Add m-esr52 at 52.6.0

1 files changed, 1588 insertions, 0 deletions

diff --git a/layout/base/nsPresContext.h b/layout/base/nsPresContext.h
new file mode 100644
index 0000000000..4fdc60a2ea
--- /dev/null
+++ b/layout/base/nsPresContext.h
@@ -0,0 +1,1588 @@
+/* -*- 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/. */
+
+/* a presentation of a document, part 1 */
+
+#ifndef nsPresContext_h___
+#define nsPresContext_h___
+
+#include "mozilla/Attributes.h"
+#include "mozilla/WeakPtr.h"
+#include "nsColor.h"
+#include "nsCoord.h"
+#include "nsCOMPtr.h"
+#include "nsIPresShell.h"
+#include "nsRect.h"
+#include "nsFont.h"
+#include "gfxFontConstants.h"
+#include "nsIAtom.h"
+#include "nsIObserver.h"
+#include "nsITimer.h"
+#include "nsCRT.h"
+#include "nsIWidgetListener.h"
+#include "FramePropertyTable.h"
+#include "nsGkAtoms.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsChangeHint.h"
+#include <algorithm>
+// This also pulls in gfxTypes.h, which we cannot include directly.
+#include "gfxRect.h"
+#include "nsTArray.h"
+#include "nsAutoPtr.h"
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/AppUnits.h"
+#include "prclist.h"
+#include "nsThreadUtils.h"
+#include "ScrollbarStyles.h"
+#include "nsIMessageManager.h"
+#include "mozilla/RestyleLogging.h"
+#include "Units.h"
+#include "mozilla/RestyleManagerHandle.h"
+#include "prenv.h"
+#include "mozilla/StaticPresData.h"
+#include "mozilla/StyleBackendType.h"
+
+class nsAString;
+class nsIPrintSettings;
+class nsDocShell;
+class nsIDocShell;
+class nsIDocument;
+class nsILanguageAtomService;
+class nsITheme;
+class nsIContent;
+class nsIFrame;
+class nsFrameManager;
+class nsILinkHandler;
+class nsIAtom;
+class nsIRunnable;
+class gfxUserFontEntry;
+class gfxUserFontSet;
+class gfxTextPerfMetrics;
+class nsPluginFrame;
+class nsTransitionManager;
+class nsAnimationManager;
+class nsRefreshDriver;
+class nsIWidget;
+class nsDeviceContext;
+class gfxMissingFontRecorder;
+
+namespace mozilla {
+class EffectCompositor;
+class EventStateManager;
+class CounterStyleManager;
+namespace layers {
+class ContainerLayer;
+class LayerManager;
+} // namespace layers
+namespace dom {
+class Element;
+} // namespace dom
+} // namespace mozilla
+
+// supported values for cached bool types
+enum nsPresContext_CachedBoolPrefType {
+  kPresContext_UseDocumentFonts = 1,
+  kPresContext_UnderlineLinks
+};
+
+// supported values for cached integer pref types
+enum nsPresContext_CachedIntPrefType {
+  kPresContext_ScrollbarSide = 1,
+  kPresContext_BidiDirection
+};
+
+// IDs for the default variable and fixed fonts (not to be changed, see nsFont.h)
+// To be used for Get/SetDefaultFont(). The other IDs in nsFont.h are also supported.
+const uint8_t kPresContext_DefaultVariableFont_ID = 0x00; // kGenericFont_moz_variable
+const uint8_t kPresContext_DefaultFixedFont_ID    = 0x01; // kGenericFont_moz_fixed
+
+#ifdef DEBUG
+struct nsAutoLayoutPhase;
+
+enum nsLayoutPhase {
+  eLayoutPhase_Paint,
+  eLayoutPhase_Reflow,
+  eLayoutPhase_FrameC,
+  eLayoutPhase_COUNT
+};
+#endif
+
+class nsInvalidateRequestList {
+public:
+  struct Request {
+    nsRect   mRect;
+    uint32_t mFlags;
+  };
+
+  void TakeFrom(nsInvalidateRequestList* aList)
+  {
+    mRequests.AppendElements(mozilla::Move(aList->mRequests));
+  }
+  bool IsEmpty() { return mRequests.IsEmpty(); }
+
+  nsTArray<Request> mRequests;
+};
+
+/* Used by nsPresContext::HasAuthorSpecifiedRules */
+#define NS_AUTHOR_SPECIFIED_BACKGROUND      (1 << 0)
+#define NS_AUTHOR_SPECIFIED_BORDER          (1 << 1)
+#define NS_AUTHOR_SPECIFIED_PADDING         (1 << 2)
+#define NS_AUTHOR_SPECIFIED_TEXT_SHADOW     (1 << 3)
+
+class nsRootPresContext;
+
+// An interface for presentation contexts. Presentation contexts are
+// objects that provide an outer context for a presentation shell.
+
+class nsPresContext : public nsIObserver,
+                      public mozilla::SupportsWeakPtr<nsPresContext> {
+public:
+  typedef mozilla::FramePropertyTable FramePropertyTable;
+  typedef mozilla::LangGroupFontPrefs LangGroupFontPrefs;
+  typedef mozilla::ScrollbarStyles ScrollbarStyles;
+  typedef mozilla::StaticPresData StaticPresData;
+
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_NSIOBSERVER
+  NS_DECL_AND_IMPL_ZEROING_OPERATOR_NEW
+  NS_DECL_CYCLE_COLLECTION_CLASS(nsPresContext)
+  MOZ_DECLARE_WEAKREFERENCE_TYPENAME(nsPresContext)
+
+  enum nsPresContextType {
+    eContext_Galley,       // unpaginated screen presentation
+    eContext_PrintPreview, // paginated screen presentation
+    eContext_Print,        // paginated printer presentation
+    eContext_PageLayout    // paginated & editable.
+  };
+
+  nsPresContext(nsIDocument* aDocument, nsPresContextType aType);
+
+  /**
+   * Initialize the presentation context from a particular device.
+   */
+  nsresult Init(nsDeviceContext* aDeviceContext);
+
+  /**
+   * Set and detach presentation shell that this context is bound to.
+   * A presentation context may only be bound to a single shell.
+   */
+  void AttachShell(nsIPresShell* aShell, mozilla::StyleBackendType aBackendType);
+  void DetachShell();
+
+
+  nsPresContextType Type() const { return mType; }
+
+  /**
+   * Get the PresentationShell that this context is bound to.
+   */
+  nsIPresShell* PresShell() const
+  {
+    NS_ASSERTION(mShell, "Null pres shell");
+    return mShell;
+  }
+
+  nsIPresShell* GetPresShell() const { return mShell; }
+
+  /**
+   * Returns the parent prescontext for this one. Returns null if this is a
+   * root.
+   */
+  nsPresContext* GetParentPresContext();
+
+  /**
+   * Returns the prescontext of the toplevel content document that contains
+   * this presentation, or null if there isn't one.
+   */
+  nsPresContext* GetToplevelContentDocumentPresContext();
+
+  /**
+   * Returns the nearest widget for the root frame of this.
+   *
+   * @param aOffset     If non-null the offset from the origin of the root
+   *                    frame's view to the widget's origin (usually positive)
+   *                    expressed in appunits of this will be returned in
+   *                    aOffset.
+   */
+  nsIWidget* GetNearestWidget(nsPoint* aOffset = nullptr);
+
+  /**
+   * Returns the root widget for this.
+   * Note that the widget is a mediater with IME.
+   */
+  nsIWidget* GetRootWidget();
+
+  /**
+   * Return the presentation context for the root of the view manager
+   * hierarchy that contains this presentation context, or nullptr if it can't
+   * be found (e.g. it's detached).
+   */
+  nsRootPresContext* GetRootPresContext();
+
+  virtual bool IsRoot() { return false; }
+
+  nsIDocument* Document() const
+  {
+      NS_ASSERTION(!mShell || !mShell->GetDocument() ||
+                   mShell->GetDocument() == mDocument,
+                   "nsPresContext doesn't have the same document as nsPresShell!");
+      return mDocument;
+  }
+
+#ifdef MOZILLA_INTERNAL_API
+  mozilla::StyleSetHandle StyleSet() { return GetPresShell()->StyleSet(); }
+
+  nsFrameManager* FrameManager()
+    { return PresShell()->FrameManager(); }
+
+  nsCSSFrameConstructor* FrameConstructor()
+    { return PresShell()->FrameConstructor(); }
+
+  mozilla::EffectCompositor* EffectCompositor() { return mEffectCompositor; }
+  nsTransitionManager* TransitionManager() { return mTransitionManager; }
+  nsAnimationManager* AnimationManager() { return mAnimationManager; }
+
+  nsRefreshDriver* RefreshDriver() { return mRefreshDriver; }
+
+  mozilla::RestyleManagerHandle RestyleManager() {
+    MOZ_ASSERT(mRestyleManager);
+    return mRestyleManager;
+  }
+
+  mozilla::CounterStyleManager* CounterStyleManager() {
+    return mCounterStyleManager;
+  }
+#endif
+
+  /**
+   * Rebuilds all style data by throwing out the old rule tree and
+   * building a new one, and additionally applying aExtraHint (which
+   * must not contain nsChangeHint_ReconstructFrame) to the root frame.
+   * For aRestyleHint, see RestyleManager::RebuildAllStyleData.
+   * Also rebuild the user font set and counter style manager.
+   */
+  void RebuildAllStyleData(nsChangeHint aExtraHint, nsRestyleHint aRestyleHint);
+  /**
+   * Just like RebuildAllStyleData, except (1) asynchronous and (2) it
+   * doesn't rebuild the user font set.
+   */
+  void PostRebuildAllStyleDataEvent(nsChangeHint aExtraHint,
+                                    nsRestyleHint aRestyleHint);
+
+  /**
+   * Handle changes in the values of media features (used in media
+   * queries).
+   *
+   * There are three sensible values to use for aRestyleHint:
+   *  * nsRestyleHint(0) to rebuild style data, with rerunning of
+   *    selector matching, only if media features have changed
+   *  * eRestyle_ForceDescendants to force rebuilding of style data (but
+   *    still only rerun selector matching if media query results have
+   *    changed).  (RebuildAllStyleData always adds
+   *    eRestyle_ForceDescendants internally, so here we're only using
+   *    it to distinguish from nsRestyleHint(0) whether we need to call
+   *    RebuildAllStyleData at all.)
+   *  * eRestyle_Subtree to force rebuilding of style data with
+   *    rerunning of selector matching
+   *
+   * For aChangeHint, see RestyleManager::RebuildAllStyleData.  (Passing
+   * a nonzero aChangeHint forces rebuilding style data even if
+   * nsRestyleHint(0) is passed.)
+   */
+  void MediaFeatureValuesChanged(nsRestyleHint aRestyleHint,
+                                 nsChangeHint aChangeHint = nsChangeHint(0));
+  /**
+   * Calls MediaFeatureValuesChanged for this pres context and all descendant
+   * subdocuments that have a pres context. This should be used for media
+   * features that must be updated in all subdocuments e.g. display-mode.
+   */
+  void MediaFeatureValuesChangedAllDocuments(nsRestyleHint aRestyleHint,
+                                             nsChangeHint aChangeHint = nsChangeHint(0));
+
+  void PostMediaFeatureValuesChangedEvent();
+  void HandleMediaFeatureValuesChangedEvent();
+  void FlushPendingMediaFeatureValuesChanged() {
+    if (mPendingMediaFeatureValuesChanged)
+      MediaFeatureValuesChanged(nsRestyleHint(0));
+  }
+
+  /**
+   * Updates the size mode on all remote children and recursively notifies this
+   * document and all subdocuments (including remote children) that a media
+   * feature value has changed.
+   */
+  void SizeModeChanged(nsSizeMode aSizeMode);
+
+  /**
+   * Access compatibility mode for this context.  This is the same as
+   * our document's compatibility mode.
+   */
+  nsCompatibility CompatibilityMode() const;
+
+  /**
+   * Notify the context that the document's compatibility mode has changed
+   */
+  void CompatibilityModeChanged();
+
+  /**
+   * Access the image animation mode for this context
+   */
+  uint16_t     ImageAnimationMode() const { return mImageAnimationMode; }
+  virtual void SetImageAnimationModeExternal(uint16_t aMode);
+  void SetImageAnimationModeInternal(uint16_t aMode);
+#ifdef MOZILLA_INTERNAL_API
+  void SetImageAnimationMode(uint16_t aMode)
+  { SetImageAnimationModeInternal(aMode); }
+#else
+  void SetImageAnimationMode(uint16_t aMode)
+  { SetImageAnimationModeExternal(aMode); }
+#endif
+
+  /**
+   * Get medium of presentation
+   */
+  nsIAtom* Medium() {
+    if (!mIsEmulatingMedia)
+      return mMedium;
+    return mMediaEmulated;
+  }
+
+  /*
+   * Render the document as if being viewed on a device with the specified
+   * media type.
+   */
+  void EmulateMedium(const nsAString& aMediaType);
+
+  /*
+   * Restore the viewer's natural medium
+   */
+  void StopEmulatingMedium();
+
+  void* AllocateFromShell(size_t aSize)
+  {
+    if (mShell)
+      return mShell->AllocateMisc(aSize);
+    return nullptr;
+  }
+
+  void FreeToShell(size_t aSize, void* aFreeChunk)
+  {
+    NS_ASSERTION(mShell, "freeing after shutdown");
+    if (mShell)
+      mShell->FreeMisc(aSize, aFreeChunk);
+  }
+
+  /**
+   * Get the default font for the given language and generic font ID.
+   * If aLanguage is nullptr, the document's language is used.
+   *
+   * See the comment in StaticPresData::GetDefaultFont.
+   */
+  const nsFont* GetDefaultFont(uint8_t aFontID,
+                               nsIAtom *aLanguage) const
+  {
+    nsIAtom* lang = aLanguage ? aLanguage : mLanguage.get();
+    return StaticPresData::Get()->GetDefaultFontHelper(aFontID, lang,
+                                                       GetFontPrefsForLang(lang));
+  }
+
+  /** Get a cached boolean pref, by its type */
+  // *  - initially created for bugs 31816, 20760, 22963
+  bool GetCachedBoolPref(nsPresContext_CachedBoolPrefType aPrefType) const
+  {
+    // If called with a constant parameter, the compiler should optimize
+    // this switch statement away.
+    switch (aPrefType) {
+    case kPresContext_UseDocumentFonts:
+      return mUseDocumentFonts;
+    case kPresContext_UnderlineLinks:
+      return mUnderlineLinks;
+    default:
+      NS_ERROR("Invalid arg passed to GetCachedBoolPref");
+    }
+
+    return false;
+  }
+
+  /** Get a cached integer pref, by its type */
+  // *  - initially created for bugs 30910, 61883, 74186, 84398
+  int32_t GetCachedIntPref(nsPresContext_CachedIntPrefType aPrefType) const
+  {
+    // If called with a constant parameter, the compiler should optimize
+    // this switch statement away.
+    switch (aPrefType) {
+    case kPresContext_ScrollbarSide:
+      return mPrefScrollbarSide;
+    case kPresContext_BidiDirection:
+      return mPrefBidiDirection;
+    default:
+      NS_ERROR("invalid arg passed to GetCachedIntPref");
+    }
+
+    return false;
+  }
+
+  /**
+   * Get the default colors
+   */
+  nscolor DefaultColor() const { return mDefaultColor; }
+  nscolor DefaultBackgroundColor() const { return mBackgroundColor; }
+  nscolor DefaultLinkColor() const { return mLinkColor; }
+  nscolor DefaultActiveLinkColor() const { return mActiveLinkColor; }
+  nscolor DefaultVisitedLinkColor() const { return mVisitedLinkColor; }
+  nscolor FocusBackgroundColor() const { return mFocusBackgroundColor; }
+  nscolor FocusTextColor() const { return mFocusTextColor; }
+
+  /**
+   * Body text color, for use in quirks mode only.
+   */
+  nscolor BodyTextColor() const { return mBodyTextColor; }
+  void SetBodyTextColor(nscolor aColor) { mBodyTextColor = aColor; }
+
+  bool GetUseFocusColors() const { return mUseFocusColors; }
+  uint8_t FocusRingWidth() const { return mFocusRingWidth; }
+  bool GetFocusRingOnAnything() const { return mFocusRingOnAnything; }
+  uint8_t GetFocusRingStyle() const { return mFocusRingStyle; }
+
+  void SetContainer(nsIDocShell* aContainer);
+
+  virtual nsISupports* GetContainerWeakExternal() const;
+  nsISupports* GetContainerWeakInternal() const;
+#ifdef MOZILLA_INTERNAL_API
+  nsISupports* GetContainerWeak() const
+  { return GetContainerWeakInternal(); }
+#else
+  nsISupports* GetContainerWeak() const
+  { return GetContainerWeakExternal(); }
+#endif
+
+  nsIDocShell* GetDocShell() const;
+
+  // XXX this are going to be replaced with set/get container
+  void SetLinkHandler(nsILinkHandler* aHandler) { mLinkHandler = aHandler; }
+  nsILinkHandler* GetLinkHandler() { return mLinkHandler; }
+
+  /**
+   * Detach this pres context - i.e. cancel relevant timers,
+   * SetLinkHandler(null), SetContainer(null) etc.
+   * Only to be used by the DocumentViewer.
+   */
+  virtual void Detach();
+
+  /**
+   * Get the visible area associated with this presentation context.
+   * This is the size of the visible area that is used for
+   * presenting the document. The returned value is in the standard
+   * nscoord units (as scaled by the device context).
+   */
+  nsRect GetVisibleArea() const { return mVisibleArea; }
+
+  /**
+   * Set the currently visible area. The units for r are standard
+   * nscoord units (as scaled by the device context).
+   */
+  void SetVisibleArea(const nsRect& r) {
+    if (!r.IsEqualEdges(mVisibleArea)) {
+      mVisibleArea = r;
+      // Visible area does not affect media queries when paginated.
+      if (!IsPaginated() && HasCachedStyleData()) {
+        mPendingViewportChange = true;
+        PostMediaFeatureValuesChangedEvent();
+      }
+    }
+  }
+
+  /**
+   * Return true if this presentation context is a paginated
+   * context.
+   */
+  bool IsPaginated() const { return mPaginated; }
+
+  /**
+   * Sets whether the presentation context can scroll for a paginated
+   * context.
+   */
+  void SetPaginatedScrolling(bool aResult);
+
+  /**
+   * Return true if this presentation context can scroll for paginated
+   * context.
+   */
+  bool HasPaginatedScrolling() const { return mCanPaginatedScroll; }
+
+  /**
+   * Get/set the size of a page
+   */
+  nsSize GetPageSize() { return mPageSize; }
+  void SetPageSize(nsSize aSize) { mPageSize = aSize; }
+
+  /**
+   * Get/set whether this document should be treated as having real pages
+   * XXX This raises the obvious question of why a document that isn't a page
+   *     is paginated; there isn't a good reason except history
+   */
+  bool IsRootPaginatedDocument() { return mIsRootPaginatedDocument; }
+  void SetIsRootPaginatedDocument(bool aIsRootPaginatedDocument)
+    { mIsRootPaginatedDocument = aIsRootPaginatedDocument; }
+
+  /**
+  * Get/set the print scaling level; used by nsPageFrame to scale up
+  * pages.  Set safe to call before reflow, get guaranteed to be set
+  * properly after reflow.
+  */
+
+  float GetPageScale() { return mPageScale; }
+  void SetPageScale(float aScale) { mPageScale = aScale; }
+
+  /**
+  * Get/set the scaling facor to use when rendering the pages for print preview.
+  * Only safe to get after print preview set up; safe to set anytime.
+  * This is a scaling factor for the display of the print preview.  It
+  * does not affect layout.  It only affects the size of the onscreen pages
+  * in print preview.
+  * XXX Temporary: see http://wiki.mozilla.org/Gecko:PrintPreview
+  */
+  float GetPrintPreviewScale() { return mPPScale; }
+  void SetPrintPreviewScale(float aScale) { mPPScale = aScale; }
+
+  nsDeviceContext* DeviceContext() { return mDeviceContext; }
+  mozilla::EventStateManager* EventStateManager() { return mEventManager; }
+  nsIAtom* GetLanguageFromCharset() const { return mLanguage; }
+  already_AddRefed<nsIAtom> GetContentLanguage() const;
+
+  float TextZoom() { return mTextZoom; }
+  void SetTextZoom(float aZoom) {
+    MOZ_ASSERT(aZoom > 0.0f, "invalid zoom factor");
+    if (aZoom == mTextZoom)
+      return;
+
+    mTextZoom = aZoom;
+    if (HasCachedStyleData()) {
+      // Media queries could have changed, since we changed the meaning
+      // of 'em' units in them.
+      MediaFeatureValuesChanged(eRestyle_ForceDescendants,
+                                NS_STYLE_HINT_REFLOW);
+    }
+  }
+
+  /**
+   * Get the minimum font size for the specified language. If aLanguage
+   * is nullptr, then the document's language is used.  This combines
+   * the language-specific global preference with the per-presentation
+   * base minimum font size.
+   */
+  int32_t MinFontSize(nsIAtom *aLanguage) const {
+    const LangGroupFontPrefs *prefs = GetFontPrefsForLang(aLanguage);
+    return std::max(mBaseMinFontSize, prefs->mMinimumFontSize);
+  }
+
+  /**
+   * Get the per-presentation base minimum font size.  This size is
+   * independent of the language-specific global preference.
+   */
+  int32_t BaseMinFontSize() const {
+    return mBaseMinFontSize;
+  }
+
+  /**
+   * Set the per-presentation base minimum font size.  This size is
+   * independent of the language-specific global preference.
+   */
+  void SetBaseMinFontSize(int32_t aMinFontSize) {
+    if (aMinFontSize == mBaseMinFontSize)
+      return;
+
+    mBaseMinFontSize = aMinFontSize;
+    if (HasCachedStyleData()) {
+      // Media queries could have changed, since we changed the meaning
+      // of 'em' units in them.
+      MediaFeatureValuesChanged(eRestyle_ForceDescendants,
+                                NS_STYLE_HINT_REFLOW);
+    }
+  }
+
+  float GetFullZoom() { return mFullZoom; }
+  void SetFullZoom(float aZoom);
+
+  float GetOverrideDPPX() { return mOverrideDPPX; }
+  void SetOverrideDPPX(float aDPPX);
+
+  nscoord GetAutoQualityMinFontSize() {
+    return DevPixelsToAppUnits(mAutoQualityMinFontSizePixelsPref);
+  }
+
+  /**
+   * Return the device's screen size in inches, for font size
+   * inflation.
+   *
+   * If |aChanged| is non-null, then aChanged is filled in with whether
+   * the screen size value has changed since either:
+   *  a. the last time the function was called with non-null aChanged, or
+   *  b. the first time the function was called.
+   */
+  gfxSize ScreenSizeInchesForFontInflation(bool* aChanged = nullptr);
+
+  static int32_t AppUnitsPerCSSPixel() { return mozilla::AppUnitsPerCSSPixel(); }
+  int32_t AppUnitsPerDevPixel() const;
+  static int32_t AppUnitsPerCSSInch() { return mozilla::AppUnitsPerCSSInch(); }
+
+  static nscoord CSSPixelsToAppUnits(int32_t aPixels)
+  { return NSToCoordRoundWithClamp(float(aPixels) *
+             float(AppUnitsPerCSSPixel())); }
+
+  static nscoord CSSPixelsToAppUnits(float aPixels)
+  { return NSToCoordRoundWithClamp(aPixels *
+             float(AppUnitsPerCSSPixel())); }
+
+  static int32_t AppUnitsToIntCSSPixels(nscoord aAppUnits)
+  { return NSAppUnitsToIntPixels(aAppUnits,
+             float(AppUnitsPerCSSPixel())); }
+
+  static float AppUnitsToFloatCSSPixels(nscoord aAppUnits)
+  { return NSAppUnitsToFloatPixels(aAppUnits,
+             float(AppUnitsPerCSSPixel())); }
+
+  static double AppUnitsToDoubleCSSPixels(nscoord aAppUnits)
+  { return NSAppUnitsToDoublePixels(aAppUnits,
+             double(AppUnitsPerCSSPixel())); }
+
+  nscoord DevPixelsToAppUnits(int32_t aPixels) const
+  { return NSIntPixelsToAppUnits(aPixels, AppUnitsPerDevPixel()); }
+
+  int32_t AppUnitsToDevPixels(nscoord aAppUnits) const
+  { return NSAppUnitsToIntPixels(aAppUnits,
+             float(AppUnitsPerDevPixel())); }
+
+  float AppUnitsToFloatDevPixels(nscoord aAppUnits)
+  { return aAppUnits / float(AppUnitsPerDevPixel()); }
+
+  int32_t CSSPixelsToDevPixels(int32_t aPixels)
+  { return AppUnitsToDevPixels(CSSPixelsToAppUnits(aPixels)); }
+
+  float CSSPixelsToDevPixels(float aPixels)
+  {
+    return NSAppUnitsToFloatPixels(CSSPixelsToAppUnits(aPixels),
+                                   float(AppUnitsPerDevPixel()));
+  }
+
+  int32_t DevPixelsToIntCSSPixels(int32_t aPixels)
+  { return AppUnitsToIntCSSPixels(DevPixelsToAppUnits(aPixels)); }
+
+  float DevPixelsToFloatCSSPixels(int32_t aPixels)
+  { return AppUnitsToFloatCSSPixels(DevPixelsToAppUnits(aPixels)); }
+
+  mozilla::CSSToLayoutDeviceScale CSSToDevPixelScale() const
+  {
+    return mozilla::CSSToLayoutDeviceScale(
+        float(AppUnitsPerCSSPixel()) / float(AppUnitsPerDevPixel()));
+  }
+
+  // If there is a remainder, it is rounded to nearest app units.
+  nscoord GfxUnitsToAppUnits(gfxFloat aGfxUnits) const;
+
+  gfxFloat AppUnitsToGfxUnits(nscoord aAppUnits) const;
+
+  gfxRect AppUnitsToGfxUnits(const nsRect& aAppRect) const
+  { return gfxRect(AppUnitsToGfxUnits(aAppRect.x),
+                   AppUnitsToGfxUnits(aAppRect.y),
+                   AppUnitsToGfxUnits(aAppRect.width),
+                   AppUnitsToGfxUnits(aAppRect.height)); }
+
+  static nscoord CSSTwipsToAppUnits(float aTwips)
+  { return NSToCoordRoundWithClamp(
+      mozilla::AppUnitsPerCSSInch() * NS_TWIPS_TO_INCHES(aTwips)); }
+
+  // Margin-specific version, since they often need TwipsToAppUnits
+  static nsMargin CSSTwipsToAppUnits(const nsIntMargin &marginInTwips)
+  { return nsMargin(CSSTwipsToAppUnits(float(marginInTwips.top)),
+                    CSSTwipsToAppUnits(float(marginInTwips.right)),
+                    CSSTwipsToAppUnits(float(marginInTwips.bottom)),
+                    CSSTwipsToAppUnits(float(marginInTwips.left))); }
+
+  static nscoord CSSPointsToAppUnits(float aPoints)
+  { return NSToCoordRound(aPoints * mozilla::AppUnitsPerCSSInch() /
+                          POINTS_PER_INCH_FLOAT); }
+
+  nscoord RoundAppUnitsToNearestDevPixels(nscoord aAppUnits) const
+  { return DevPixelsToAppUnits(AppUnitsToDevPixels(aAppUnits)); }
+
+  /**
+   * This checks the root element and the HTML BODY, if any, for an "overflow"
+   * property that should be applied to the viewport. If one is found then we
+   * return the element that we took the overflow from (which should then be
+   * treated as "overflow: visible"), and we store the overflow style here.
+   * If the document is in fullscreen, and the fullscreen element is not the
+   * root, the scrollbar of viewport will be suppressed.
+   * @return if scroll was propagated from some content node, the content node
+   *         it was propagated from.
+   */
+  nsIContent* UpdateViewportScrollbarStylesOverride();
+  const ScrollbarStyles& GetViewportScrollbarStylesOverride()
+  {
+    return mViewportStyleScrollbar;
+  }
+
+  /**
+   * Check whether the given element would propagate its scrollbar styles to the
+   * viewport in non-paginated mode.  Must only be called if IsPaginated().
+   */
+  bool ElementWouldPropagateScrollbarStyles(mozilla::dom::Element* aElement);
+
+  /**
+   * Set and get methods for controlling the background drawing
+  */
+  bool GetBackgroundImageDraw() const { return mDrawImageBackground; }
+  void   SetBackgroundImageDraw(bool aCanDraw)
+  {
+    mDrawImageBackground = aCanDraw;
+  }
+
+  bool GetBackgroundColorDraw() const { return mDrawColorBackground; }
+  void   SetBackgroundColorDraw(bool aCanDraw)
+  {
+    mDrawColorBackground = aCanDraw;
+  }
+
+  /**
+   *  Check if bidi enabled (set depending on the presence of RTL
+   *  characters or when default directionality is RTL).
+   *  If enabled, we should apply the Unicode Bidi Algorithm
+   *
+   *  @lina 07/12/2000
+   */
+#ifdef MOZILLA_INTERNAL_API
+  bool BidiEnabled() const { return BidiEnabledInternal(); }
+#else
+  bool BidiEnabled() const { return BidiEnabledExternal(); }
+#endif
+  virtual bool BidiEnabledExternal() const;
+  bool BidiEnabledInternal() const;
+
+  /**
+   *  Set bidi enabled. This means we should apply the Unicode Bidi Algorithm
+   *
+   *  @lina 07/12/2000
+   */
+  void SetBidiEnabled() const;
+
+  /**
+   *  Set visual or implicit mode into the pres context.
+   *
+   *  Visual directionality is a presentation method that displays text
+   *  as if it were a uni-directional, according to the primary display
+   *  direction only.
+   *
+   *  Implicit directionality is a presentation method in which the
+   *  direction is determined by the Bidi algorithm according to the
+   *  category of the characters and the category of the adjacent
+   *  characters, and according to their primary direction.
+   *
+   *  @lina 05/02/2000
+   */
+  void SetVisualMode(bool aIsVisual)
+  {
+    mIsVisual = aIsVisual;
+  }
+
+  /**
+   *  Check whether the content should be treated as visual.
+   *
+   *  @lina 05/02/2000
+   */
+  bool IsVisualMode() const { return mIsVisual; }
+
+//Mohamed
+
+  /**
+   * Set the Bidi options for the presentation context
+   */
+  void SetBidi(uint32_t aBidiOptions,
+                           bool aForceRestyle = false);
+
+  /**
+   * Get the Bidi options for the presentation context
+   * Not inline so consumers of nsPresContext are not forced to
+   * include nsIDocument.
+   */
+  uint32_t GetBidi() const;
+
+  /**
+   * Render only Selection
+   */
+  void SetIsRenderingOnlySelection(bool aResult)
+  {
+    mIsRenderingOnlySelection = aResult;
+  }
+
+  bool IsRenderingOnlySelection() const { return mIsRenderingOnlySelection; }
+
+  bool IsTopLevelWindowInactive();
+
+  /*
+   * Obtain a native them for rendering our widgets (both form controls and html)
+   */
+  nsITheme* GetTheme();
+
+  /*
+   * Notify the pres context that the theme has changed.  An internal switch
+   * means it's one of our Mozilla themes that changed (e.g., Modern to Classic).
+   * Otherwise, the OS is telling us that the native theme for the platform
+   * has changed.
+   */
+  void ThemeChanged();
+
+  /*
+   * Notify the pres context that the resolution of the user interface has
+   * changed. This happens if a window is moved between HiDPI and non-HiDPI
+   * displays, so that the ratio of points to device pixels changes.
+   * The notification happens asynchronously.
+   */
+  void UIResolutionChanged();
+
+ /*
+  * Like UIResolutionChanged() but invalidates values immediately.
+  */
+  void UIResolutionChangedSync();
+
+  /*
+   * Notify the pres context that a system color has changed
+   */
+  void SysColorChanged();
+
+  /** Printing methods below should only be used for Medium() == print **/
+  void SetPrintSettings(nsIPrintSettings *aPrintSettings);
+
+  nsIPrintSettings* GetPrintSettings() { return mPrintSettings; }
+
+  /* Accessor for table of frame properties */
+  FramePropertyTable* PropertyTable() { return &mPropertyTable; }
+
+  /* Helper function that ensures that this prescontext is shown in its
+     docshell if it's the most recent prescontext for the docshell.  Returns
+     whether the prescontext is now being shown.
+  */
+  bool EnsureVisible();
+
+#ifdef MOZ_REFLOW_PERF
+  void CountReflows(const char * aName,
+                                nsIFrame * aFrame);
+#endif
+
+  void RestyledElement() {
+    ++mElementsRestyled;
+  }
+  void ConstructedFrame() {
+    ++mFramesConstructed;
+  }
+  void ReflowedFrame() {
+    ++mFramesReflowed;
+  }
+
+  uint64_t ElementsRestyledCount() {
+    return mElementsRestyled;
+  }
+  uint64_t FramesConstructedCount() {
+    return mFramesConstructed;
+  }
+  uint64_t FramesReflowedCount() {
+    return mFramesReflowed;
+  }
+
+  /**
+   * This table maps border-width enums 'thin', 'medium', 'thick'
+   * to actual nscoord values.
+   */
+  const nscoord* GetBorderWidthTable() { return mBorderWidthTable; }
+
+  gfxTextPerfMetrics *GetTextPerfMetrics() { return mTextPerf; }
+
+  bool IsDynamic() { return (mType == eContext_PageLayout || mType == eContext_Galley); }
+  bool IsScreen() { return (mMedium == nsGkAtoms::screen ||
+                              mType == eContext_PageLayout ||
+                              mType == eContext_PrintPreview); }
+
+  // Is this presentation in a chrome docshell?
+  bool IsChrome() const { return mIsChrome; }
+  bool IsChromeOriginImage() const { return mIsChromeOriginImage; }
+  void UpdateIsChrome();
+
+  // Public API for native theme code to get style internals.
+  bool HasAuthorSpecifiedRules(const nsIFrame *aFrame,
+                               uint32_t ruleTypeMask) const;
+
+  // Is it OK to let the page specify colors and backgrounds?
+  bool UseDocumentColors() const {
+    MOZ_ASSERT(mUseDocumentColors || !(IsChrome() || IsChromeOriginImage()),
+               "We should never have a chrome doc or image that can't use its colors.");
+    return mUseDocumentColors;
+  }
+
+  // Explicitly enable and disable paint flashing.
+  void SetPaintFlashing(bool aPaintFlashing) {
+    mPaintFlashing = aPaintFlashing;
+    mPaintFlashingInitialized = true;
+  }
+
+  // This method should be used instead of directly accessing mPaintFlashing,
+  // as that value may be out of date when mPaintFlashingInitialized is false.
+  bool GetPaintFlashing() const;
+
+  bool             SuppressingResizeReflow() const { return mSuppressResizeReflow; }
+
+  gfxUserFontSet* GetUserFontSet(bool aFlushUserFontSet = true);
+
+  // Should be called whenever the set of fonts available in the user
+  // font set changes (e.g., because a new font loads, or because the
+  // user font set is changed and fonts become unavailable).
+  void UserFontSetUpdated(gfxUserFontEntry* aUpdatedFont = nullptr);
+
+  gfxMissingFontRecorder *MissingFontRecorder() { return mMissingFonts; }
+  void NotifyMissingFonts();
+
+  void FlushCounterStyles();
+  void RebuildCounterStyles(); // asynchronously
+
+  // Ensure that it is safe to hand out CSS rules outside the layout
+  // engine by ensuring that all CSS style sheets have unique inners
+  // and, if necessary, synchronously rebuilding all style data.
+  void EnsureSafeToHandOutCSSRules();
+
+  void NotifyInvalidation(uint32_t aFlags);
+  void NotifyInvalidation(const nsRect& aRect, uint32_t aFlags);
+  // aRect is in device pixels
+  void NotifyInvalidation(const nsIntRect& aRect, uint32_t aFlags);
+  // aFlags are nsIPresShell::PAINT_ flags
+  void NotifyDidPaintForSubtree(uint32_t aFlags, uint64_t aTransactionId = 0,
+                                const mozilla::TimeStamp& aTimeStamp = mozilla::TimeStamp());
+  void FireDOMPaintEvent(nsInvalidateRequestList* aList, uint64_t aTransactionId);
+
+  // Callback for catching invalidations in ContainerLayers
+  // Passed to LayerProperties::ComputeDifference
+  static void NotifySubDocInvalidation(mozilla::layers::ContainerLayer* aContainer,
+                                       const nsIntRegion& aRegion);
+  void SetNotifySubDocInvalidationData(mozilla::layers::ContainerLayer* aContainer);
+  static void ClearNotifySubDocInvalidationData(mozilla::layers::ContainerLayer* aContainer);
+  bool IsDOMPaintEventPending();
+  void ClearMozAfterPaintEvents() {
+    mInvalidateRequestsSinceLastPaint.mRequests.Clear();
+    mUndeliveredInvalidateRequestsBeforeLastPaint.mRequests.Clear();
+    mAllInvalidated = false;
+  }
+
+  /**
+   * Returns the RestyleManager's restyle generation counter.
+   */
+  uint64_t GetRestyleGeneration() const;
+
+  /**
+   * Returns whether there are any pending restyles or reflows.
+   */
+  bool HasPendingRestyleOrReflow();
+
+  /**
+   * Informs the document's FontFaceSet that the refresh driver ticked,
+   * flushing style and layout.
+   */
+  void NotifyFontFaceSetOnRefresh();
+
+  /**
+   * Notify the prescontext that the presshell is about to reflow a reflow root.
+   * The single argument indicates whether this reflow should be interruptible.
+   * If aInterruptible is false then CheckForInterrupt and HasPendingInterrupt
+   * will always return false. If aInterruptible is true then CheckForInterrupt
+   * will return true when a pending event is detected.  This is for use by the
+   * presshell only.  Reflow code wanting to prevent interrupts should use
+   * InterruptPreventer.
+   */
+  void ReflowStarted(bool aInterruptible);
+
+  /**
+   * A class that can be used to temporarily disable reflow interruption.
+   */
+  class InterruptPreventer;
+  friend class InterruptPreventer;
+  class MOZ_STACK_CLASS InterruptPreventer {
+  public:
+    explicit InterruptPreventer(nsPresContext* aCtx) :
+      mCtx(aCtx),
+      mInterruptsEnabled(aCtx->mInterruptsEnabled),
+      mHasPendingInterrupt(aCtx->mHasPendingInterrupt)
+    {
+      mCtx->mInterruptsEnabled = false;
+      mCtx->mHasPendingInterrupt = false;
+    }
+    ~InterruptPreventer() {
+      mCtx->mInterruptsEnabled = mInterruptsEnabled;
+      mCtx->mHasPendingInterrupt = mHasPendingInterrupt;
+    }
+
+  private:
+    nsPresContext* mCtx;
+    bool mInterruptsEnabled;
+    bool mHasPendingInterrupt;
+  };
+
+  /**
+   * Check for interrupts. This may return true if a pending event is
+   * detected. Once it has returned true, it will keep returning true
+   * until ReflowStarted is called. In all cases where this returns true,
+   * the passed-in frame (which should be the frame whose reflow will be
+   * interrupted if true is returned) will be passed to
+   * nsIPresShell::FrameNeedsToContinueReflow.
+   */
+  bool CheckForInterrupt(nsIFrame* aFrame);
+  /**
+   * Returns true if CheckForInterrupt has returned true since the last
+   * ReflowStarted call. Cannot itself trigger an interrupt check.
+   */
+  bool HasPendingInterrupt() { return mHasPendingInterrupt; }
+  /**
+   * Sets a flag that will trip a reflow interrupt. This only bypasses the
+   * interrupt timeout and the pending event check; other checks such as whether
+   * interrupts are enabled and the interrupt check skipping still take effect.
+   */
+  void SetPendingInterruptFromTest() { mPendingInterruptFromTest = true; }
+
+  /**
+   * If we have a presshell, and if the given content's current
+   * document is the same as our presshell's document, return the
+   * content's primary frame.  Otherwise, return null.  Only use this
+   * if you care about which presshell the primary frame is in.
+   */
+  nsIFrame* GetPrimaryFrameFor(nsIContent* aContent);
+
+  void NotifyDestroyingFrame(nsIFrame* aFrame)
+  {
+    PropertyTable()->DeleteAllFor(aFrame);
+  }
+
+  virtual size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
+  virtual size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
+    return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
+  }
+
+  bool IsRootContentDocument() const;
+
+  bool HadNonBlankPaint() const {
+    return mHadNonBlankPaint;
+  }
+
+  void NotifyNonBlankPaint();
+
+  bool IsGlyph() const {
+    return mIsGlyph;
+  }
+
+  void SetIsGlyph(bool aValue) {
+    mIsGlyph = aValue;
+  }
+
+  bool UsesRootEMUnits() const {
+    return mUsesRootEMUnits;
+  }
+
+  void SetUsesRootEMUnits(bool aValue) {
+    mUsesRootEMUnits = aValue;
+  }
+
+  bool UsesExChUnits() const {
+    return mUsesExChUnits;
+  }
+
+  void SetUsesExChUnits(bool aValue) {
+    mUsesExChUnits = aValue;
+  }
+
+  bool UsesViewportUnits() const {
+    return mUsesViewportUnits;
+  }
+
+  void SetUsesViewportUnits(bool aValue) {
+    mUsesViewportUnits = aValue;
+  }
+
+  // true if there are OMTA transition updates for the current document which
+  // have been throttled, and therefore some style information may not be up
+  // to date
+  bool ExistThrottledUpdates() const {
+    return mExistThrottledUpdates;
+  }
+
+  void SetExistThrottledUpdates(bool aExistThrottledUpdates) {
+    mExistThrottledUpdates = aExistThrottledUpdates;
+  }
+
+  bool IsDeviceSizePageSize();
+
+  bool HasWarnedAboutPositionedTableParts() const {
+    return mHasWarnedAboutPositionedTableParts;
+  }
+
+  void SetHasWarnedAboutPositionedTableParts() {
+    mHasWarnedAboutPositionedTableParts = true;
+  }
+
+  bool HasWarnedAboutTooLargeDashedOrDottedRadius() const {
+    return mHasWarnedAboutTooLargeDashedOrDottedRadius;
+  }
+
+  void SetHasWarnedAboutTooLargeDashedOrDottedRadius() {
+    mHasWarnedAboutTooLargeDashedOrDottedRadius = true;
+  }
+
+protected:
+  friend class nsRunnableMethod<nsPresContext>;
+  void ThemeChangedInternal();
+  void SysColorChangedInternal();
+
+  // update device context's resolution from the widget
+  void UIResolutionChangedInternal();
+
+  // if aScale > 0.0, use it as resolution scale factor to the device context
+  // (otherwise get it from the widget)
+  void UIResolutionChangedInternalScale(double aScale);
+
+  // aData here is a pointer to a double that holds the CSS to device-pixel
+  // scale factor from the parent, which will be applied to the subdocument's
+  // device context instead of retrieving a scale from the widget.
+  static bool
+  UIResolutionChangedSubdocumentCallback(nsIDocument* aDocument, void* aData);
+
+  void SetImgAnimations(nsIContent *aParent, uint16_t aMode);
+  void SetSMILAnimations(nsIDocument *aDoc, uint16_t aNewMode,
+                                     uint16_t aOldMode);
+  void GetDocumentColorPreferences();
+
+  void PreferenceChanged(const char* aPrefName);
+  static void PrefChangedCallback(const char*, void*);
+
+  void UpdateAfterPreferencesChanged();
+  static void PrefChangedUpdateTimerCallback(nsITimer *aTimer, void *aClosure);
+
+  void GetUserPreferences();
+
+  /**
+   * Fetch the user's font preferences for the given aLanguage's
+   * langugage group.
+   */
+  const LangGroupFontPrefs* GetFontPrefsForLang(nsIAtom *aLanguage) const
+  {
+    nsIAtom* lang = aLanguage ? aLanguage : mLanguage.get();
+    return StaticPresData::Get()->GetFontPrefsForLangHelper(lang, &mLangGroupFontPrefs);
+  }
+
+  void UpdateCharSet(const nsCString& aCharSet);
+
+public:
+  void DoChangeCharSet(const nsCString& aCharSet);
+
+  /**
+   * Checks for MozAfterPaint listeners on the document
+   */
+  bool MayHavePaintEventListener();
+
+  /**
+   * Checks for MozAfterPaint listeners on the document and
+   * any subdocuments, except for subdocuments that are non-top-level
+   * content documents.
+   */
+  bool MayHavePaintEventListenerInSubDocument();
+
+#ifdef RESTYLE_LOGGING
+  // Controls for whether debug information about restyling in this
+  // document should be output.
+  bool RestyleLoggingEnabled() const { return mRestyleLoggingEnabled; }
+  void StartRestyleLogging() { mRestyleLoggingEnabled = true; }
+  void StopRestyleLogging() { mRestyleLoggingEnabled = false; }
+#endif
+
+  void InvalidatePaintedLayers();
+
+protected:
+  // May be called multiple times (unlink, destructor)
+  void Destroy();
+
+  void AppUnitsPerDevPixelChanged();
+
+  void HandleRebuildCounterStyles() {
+    mPostedFlushCounterStyles = false;
+    FlushCounterStyles();
+  }
+
+  bool HavePendingInputEvent();
+
+  // Can't be inline because we can't include nsStyleSet.h.
+  bool HasCachedStyleData();
+
+  // Creates a one-shot timer with the given aCallback & aDelay.
+  // Returns a refcounted pointer to the timer (or nullptr on failure).
+  already_AddRefed<nsITimer> CreateTimer(nsTimerCallbackFunc aCallback,
+                                         uint32_t aDelay);
+
+  // IMPORTANT: The ownership implicit in the following member variables
+  // has been explicitly checked.  If you add any members to this class,
+  // please make the ownership explicit (pinkerton, scc).
+
+  nsPresContextType     mType;
+  // the nsPresShell owns a strong reference to the nsPresContext, and is responsible
+  // for nulling this pointer before it is destroyed
+  nsIPresShell* MOZ_NON_OWNING_REF mShell;         // [WEAK]
+  nsCOMPtr<nsIDocument> mDocument;
+  RefPtr<nsDeviceContext> mDeviceContext; // [STRONG] could be weak, but
+                                            // better safe than sorry.
+                                            // Cannot reintroduce cycles
+                                            // since there is no dependency
+                                            // from gfx back to layout.
+  RefPtr<mozilla::EventStateManager> mEventManager;
+  RefPtr<nsRefreshDriver> mRefreshDriver;
+  RefPtr<mozilla::EffectCompositor> mEffectCompositor;
+  RefPtr<nsTransitionManager> mTransitionManager;
+  RefPtr<nsAnimationManager> mAnimationManager;
+  mozilla::RestyleManagerHandle::RefPtr mRestyleManager;
+  RefPtr<mozilla::CounterStyleManager> mCounterStyleManager;
+  nsIAtom* MOZ_UNSAFE_REF("always a static atom") mMedium; // initialized by subclass ctors
+  nsCOMPtr<nsIAtom> mMediaEmulated;
+
+  // This pointer is nulled out through SetLinkHandler() in the destructors of
+  // the classes which set it. (using SetLinkHandler() again).
+  nsILinkHandler* MOZ_NON_OWNING_REF mLinkHandler;
+
+  // Formerly mLangGroup; moving from charset-oriented langGroup to
+  // maintaining actual language settings everywhere (see bug 524107).
+  // This may in fact hold a langGroup such as x-western rather than
+  // a specific language, however (e.g, if it is inferred from the
+  // charset rather than explicitly specified as a lang attribute).
+  nsCOMPtr<nsIAtom>     mLanguage;
+
+public:
+  // The following are public member variables so that we can use them
+  // with mozilla::AutoToggle or mozilla::AutoRestore.
+
+  // Should we disable font size inflation because we're inside of
+  // shrink-wrapping calculations on an inflation container?
+  bool                  mInflationDisabledForShrinkWrap;
+
+protected:
+
+  mozilla::WeakPtr<nsDocShell>             mContainer;
+
+  // Base minimum font size, independent of the language-specific global preference. Defaults to 0
+  int32_t               mBaseMinFontSize;
+  float                 mTextZoom;      // Text zoom, defaults to 1.0
+  float                 mFullZoom;      // Page zoom, defaults to 1.0
+  float                 mOverrideDPPX;   // DPPX overrided, defaults to 0.0
+  gfxSize               mLastFontInflationScreenSize;
+
+  int32_t               mCurAppUnitsPerDevPixel;
+  int32_t               mAutoQualityMinFontSizePixelsPref;
+
+  nsCOMPtr<nsITheme> mTheme;
+  nsCOMPtr<nsILanguageAtomService> mLangService;
+  nsCOMPtr<nsIPrintSettings> mPrintSettings;
+  nsCOMPtr<nsITimer>    mPrefChangedTimer;
+
+  FramePropertyTable    mPropertyTable;
+
+  nsInvalidateRequestList mInvalidateRequestsSinceLastPaint;
+  nsInvalidateRequestList mUndeliveredInvalidateRequestsBeforeLastPaint;
+
+  // text performance metrics
+  nsAutoPtr<gfxTextPerfMetrics>   mTextPerf;
+
+  nsAutoPtr<gfxMissingFontRecorder> mMissingFonts;
+
+  nsRect                mVisibleArea;
+  nsSize                mPageSize;
+  float                 mPageScale;
+  float                 mPPScale;
+
+  nscolor               mDefaultColor;
+  nscolor               mBackgroundColor;
+
+  nscolor               mLinkColor;
+  nscolor               mActiveLinkColor;
+  nscolor               mVisitedLinkColor;
+
+  nscolor               mFocusBackgroundColor;
+  nscolor               mFocusTextColor;
+
+  nscolor               mBodyTextColor;
+
+  ScrollbarStyles       mViewportStyleScrollbar;
+  uint8_t               mFocusRingWidth;
+
+  bool mExistThrottledUpdates;
+
+  uint16_t              mImageAnimationMode;
+  uint16_t              mImageAnimationModePref;
+
+  // Most documents will only use one (or very few) language groups. Rather
+  // than have the overhead of a hash lookup, we simply look along what will
+  // typically be a very short (usually of length 1) linked list. There are 31
+  // language groups, so in the worst case scenario we'll need to traverse 31
+  // link items.
+  LangGroupFontPrefs    mLangGroupFontPrefs;
+
+  nscoord               mBorderWidthTable[3];
+
+  uint32_t              mInterruptChecksToSkip;
+
+  // Counters for tests and tools that want to detect frame construction
+  // or reflow.
+  uint64_t              mElementsRestyled;
+  uint64_t              mFramesConstructed;
+  uint64_t              mFramesReflowed;
+
+  mozilla::TimeStamp    mReflowStartTime;
+
+  // last time we did a full style flush
+  mozilla::TimeStamp    mLastStyleUpdateForAllAnimations;
+
+  unsigned              mHasPendingInterrupt : 1;
+  unsigned              mPendingInterruptFromTest : 1;
+  unsigned              mInterruptsEnabled : 1;
+  unsigned              mUseDocumentFonts : 1;
+  unsigned              mUseDocumentColors : 1;
+  unsigned              mUnderlineLinks : 1;
+  unsigned              mSendAfterPaintToContent : 1;
+  unsigned              mUseFocusColors : 1;
+  unsigned              mFocusRingOnAnything : 1;
+  unsigned              mFocusRingStyle : 1;
+  unsigned              mDrawImageBackground : 1;
+  unsigned              mDrawColorBackground : 1;
+  unsigned              mNeverAnimate : 1;
+  unsigned              mIsRenderingOnlySelection : 1;
+  unsigned              mPaginated : 1;
+  unsigned              mCanPaginatedScroll : 1;
+  unsigned              mDoScaledTwips : 1;
+  unsigned              mIsRootPaginatedDocument : 1;
+  unsigned              mPrefBidiDirection : 1;
+  unsigned              mPrefScrollbarSide : 2;
+  unsigned              mPendingSysColorChanged : 1;
+  unsigned              mPendingThemeChanged : 1;
+  unsigned              mPendingUIResolutionChanged : 1;
+  unsigned              mPendingMediaFeatureValuesChanged : 1;
+  unsigned              mPrefChangePendingNeedsReflow : 1;
+  unsigned              mIsEmulatingMedia : 1;
+  // True if the requests in mInvalidateRequestsSinceLastPaint cover the
+  // entire viewport
+  unsigned              mAllInvalidated : 1;
+
+  // Are we currently drawing an SVG glyph?
+  unsigned              mIsGlyph : 1;
+
+  // Does the associated document use root-em (rem) units?
+  unsigned              mUsesRootEMUnits : 1;
+  // Does the associated document use ex or ch units?
+  unsigned              mUsesExChUnits : 1;
+  // Does the associated document use viewport units (vw/vh/vmin/vmax)?
+  unsigned              mUsesViewportUnits : 1;
+
+  // Has there been a change to the viewport's dimensions?
+  unsigned              mPendingViewportChange : 1;
+
+  // Is the current mCounterStyleManager valid?
+  unsigned              mCounterStylesDirty : 1;
+  // Do we currently have an event posted to call FlushCounterStyles?
+  unsigned              mPostedFlushCounterStyles: 1;
+
+  // resize reflow is suppressed when the only change has been to zoom
+  // the document rather than to change the document's dimensions
+  unsigned              mSuppressResizeReflow : 1;
+
+  unsigned              mIsVisual : 1;
+
+  unsigned              mFireAfterPaintEvents : 1;
+
+  unsigned              mIsChrome : 1;
+  unsigned              mIsChromeOriginImage : 1;
+
+  // Should we paint flash in this context? Do not use this variable directly.
+  // Use GetPaintFlashing() method instead.
+  mutable unsigned mPaintFlashing : 1;
+  mutable unsigned mPaintFlashingInitialized : 1;
+
+  unsigned mHasWarnedAboutPositionedTableParts : 1;
+
+  unsigned mHasWarnedAboutTooLargeDashedOrDottedRadius : 1;
+
+  // Have we added quirk.css to the style set?
+  unsigned              mQuirkSheetAdded : 1;
+
+  // Is there a pref update to process once we have a container?
+  unsigned              mNeedsPrefUpdate : 1;
+
+  // Has NotifyNonBlankPaint been called on this PresContext?
+  unsigned              mHadNonBlankPaint : 1;
+
+#ifdef RESTYLE_LOGGING
+  // Should we output debug information about restyling for this document?
+  bool                  mRestyleLoggingEnabled;
+#endif
+
+#ifdef DEBUG
+  bool                  mInitialized;
+#endif
+
+
+protected:
+
+  virtual ~nsPresContext();
+
+  nscolor MakeColorPref(const nsString& aColor);
+
+  void LastRelease();
+
+#ifdef DEBUG
+private:
+  friend struct nsAutoLayoutPhase;
+  uint32_t mLayoutPhaseCount[eLayoutPhase_COUNT];
+public:
+  uint32_t LayoutPhaseCount(nsLayoutPhase aPhase) {
+    return mLayoutPhaseCount[aPhase];
+  }
+#endif
+
+};
+
+class nsRootPresContext final : public nsPresContext {
+public:
+  nsRootPresContext(nsIDocument* aDocument, nsPresContextType aType);
+  virtual ~nsRootPresContext();
+  virtual void Detach() override;
+
+  /**
+   * Ensure that NotifyDidPaintForSubtree is eventually called on this
+   * object after a timeout.
+   */
+  void EnsureEventualDidPaintEvent();
+
+  void CancelDidPaintTimer()
+  {
+    if (mNotifyDidPaintTimer) {
+      mNotifyDidPaintTimer->Cancel();
+      mNotifyDidPaintTimer = nullptr;
+    }
+  }
+
+  /**
+   * Registers a plugin to receive geometry updates (position and clip
+   * region) so it can update its widget.
+   * Callers must call UnregisterPluginForGeometryUpdates before
+   * the aPlugin frame is destroyed.
+   */
+  void RegisterPluginForGeometryUpdates(nsIContent* aPlugin);
+  /**
+   * Stops a plugin receiving geometry updates (position and clip
+   * region). If the plugin was not already registered, this does
+   * nothing.
+   */
+  void UnregisterPluginForGeometryUpdates(nsIContent* aPlugin);
+
+  bool NeedToComputePluginGeometryUpdates()
+  {
+    return mRegisteredPlugins.Count() > 0;
+  }
+  /**
+   * Compute geometry updates for each plugin given that aList is the display
+   * list for aFrame. The updates are not yet applied;
+   * ApplyPluginGeometryUpdates is responsible for that. In the meantime they
+   * are stored on each nsPluginFrame.
+   * This needs to be called even when aFrame is a popup, since although
+   * windowed plugins aren't allowed in popups, windowless plugins are
+   * and ComputePluginGeometryUpdates needs to be called for them.
+   */
+  void ComputePluginGeometryUpdates(nsIFrame* aFrame,
+                                    nsDisplayListBuilder* aBuilder,
+                                    nsDisplayList* aList);
+
+  /**
+   * Apply the stored plugin geometry updates. This should normally be called
+   * in DidPaint so the plugins are moved/clipped immediately after we've
+   * updated our window, so they look in sync with our window.
+   */
+  void ApplyPluginGeometryUpdates();
+
+  /**
+   * Transfer stored plugin geometry updates to the compositor. Called during
+   * reflow, data is shipped over with layer updates. e10s specific.
+   */
+  void CollectPluginGeometryUpdates(mozilla::layers::LayerManager* aLayerManager);
+
+  virtual bool IsRoot() override { return true; }
+
+  /**
+   * Increment DOM-modification generation counter to indicate that
+   * the DOM has changed in a way that might lead to style changes/
+   * reflows/frame creation and destruction.
+   */
+  void IncrementDOMGeneration() { mDOMGeneration++; }
+
+  /**
+   * Get the current DOM generation counter.
+   *
+   * See nsFrameManagerBase::GetGlobalGenerationNumber() for a
+   * global generation number.
+   */
+  uint32_t GetDOMGeneration() { return mDOMGeneration; }
+
+  /**
+   * Add a runnable that will get called before the next paint. They will get
+   * run eventually even if painting doesn't happen. They might run well before
+   * painting happens.
+   */
+  void AddWillPaintObserver(nsIRunnable* aRunnable);
+
+  /**
+   * Run all runnables that need to get called before the next paint.
+   */
+  void FlushWillPaintObservers();
+
+  virtual size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const override;
+
+protected:
+  /**
+   * Start a timer to ensure we eventually run ApplyPluginGeometryUpdates.
+   */
+  void InitApplyPluginGeometryTimer();
+  /**
+   * Cancel the timer that ensures we eventually run ApplyPluginGeometryUpdates.
+   */
+  void CancelApplyPluginGeometryTimer();
+
+  class RunWillPaintObservers : public mozilla::Runnable {
+  public:
+    explicit RunWillPaintObservers(nsRootPresContext* aPresContext) : mPresContext(aPresContext) {}
+    void Revoke() { mPresContext = nullptr; }
+    NS_IMETHOD Run() override
+    {
+      if (mPresContext) {
+        mPresContext->FlushWillPaintObservers();
+      }
+      return NS_OK;
+    }
+    // The lifetime of this reference is handled by an nsRevocableEventPtr
+    nsRootPresContext* MOZ_NON_OWNING_REF mPresContext;
+  };
+
+  friend class nsPresContext;
+
+  nsCOMPtr<nsITimer> mNotifyDidPaintTimer;
+  nsCOMPtr<nsITimer> mApplyPluginGeometryTimer;
+  nsTHashtable<nsRefPtrHashKey<nsIContent> > mRegisteredPlugins;
+  nsTArray<nsCOMPtr<nsIRunnable> > mWillPaintObservers;
+  nsRevocableEventPtr<RunWillPaintObservers> mWillPaintFallbackEvent;
+  uint32_t mDOMGeneration;
+};
+
+#ifdef MOZ_REFLOW_PERF
+
+#define DO_GLOBAL_REFLOW_COUNT(_name) \
+  aPresContext->CountReflows((_name), (nsIFrame*)this);
+#else
+#define DO_GLOBAL_REFLOW_COUNT(_name)
+#endif // MOZ_REFLOW_PERF
+
+#endif /* nsPresContext_h___ */