external displays
+    nsCOMPtr<nsIScreen> mScreen;
+};
+
+#endif // nsScreenManager_h_
diff --git a/widget/uikit/nsScreenManager.mm b/widget/uikit/nsScreenManager.mm
new file mode 100644
index 0000000000..601c911cd9
--- /dev/null
+++ b/widget/uikit/nsScreenManager.mm
@@ -0,0 +1,146 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <UIKit/UIScreen.h>
+
+#include "gfxPoint.h"
+#include "nsScreenManager.h"
+#include "nsAppShell.h"
+
+static LayoutDeviceIntRect gScreenBounds;
+static bool gScreenBoundsSet = false;
+
+UIKitScreen::UIKitScreen(UIScreen* aScreen)
+{
+    mScreen = [aScreen retain];
+}
+
+NS_IMETHODIMP
+UIKitScreen::GetRect(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+    return GetRectDisplayPix(outX, outY, outWidth, outHeight);
+}
+
+NS_IMETHODIMP
+UIKitScreen::GetAvailRect(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+    return GetAvailRectDisplayPix(outX, outY, outWidth, outHeight);
+}
+
+NS_IMETHODIMP
+UIKitScreen::GetRectDisplayPix(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+    nsIntRect rect = UIKitScreenManager::GetBounds();
+    *outX = rect.x;
+    *outY = rect.y;
+    *outWidth = rect.width;
+    *outHeight = rect.height;
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+UIKitScreen::GetAvailRectDisplayPix(int32_t *outX, int32_t *outY, int32_t *outWidth, int32_t *outHeight)
+{
+    CGRect rect = [mScreen applicationFrame];
+    CGFloat scale = [mScreen scale];
+
+    *outX = rect.origin.x * scale;
+    *outY = rect.origin.y * scale;
+    *outWidth = rect.size.width * scale;
+    *outHeight = rect.size.height * scale;
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+UIKitScreen::GetPixelDepth(int32_t *aPixelDepth)
+{
+  // Close enough.
+  *aPixelDepth = 24;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UIKitScreen::GetColorDepth(int32_t *aColorDepth)
+{
+  return GetPixelDepth(aColorDepth);
+}
+
+NS_IMETHODIMP
+UIKitScreen::GetContentsScaleFactor(double* aContentsScaleFactor)
+{
+    *aContentsScaleFactor = [mScreen scale];
+    return NS_OK;
+}
+
+NS_IMPL_ISUPPORTS(UIKitScreenManager, nsIScreenManager)
+
+UIKitScreenManager::UIKitScreenManager()
+: mScreen(new UIKitScreen([UIScreen mainScreen]))
+{
+}
+
+LayoutDeviceIntRect
+UIKitScreenManager::GetBounds()
+{
+    if (!gScreenBoundsSet) {
+        CGRect rect = [[UIScreen mainScreen] bounds];
+        CGFloat scale = [[UIScreen mainScreen] scale];
+        gScreenBounds.x = rect.origin.x * scale;
+        gScreenBounds.y = rect.origin.y * scale;
+        gScreenBounds.width = rect.size.width * scale;
+        gScreenBounds.height = rect.size.height * scale;
+        gScreenBoundsSet = true;
+    }
+    printf("UIKitScreenManager::GetBounds: %d %d %d %d\n",
+           gScreenBounds.x, gScreenBounds.y, gScreenBounds.width, gScreenBounds.height);
+    return gScreenBounds;
+}
+
+NS_IMETHODIMP
+UIKitScreenManager::GetPrimaryScreen(nsIScreen** outScreen)
+{
+  NS_IF_ADDREF(*outScreen = mScreen.get());
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UIKitScreenManager::ScreenForRect(int32_t inLeft,
+                               int32_t inTop,
+                               int32_t inWidth,
+                               int32_t inHeight,
+                               nsIScreen** outScreen)
+{
+  return GetPrimaryScreen(outScreen);
+}
+
+NS_IMETHODIMP
+UIKitScreenManager::ScreenForId(uint32_t id,
+                                nsIScreen** outScreen)
+{
+    return GetPrimaryScreen(outScreen);
+}
+
+NS_IMETHODIMP
+UIKitScreenManager::ScreenForNativeWidget(void* aWidget, nsIScreen** outScreen)
+{
+  return GetPrimaryScreen(outScreen);
+}
+
+NS_IMETHODIMP
+UIKitScreenManager::GetNumberOfScreens(uint32_t* aNumberOfScreens)
+{
+  //TODO: support multiple screens
+  *aNumberOfScreens = 1;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+UIKitScreenManager::GetSystemDefaultScale(float* aScale)
+{
+    *aScale = [UIScreen mainScreen].scale;
+    return NS_OK;
+}
diff --git a/widget/uikit/nsWidgetFactory.mm b/widget/uikit/nsWidgetFactory.mm
new file mode 100644
index 0000000000..9e4f028ff6
--- /dev/null
+++ b/widget/uikit/nsWidgetFactory.mm
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIFactory.h"
+#include "nsISupports.h"
+#include "nsIComponentManager.h"
+#include "mozilla/ModuleUtils.h"
+
+#include "nsWidgetsCID.h"
+
+#include "nsAppShell.h"
+#include "nsAppShellSingleton.h"
+#include "nsLookAndFeel.h"
+#include "nsScreenManager.h"
+#include "nsWindow.h"
+
+NS_GENERIC_FACTORY_CONSTRUCTOR(UIKitScreenManager)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsWindow)
+
+#include "GfxInfo.h"
+namespace mozilla {
+namespace widget {
+// This constructor should really be shared with all platforms.
+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(GfxInfo, Init)
+}
+}
+
+NS_DEFINE_NAMED_CID(NS_WINDOW_CID);
+NS_DEFINE_NAMED_CID(NS_CHILD_CID);
+NS_DEFINE_NAMED_CID(NS_APPSHELL_CID);
+NS_DEFINE_NAMED_CID(NS_SCREENMANAGER_CID);
+NS_DEFINE_NAMED_CID(NS_GFXINFO_CID);
+
+static const mozilla::Module::CIDEntry kWidgetCIDs[] = {
+  { &kNS_WINDOW_CID, false, nullptr, nsWindowConstructor },
+  { &kNS_CHILD_CID, false, nullptr, nsWindowConstructor },
+  { &kNS_APPSHELL_CID, false, nullptr, nsAppShellConstructor },
+  { &kNS_SCREENMANAGER_CID, false, nullptr, UIKitScreenManagerConstructor },
+  { &kNS_GFXINFO_CID, false, nullptr, mozilla::widget::GfxInfoConstructor },
+  { nullptr }
+};
+
+static const mozilla::Module::ContractIDEntry kWidgetContracts[] = {
+  { "@mozilla.org/widgets/window/uikit;1", &kNS_WINDOW_CID },
+  { "@mozilla.org/widgets/childwindow/uikit;1", &kNS_CHILD_CID },
+  { "@mozilla.org/widget/appshell/uikit;1", &kNS_APPSHELL_CID },
+  { "@mozilla.org/gfx/screenmanager;1", &kNS_SCREENMANAGER_CID },
+  { "@mozilla.org/gfx/info;1", &kNS_GFXINFO_CID },
+  { nullptr }
+};
+
+static void
+nsWidgetUIKitModuleDtor()
+{
+  nsLookAndFeel::Shutdown();
+  nsAppShellShutdown();
+}
+
+static const mozilla::Module kWidgetModule = {
+  mozilla::Module::kVersion,
+  kWidgetCIDs,
+  kWidgetContracts,
+  nullptr,
+  nullptr,
+  nsAppShellInit,
+  nsWidgetUIKitModuleDtor
+};
+
+NSMODULE_DEFN(nsWidgetUIKitModule) = &kWidgetModule;
diff --git a/widget/uikit/nsWindow.h b/widget/uikit/nsWindow.h
new file mode 100644
index 0000000000..cb18c09069
--- /dev/null
+++ b/widget/uikit/nsWindow.h
@@ -0,0 +1,125 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef NSWINDOW_H_
+#define NSWINDOW_H_
+
+#include "nsBaseWidget.h"
+#include "gfxPoint.h"
+
+#include "nsTArray.h"
+
+@class UIWindow;
+@class UIView;
+@class ChildView;
+
+class nsWindow :
+    public nsBaseWidget
+{
+    typedef nsBaseWidget Inherited;
+
+public:
+    nsWindow();
+
+    NS_DECL_ISUPPORTS_INHERITED
+
+    //
+    // nsIWidget
+    //
+
+    virtual MOZ_MUST_USE nsresult Create(nsIWidget* aParent,
+                                         nsNativeWidget aNativeParent,
+                                         const LayoutDeviceIntRect& aRect,
+                                         nsWidgetInitData* aInitData = nullptr)
+                                         override;
+    virtual void Destroy() override;
+    NS_IMETHOD Show(bool aState) override;
+    NS_IMETHOD              Enable(bool aState) override {
+        return NS_OK;
+    }
+    virtual bool            IsEnabled() const override {
+        return true;
+    }
+    virtual bool            IsVisible() const override {
+        return mVisible;
+    }
+    NS_IMETHOD              SetFocus(bool aState=false) override;
+    virtual LayoutDeviceIntPoint WidgetToScreenOffset() override;
+
+    virtual void SetBackgroundColor(const nscolor &aColor) override;
+    virtual void* GetNativeData(uint32_t aDataType) override;
+
+    NS_IMETHOD              Move(double aX, double aY) override;
+    virtual void            SetSizeMode(nsSizeMode aMode) override;
+    void                    EnteredFullScreen(bool aFullScreen);
+    NS_IMETHOD              Resize(double aWidth, double aHeight, bool aRepaint) override;
+    NS_IMETHOD              Resize(double aX, double aY, double aWidth, double aHeight, bool aRepaint) override;
+    virtual LayoutDeviceIntRect GetScreenBounds() override;
+    void                    ReportMoveEvent();
+    void                    ReportSizeEvent();
+    void                    ReportSizeModeEvent(nsSizeMode aMode);
+
+    CGFloat                 BackingScaleFactor();
+    void                    BackingScaleFactorChanged();
+    virtual float           GetDPI() override {
+        //XXX: terrible
+        return 326.0f;
+    }
+    virtual double          GetDefaultScaleInternal() override {
+        return BackingScaleFactor();
+    }
+    virtual int32_t         RoundsWidgetCoordinatesTo() override;
+
+    NS_IMETHOD              SetTitle(const nsAString& aTitle) override {
+        return NS_OK;
+    }
+
+    NS_IMETHOD Invalidate(const LayoutDeviceIntRect& aRect) override;
+    virtual nsresult ConfigureChildren(const nsTArray<Configuration>& aConfigurations) override;
+    NS_IMETHOD DispatchEvent(mozilla::WidgetGUIEvent* aEvent,
+                             nsEventStatus& aStatus) override;
+
+    void WillPaintWindow();
+    bool PaintWindow(LayoutDeviceIntRegion aRegion);
+
+    bool HasModalDescendents() { return false; }
+
+    //NS_IMETHOD NotifyIME(const IMENotification& aIMENotification) override;
+    NS_IMETHOD_(void) SetInputContext(
+                        const InputContext& aContext,
+                        const InputContextAction& aAction);
+    NS_IMETHOD_(InputContext) GetInputContext();
+    /*
+    NS_IMETHOD_(bool) ExecuteNativeKeyBinding(
+                        NativeKeyBindingsType aType,
+                        const mozilla::WidgetKeyboardEvent& aEvent,
+                        DoCommandCallback aCallback,
+                        void* aCallbackData) override;
+    */
+
+protected:
+    virtual ~nsWindow();
+    void BringToFront();
+    nsWindow *FindTopLevel();
+    bool IsTopLevel();
+    nsresult GetCurrentOffset(uint32_t &aOffset, uint32_t &aLength);
+    nsresult DeleteRange(int aOffset, int aLen);
+
+    void TearDownView();
+
+    ChildView*   mNativeView;
+    bool mVisible;
+    nsTArray<nsWindow*> mChildren;
+    nsWindow* mParent;
+    InputContext         mInputContext;
+
+    void OnSizeChanged(const mozilla::gfx::IntSize& aSize);
+
+    static void DumpWindows();
+    static void DumpWindows(const nsTArray<nsWindow*>& wins, int indent = 0);
+    static void LogWindow(nsWindow *win, int index, int indent);
+};
+
+#endif /* NSWINDOW_H_ */
diff --git a/widget/uikit/nsWindow.mm b/widget/uikit/nsWindow.mm
new file mode 100644
index 0000000000..874626237c
--- /dev/null
+++ b/widget/uikit/nsWindow.mm
@@ -0,0 +1,862 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import <UIKit/UIEvent.h>
+#import <UIKit/UIGraphics.h>
+#import <UIKit/UIInterface.h>
+#import <UIKit/UIScreen.h>
+#import <UIKit/UITapGestureRecognizer.h>
+#import <UIKit/UITouch.h>
+#import <UIKit/UIView.h>
+#import <UIKit/UIViewController.h>
+#import <UIKit/UIWindow.h>
+#import <QuartzCore/QuartzCore.h>
+
+#include <algorithm>
+
+#include "nsWindow.h"
+#include "nsScreenManager.h"
+#include "nsAppShell.h"
+
+#include "nsWidgetsCID.h"
+#include "nsGfxCIID.h"
+
+#include "gfxQuartzSurface.h"
+#include "gfxUtils.h"
+#include "gfxImageSurface.h"
+#include "gfxContext.h"
+#include "nsRegion.h"
+#include "Layers.h"
+#include "nsTArray.h"
+
+#include "mozilla/BasicEvents.h"
+#include "mozilla/TouchEvents.h"
+#include "mozilla/Unused.h"
+
+#include "GeckoProfiler.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+using namespace mozilla::layers;
+
+#define ALOG(args...) fprintf(stderr, args); fprintf(stderr, "\n")
+
+static LayoutDeviceIntPoint
+UIKitPointsToDevPixels(CGPoint aPoint, CGFloat aBackingScale)
+{
+    return LayoutDeviceIntPoint(NSToIntRound(aPoint.x * aBackingScale),
+                                NSToIntRound(aPoint.y * aBackingScale));
+}
+
+static CGRect
+DevPixelsToUIKitPoints(const LayoutDeviceIntRect& aRect, CGFloat aBackingScale)
+{
+    return CGRectMake((CGFloat)aRect.x / aBackingScale,
+                      (CGFloat)aRect.y / aBackingScale,
+                      (CGFloat)aRect.width / aBackingScale,
+                      (CGFloat)aRect.height / aBackingScale);
+}
+
+// Used to retain a Cocoa object for the remainder of a method's execution.
+class nsAutoRetainUIKitObject {
+public:
+nsAutoRetainUIKitObject(id anObject)
+{
+  mObject = [anObject retain];
+}
+~nsAutoRetainUIKitObject()
+{
+  [mObject release];
+}
+private:
+  id mObject;  // [STRONG]
+};
+
+@interface ChildView : UIView
+{
+@public
+    nsWindow* mGeckoChild; // weak ref
+    BOOL mWaitingForPaint;
+    CFMutableDictionaryRef mTouches;
+    int mNextTouchID;
+}
+// sets up our view, attaching it to its owning gecko view
+- (id)initWithFrame:(CGRect)inFrame geckoChild:(nsWindow*)inChild;
+// Our Gecko child was Destroy()ed
+- (void)widgetDestroyed;
+// Tear down this ChildView
+- (void)delayedTearDown;
+- (void)sendMouseEvent:(EventMessage) aType point:(LayoutDeviceIntPoint)aPoint widget:(nsWindow*)aWindow;
+- (void)handleTap:(UITapGestureRecognizer *)sender;
+- (BOOL)isUsingMainThreadOpenGL;
+- (void)drawUsingOpenGL;
+- (void)drawUsingOpenGLCallback;
+- (void)sendTouchEvent:(EventMessage) aType touches:(NSSet*)aTouches widget:(nsWindow*)aWindow;
+// Event handling (UIResponder)
+- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event;
+- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event;
+- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event;
+- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event;
+@end
+
+@implementation ChildView
++ (Class)layerClass {
+    return [CAEAGLLayer class];
+}
+
+- (id)initWithFrame:(CGRect)inFrame geckoChild:(nsWindow*)inChild
+{
+    self.multipleTouchEnabled = YES;
+    if ((self = [super initWithFrame:inFrame])) {
+      mGeckoChild = inChild;
+    }
+    ALOG("[ChildView[%p] initWithFrame:] (mGeckoChild = %p)", (void*)self, (void*)mGeckoChild);
+    self.opaque = YES;
+    self.alpha = 1.0;
+
+    UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc]
+          initWithTarget:self action:@selector(handleTap:)];
+    tapRecognizer.numberOfTapsRequired = 1;
+    [self addGestureRecognizer:tapRecognizer];
+
+    mTouches = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, nullptr, nullptr);
+    mNextTouchID = 0;
+    return self;
+}
+
+- (void)widgetDestroyed
+{
+  mGeckoChild = nullptr;
+  CFRelease(mTouches);
+}
+
+- (void)delayedTearDown
+{
+  [self removeFromSuperview];
+  [self release];
+}
+
+- (void)sendMouseEvent:(EventMessage) aType point:(LayoutDeviceIntPoint)aPoint widget:(nsWindow*)aWindow
+{
+    WidgetMouseEvent event(true, aType, aWindow,
+                           WidgetMouseEvent::eReal, WidgetMouseEvent::eNormal);
+
+    event.mRefPoint = aPoint;
+    event.mClickCount = 1;
+    event.button = WidgetMouseEvent::eLeftButton;
+    event.mTime = PR_IntervalNow();
+    event.inputSource = nsIDOMMouseEvent::MOZ_SOURCE_UNKNOWN;
+
+    nsEventStatus status;
+    aWindow->DispatchEvent(&event, status);
+}
+
+- (void)handleTap:(UITapGestureRecognizer *)sender
+{
+    if (sender.state == UIGestureRecognizerStateEnded) {
+        ALOG("[ChildView[%p] handleTap]", self);
+        LayoutDeviceIntPoint lp = UIKitPointsToDevPixels([sender locationInView:self], [self contentScaleFactor]);
+        [self sendMouseEvent:eMouseMove point:lp widget:mGeckoChild];
+        [self sendMouseEvent:eMouseDown point:lp widget:mGeckoChild];
+        [self sendMouseEvent:eMouseUp point:lp widget:mGeckoChild];
+    }
+}
+
+- (void)sendTouchEvent:(EventMessage) aType touches:(NSSet*)aTouches widget:(nsWindow*)aWindow
+{
+    WidgetTouchEvent event(true, aType, aWindow);
+    //XXX: I think nativeEvent.timestamp * 1000 is probably usable here but
+    // I don't care that much right now.
+    event.mTime = PR_IntervalNow();
+    event.mTouches.SetCapacity(aTouches.count);
+    for (UITouch* touch in aTouches) {
+        LayoutDeviceIntPoint loc = UIKitPointsToDevPixels([touch locationInView:self], [self contentScaleFactor]);
+        LayoutDeviceIntPoint radius = UIKitPointsToDevPixels([touch majorRadius], [touch majorRadius]);
+        void* value;
+        if (!CFDictionaryGetValueIfPresent(mTouches, touch, (const void**)&value)) {
+            // This shouldn't happen.
+            NS_ASSERTION(false, "Got a touch that we didn't know about");
+            continue;
+        }
+        int id = reinterpret_cast<int>(value);
+        RefPtr<Touch> t = new Touch(id, loc, radius, 0.0f, 1.0f);
+        event.mRefPoint = loc;
+        event.mTouches.AppendElement(t);
+    }
+    aWindow->DispatchInputEvent(&event);
+}
+
+- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
+{
+    ALOG("[ChildView[%p] touchesBegan", self);
+    if (!mGeckoChild)
+        return;
+
+    for (UITouch* touch : touches) {
+        CFDictionaryAddValue(mTouches, touch, (void*)mNextTouchID);
+        mNextTouchID++;
+    }
+    [self sendTouchEvent:eTouchStart
+                 touches:[event allTouches]
+                  widget:mGeckoChild];
+}
+
+- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
+{
+    ALOG("[ChildView[%p] touchesCancelled", self);
+    [self sendTouchEvent:eTouchCancel touches:touches widget:mGeckoChild];
+    for (UITouch* touch : touches) {
+        CFDictionaryRemoveValue(mTouches, touch);
+    }
+    if (CFDictionaryGetCount(mTouches) == 0) {
+        mNextTouchID = 0;
+    }
+}
+
+- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
+{
+    ALOG("[ChildView[%p] touchesEnded", self);
+    if (!mGeckoChild)
+        return;
+
+    [self sendTouchEvent:eTouchEnd touches:touches widget:mGeckoChild];
+    for (UITouch* touch : touches) {
+        CFDictionaryRemoveValue(mTouches, touch);
+    }
+    if (CFDictionaryGetCount(mTouches) == 0) {
+        mNextTouchID = 0;
+    }
+}
+
+- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
+{
+    ALOG("[ChildView[%p] touchesMoved", self);
+    if (!mGeckoChild)
+        return;
+
+    [self sendTouchEvent:eTouchMove
+                 touches:[event allTouches]
+                  widget:mGeckoChild];
+}
+
+- (void)setNeedsDisplayInRect:(CGRect)aRect
+{
+    if ([self isUsingMainThreadOpenGL]) {
+    // Draw without calling drawRect. This prevent us from
+    // needing to access the normal window buffer surface unnecessarily, so we
+    // waste less time synchronizing the two surfaces.
+    if (!mWaitingForPaint) {
+      mWaitingForPaint = YES;
+      // Use NSRunLoopCommonModes instead of the default NSDefaultRunLoopMode
+      // so that the timer also fires while a native menu is open.
+      [self performSelector:@selector(drawUsingOpenGLCallback)
+                 withObject:nil
+                 afterDelay:0
+                    inModes:[NSArray arrayWithObject:NSRunLoopCommonModes]];
+    }
+  }
+}
+
+- (BOOL)isUsingMainThreadOpenGL
+{
+  if (!mGeckoChild || ![self window])
+    return NO;
+
+  return mGeckoChild->GetLayerManager(nullptr)->GetBackendType() == mozilla::layers::LayersBackend::LAYERS_OPENGL;
+}
+
+- (void)drawUsingOpenGL
+{
+    ALOG("drawUsingOpenGL");
+  PROFILER_LABEL("ChildView", "drawUsingOpenGL",
+    js::ProfileEntry::Category::GRAPHICS);
+
+  if (!mGeckoChild->IsVisible())
+    return;
+
+  mWaitingForPaint = NO;
+
+  LayoutDeviceIntRect geckoBounds = mGeckoChild->GetBounds();
+  LayoutDeviceIntRegion region(geckoBounds);
+
+  mGeckoChild->PaintWindow(region);
+}
+
+// Called asynchronously after setNeedsDisplay in order to avoid entering the
+// normal drawing machinery.
+- (void)drawUsingOpenGLCallback
+{
+  if (mWaitingForPaint) {
+    [self drawUsingOpenGL];
+  }
+}
+
+// The display system has told us that a portion of our view is dirty. Tell
+// gecko to paint it
+- (void)drawRect:(CGRect)aRect
+{
+    CGContextRef cgContext = UIGraphicsGetCurrentContext();
+    [self drawRect:aRect inContext:cgContext];
+}
+
+- (void)drawRect:(CGRect)aRect inContext:(CGContextRef)aContext
+{
+#ifdef DEBUG_UPDATE
+  LayoutDeviceIntRect geckoBounds = mGeckoChild->GetBounds();
+
+  fprintf (stderr, "---- Update[%p][%p] [%f %f %f %f] cgc: %p\n  gecko bounds: [%d %d %d %d]\n",
+           self, mGeckoChild,
+           aRect.origin.x, aRect.origin.y, aRect.size.width, aRect.size.height, aContext,
+           geckoBounds.x, geckoBounds.y, geckoBounds.width, geckoBounds.height);
+
+  CGAffineTransform xform = CGContextGetCTM(aContext);
+  fprintf (stderr, "  xform in: [%f %f %f %f %f %f]\n", xform.a, xform.b, xform.c, xform.d, xform.tx, xform.ty);
+#endif
+
+  if (true) {
+    // For Gecko-initiated repaints in OpenGL mode, drawUsingOpenGL is
+    // directly called from a delayed perform callback - without going through
+    // drawRect.
+    // Paints that come through here are triggered by something that Cocoa
+    // controls, for example by window resizing or window focus changes.
+
+    // Do GL composition and return.
+    [self drawUsingOpenGL];
+    return;
+  }
+  PROFILER_LABEL("ChildView", "drawRect",
+    js::ProfileEntry::Category::GRAPHICS);
+
+  // The CGContext that drawRect supplies us with comes with a transform that
+  // scales one user space unit to one Cocoa point, which can consist of
+  // multiple dev pixels. But Gecko expects its supplied context to be scaled
+  // to device pixels, so we need to reverse the scaling.
+  double scale = mGeckoChild->BackingScaleFactor();
+  CGContextSaveGState(aContext);
+  CGContextScaleCTM(aContext, 1.0 / scale, 1.0 / scale);
+
+  CGSize viewSize = [self bounds].size;
+  gfx::IntSize backingSize(viewSize.width * scale, viewSize.height * scale);
+
+  CGContextSaveGState(aContext);
+
+  LayoutDeviceIntRegion region =
+    LayoutDeviceIntRect(NSToIntRound(aRect.origin.x * scale),
+                        NSToIntRound(aRect.origin.y * scale),
+                        NSToIntRound(aRect.size.width * scale),
+                        NSToIntRound(aRect.size.height * scale));
+
+  // Create Cairo objects.
+  RefPtr<gfxQuartzSurface> targetSurface;
+
+  RefPtr<gfxContext> targetContext;
+  if (gfxPlatform::GetPlatform()->SupportsAzureContentForType(gfx::BackendType::CAIRO)) {
+    // This is dead code unless you mess with prefs, but keep it around for
+    // debugging.
+    targetSurface = new gfxQuartzSurface(aContext, backingSize);
+    targetSurface->SetAllowUseAsSource(false);
+    RefPtr<gfx::DrawTarget> dt =
+      gfxPlatform::GetPlatform()->CreateDrawTargetForSurface(targetSurface,
+                                                             backingSize);
+    if (!dt || !dt->IsValid()) {
+        gfxDevCrash(mozilla::gfx::LogReason::InvalidContext) << "Window context problem 2 " << backingSize;
+        return;
+    }
+    dt->AddUserData(&gfxContext::sDontUseAsSourceKey, dt, nullptr);
+    targetContext = gfxContext::CreateOrNull(dt);
+  } else {
+    MOZ_ASSERT_UNREACHABLE("COREGRAPHICS is the only supported backend");
+  }
+  MOZ_ASSERT(targetContext); // already checked for valid draw targets above
+
+  // Set up the clip region.
+  targetContext->NewPath();
+  for (auto iter = region.RectIter(); !iter.Done(); iter.Next()) {
+    const LayoutDeviceIntRect& r = iter.Get();
+    targetContext->Rectangle(gfxRect(r.x, r.y, r.width, r.height));
+  }
+  targetContext->Clip();
+
+  //nsAutoRetainCocoaObject kungFuDeathGrip(self);
+  bool painted = false;
+  if (mGeckoChild->GetLayerManager()->GetBackendType() == LayersBackend::LAYERS_BASIC) {
+    nsBaseWidget::AutoLayerManagerSetup
+      setupLayerManager(mGeckoChild, targetContext, BufferMode::BUFFER_NONE);
+    painted = mGeckoChild->PaintWindow(region);
+  } else if (mGeckoChild->GetLayerManager()->GetBackendType() == LayersBackend::LAYERS_CLIENT) {
+    // We only need this so that we actually get DidPaintWindow fired
+    painted = mGeckoChild->PaintWindow(region);
+  }
+
+  targetContext = nullptr;
+  targetSurface = nullptr;
+
+  CGContextRestoreGState(aContext);
+
+  // Undo the scale transform so that from now on the context is in
+  // CocoaPoints again.
+  CGContextRestoreGState(aContext);
+  if (!painted && [self isOpaque]) {
+    // Gecko refused to draw, but we've claimed to be opaque, so we have to
+    // draw something--fill with white.
+    CGContextSetRGBFillColor(aContext, 1, 1, 1, 1);
+    CGContextFillRect(aContext, aRect);
+  }
+
+#ifdef DEBUG_UPDATE
+  fprintf (stderr, "---- update done ----\n");
+
+#if 0
+  CGContextSetRGBStrokeColor (aContext,
+                            ((((unsigned long)self) & 0xff)) / 255.0,
+                            ((((unsigned long)self) & 0xff00) >> 8) / 255.0,
+                            ((((unsigned long)self) & 0xff0000) >> 16) / 255.0,
+                            0.5);
+#endif
+  CGContextSetRGBStrokeColor(aContext, 1, 0, 0, 0.8);
+  CGContextSetLineWidth(aContext, 4.0);
+  CGContextStrokeRect(aContext, aRect);
+#endif
+}
+@end
+
+NS_IMPL_ISUPPORTS_INHERITED0(nsWindow, Inherited)
+
+nsWindow::nsWindow()
+: mNativeView(nullptr),
+  mVisible(false),
+  mParent(nullptr)
+{
+}
+
+nsWindow::~nsWindow()
+{
+    [mNativeView widgetDestroyed]; // Safe if mNativeView is nil.
+    TearDownView(); // Safe if called twice.
+}
+
+void nsWindow::TearDownView()
+{
+  if (!mNativeView)
+    return;
+
+  [mNativeView performSelectorOnMainThread:@selector(delayedTearDown) withObject:nil waitUntilDone:false];
+  mNativeView = nil;
+}
+
+bool
+nsWindow::IsTopLevel()
+{
+    return mWindowType == eWindowType_toplevel ||
+        mWindowType == eWindowType_dialog ||
+        mWindowType == eWindowType_invisible;
+}
+
+//
+// nsIWidget
+//
+
+nsresult
+nsWindow::Create(nsIWidget* aParent,
+                 nsNativeWidget aNativeParent,
+                 const LayoutDeviceIntRect& aRect,
+                 nsWidgetInitData* aInitData)
+{
+    ALOG("nsWindow[%p]::Create %p/%p [%d %d %d %d]", (void*)this, (void*)aParent, (void*)aNativeParent, aRect.x, aRect.y, aRect.width, aRect.height);
+    nsWindow* parent = (nsWindow*) aParent;
+    ChildView* nativeParent = (ChildView*)aNativeParent;
+
+    if (parent == nullptr && nativeParent)
+        parent = nativeParent->mGeckoChild;
+    if (parent && nativeParent == nullptr)
+        nativeParent = parent->mNativeView;
+
+    // for toplevel windows, bounds are fixed to full screen size
+    if (parent == nullptr) {
+        if (nsAppShell::gWindow == nil) {
+            mBounds = UIKitScreenManager::GetBounds();
+        } else {
+            CGRect cgRect = [nsAppShell::gWindow bounds];
+            mBounds.x = cgRect.origin.x;
+            mBounds.y = cgRect.origin.y;
+            mBounds.width = cgRect.size.width;
+            mBounds.height = cgRect.size.height;
+        }
+    } else {
+        mBounds = aRect;
+    }
+
+    ALOG("nsWindow[%p]::Create bounds: %d %d %d %d", (void*)this,
+         mBounds.x, mBounds.y, mBounds.width, mBounds.height);
+
+    // Set defaults which can be overriden from aInitData in BaseCreate
+    mWindowType = eWindowType_toplevel;
+    mBorderStyle = eBorderStyle_default;
+
+    Inherited::BaseCreate(aParent, aInitData);
+
+    NS_ASSERTION(IsTopLevel() || parent, "non top level window doesn't have a parent!");
+
+    mNativeView = [[ChildView alloc] initWithFrame:DevPixelsToUIKitPoints(mBounds, BackingScaleFactor()) geckoChild:this];
+    mNativeView.hidden = YES;
+
+    if (parent) {
+        parent->mChildren.AppendElement(this);
+        mParent = parent;
+    }
+
+    if (nativeParent) {
+        [nativeParent addSubview:mNativeView];
+    } else if (nsAppShell::gWindow) {
+        [nsAppShell::gWindow.rootViewController.view addSubview:mNativeView];
+    }
+    else {
+        [nsAppShell::gTopLevelViews addObject:mNativeView];
+    }
+
+  return NS_OK;
+}
+
+void
+nsWindow::Destroy()
+{
+    for (uint32_t i = 0; i < mChildren.Length(); ++i) {
+        // why do we still have children?
+        mChildren[i]->SetParent(nullptr);
+    }
+
+    if (mParent)
+        mParent->mChildren.RemoveElement(this);
+
+    [mNativeView widgetDestroyed];
+
+    nsBaseWidget::Destroy();
+
+    //ReportDestroyEvent();
+
+    TearDownView();
+
+    nsBaseWidget::OnDestroy();
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindow::ConfigureChildren(const nsTArray<nsIWidget::Configuration>& config)
+{
+    for (uint32_t i = 0; i < config.Length(); ++i) {
+        nsWindow *childWin = (nsWindow*) config[i].mChild.get();
+        childWin->Resize(config[i].mBounds.x,
+                         config[i].mBounds.y,
+                         config[i].mBounds.width,
+                         config[i].mBounds.height,
+                         false);
+    }
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindow::Show(bool aState)
+{
+  if (aState != mVisible) {
+      mNativeView.hidden = aState ? NO : YES;
+      if (aState) {
+          UIView* parentView = mParent ? mParent->mNativeView : nsAppShell::gWindow.rootViewController.view;
+          [parentView bringSubviewToFront:mNativeView];
+          [mNativeView setNeedsDisplay];
+      }
+      mVisible = aState;
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindow::Move(double aX, double aY)
+{
+  if (!mNativeView || (mBounds.x == aX && mBounds.y == aY))
+    return NS_OK;
+
+  //XXX: handle this
+  // The point we have is in Gecko coordinates (origin top-left). Convert
+  // it to Cocoa ones (origin bottom-left).
+  mBounds.x = aX;
+  mBounds.y = aY;
+
+  mNativeView.frame = DevPixelsToUIKitPoints(mBounds, BackingScaleFactor());
+
+  if (mVisible)
+    [mNativeView setNeedsDisplay];
+
+  ReportMoveEvent();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindow::Resize(double aX, double aY,
+                 double aWidth, double aHeight,
+                 bool aRepaint)
+{
+    BOOL isMoving = (mBounds.x != aX || mBounds.y != aY);
+    BOOL isResizing = (mBounds.width != aWidth || mBounds.height != aHeight);
+    if (!mNativeView || (!isMoving && !isResizing))
+        return NS_OK;
+
+    if (isMoving) {
+        mBounds.x = aX;
+        mBounds.y = aY;
+    }
+    if (isResizing) {
+        mBounds.width  = aWidth;
+        mBounds.height  = aHeight;
+    }
+
+    [mNativeView setFrame:DevPixelsToUIKitPoints(mBounds, BackingScaleFactor())];
+
+    if (mVisible && aRepaint)
+        [mNativeView setNeedsDisplay];
+
+    if (isMoving)
+        ReportMoveEvent();
+
+    if (isResizing)
+        ReportSizeEvent();
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP nsWindow::Resize(double aWidth, double aHeight, bool aRepaint)
+{
+    if (!mNativeView || (mBounds.width == aWidth && mBounds.height == aHeight))
+        return NS_OK;
+
+    mBounds.width  = aWidth;
+    mBounds.height = aHeight;
+
+    [mNativeView setFrame:DevPixelsToUIKitPoints(mBounds, BackingScaleFactor())];
+
+    if (mVisible && aRepaint)
+        [mNativeView setNeedsDisplay];
+
+    ReportSizeEvent();
+
+    return NS_OK;
+}
+
+void
+nsWindow::SetSizeMode(nsSizeMode aMode)
+{
+    if (aMode == static_cast<int32_t>(mSizeMode)) {
+        return;
+    }
+
+    mSizeMode = static_cast<nsSizeMode>(aMode);
+    if (aMode == nsSizeMode_Maximized || aMode == nsSizeMode_Fullscreen) {
+        // Resize to fill screen
+        nsBaseWidget::InfallibleMakeFullScreen(true);
+    }
+    ReportSizeModeEvent(aMode);
+}
+
+NS_IMETHODIMP
+nsWindow::Invalidate(const LayoutDeviceIntRect& aRect)
+{
+  if (!mNativeView || !mVisible)
+    return NS_OK;
+
+  MOZ_RELEASE_ASSERT(GetLayerManager()->GetBackendType() != LayersBackend::LAYERS_CLIENT,
+                     "Shouldn't need to invalidate with accelerated OMTC layers!");
+
+
+  [mNativeView setNeedsLayout];
+  [mNativeView setNeedsDisplayInRect:DevPixelsToUIKitPoints(mBounds, BackingScaleFactor())];
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindow::SetFocus(bool aRaise)
+{
+  [[mNativeView window] makeKeyWindow];
+  [mNativeView becomeFirstResponder];
+  return NS_OK;
+}
+
+void nsWindow::WillPaintWindow()
+{
+  if (mWidgetListener) {
+    mWidgetListener->WillPaintWindow(this);
+  }
+}
+
+bool nsWindow::PaintWindow(LayoutDeviceIntRegion aRegion)
+{
+  if (!mWidgetListener)
+    return false;
+
+  bool returnValue = false;
+  returnValue = mWidgetListener->PaintWindow(this, aRegion);
+
+  if (mWidgetListener) {
+    mWidgetListener->DidPaintWindow();
+  }
+
+  return returnValue;
+}
+
+void nsWindow::ReportMoveEvent()
+{
+    NotifyWindowMoved(mBounds.x, mBounds.y);
+}
+
+void nsWindow::ReportSizeModeEvent(nsSizeMode aMode)
+{
+    if (mWidgetListener) {
+        // This is terrible.
+        nsSizeMode theMode;
+        switch (aMode) {
+        case nsSizeMode_Maximized:
+            theMode = nsSizeMode_Maximized;
+            break;
+        case nsSizeMode_Fullscreen:
+            theMode = nsSizeMode_Fullscreen;
+            break;
+        default:
+            return;
+        }
+        mWidgetListener->SizeModeChanged(theMode);
+    }
+}
+
+void nsWindow::ReportSizeEvent()
+{
+    if (mWidgetListener) {
+        LayoutDeviceIntRect innerBounds = GetClientBounds();
+        mWidgetListener->WindowResized(this, innerBounds.width, innerBounds.height);
+    }
+}
+
+LayoutDeviceIntRect
+nsWindow::GetScreenBounds()
+{
+    return LayoutDeviceIntRect(WidgetToScreenOffset(), mBounds.Size());
+}
+
+LayoutDeviceIntPoint nsWindow::WidgetToScreenOffset()
+{
+    LayoutDeviceIntPoint offset(0, 0);
+    if (mParent) {
+        offset = mParent->WidgetToScreenOffset();
+    }
+
+    CGPoint temp = [mNativeView convertPoint:temp toView:nil];
+
+    if (!mParent && nsAppShell::gWindow) {
+        // convert to screen coords
+        temp = [nsAppShell::gWindow convertPoint:temp toWindow:nil];
+    }
+
+    offset.x += temp.x;
+    offset.y += temp.y;
+
+    return offset;
+}
+
+NS_IMETHODIMP
+nsWindow::DispatchEvent(mozilla::WidgetGUIEvent* aEvent,
+                        nsEventStatus& aStatus)
+{
+  aStatus = nsEventStatus_eIgnore;
+  nsCOMPtr<nsIWidget> kungFuDeathGrip(aEvent->mWidget);
+
+  if (mWidgetListener)
+    aStatus = mWidgetListener->HandleEvent(aEvent, mUseAttachedEvents);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP_(void)
+nsWindow::SetInputContext(const InputContext& aContext,
+                          const InputContextAction& aAction)
+{
+    //TODO: actually show VKB
+    mInputContext = aContext;
+}
+
+NS_IMETHODIMP_(mozilla::widget::InputContext)
+nsWindow::GetInputContext()
+{
+    return mInputContext;
+}
+
+void
+nsWindow::SetBackgroundColor(const nscolor &aColor)
+{
+    mNativeView.backgroundColor = [UIColor colorWithRed:NS_GET_R(aColor)
+                                   green:NS_GET_G(aColor)
+                                   blue:NS_GET_B(aColor)
+                                   alpha:NS_GET_A(aColor)];
+}
+
+void* nsWindow::GetNativeData(uint32_t aDataType)
+{
+  void* retVal = nullptr;
+
+  switch (aDataType)
+  {
+    case NS_NATIVE_WIDGET:
+    case NS_NATIVE_DISPLAY:
+      retVal = (void*)mNativeView;
+      break;
+
+    case NS_NATIVE_WINDOW:
+      retVal = [mNativeView window];
+      break;
+
+    case NS_NATIVE_GRAPHIC:
+      NS_ERROR("Requesting NS_NATIVE_GRAPHIC on a UIKit child view!");
+      break;
+
+    case NS_NATIVE_OFFSETX:
+      retVal = 0;
+      break;
+
+    case NS_NATIVE_OFFSETY:
+      retVal = 0;
+      break;
+
+    case NS_NATIVE_PLUGIN_PORT:
+        // not implemented
+        break;
+
+    case NS_RAW_NATIVE_IME_CONTEXT:
+      retVal = GetPseudoIMEContext();
+      if (retVal) {
+        break;
+      }
+      retVal = NS_ONLY_ONE_NATIVE_IME_CONTEXT;
+      break;
+  }
+
+  return retVal;
+}
+
+CGFloat
+nsWindow::BackingScaleFactor()
+{
+    if (mNativeView) {
+        return [mNativeView contentScaleFactor];
+    }
+    return [UIScreen mainScreen].scale;
+}
+
+int32_t
+nsWindow::RoundsWidgetCoordinatesTo()
+{
+  if (BackingScaleFactor() == 2.0) {
+    return 2;
+  }
+  return 1;
+}