Issue #953 - Neuter the user-facing controls for e10s

This should prevent people using a massive footgun that would blow off
their entire legs. Requires appropriate FE changes.

3 files changed, 7 insertions, 45 deletions

diff --git a/gfx/config/gfxVars.h b/gfx/config/gfxVars.h
index fd4864dd56..6ac8c21326 100644
--- a/gfx/config/gfxVars.h
+++ b/gfx/config/gfxVars.h
@@ -22,7 +22,6 @@ class gfxVarReceiver;
 // Generator for graphics vars.
 #define GFX_VARS_LIST(_)                                                \
   /* C++ Name,                  Data Type,        Default Value */      \
-  _(BrowserTabsRemoteAutostart, bool,             false)                \
   _(ContentBackend,             BackendType,      BackendType::NONE)    \
   _(TileSize,                   IntSize,          IntSize(-1, -1))      \
   _(UseXRender,                 bool,             false)                \
diff --git a/gfx/layers/ipc/CompositorBridgeParent.cpp b/gfx/layers/ipc/CompositorBridgeParent.cpp
index e650b2dcf1..d08176b6a5 100644
--- a/gfx/layers/ipc/CompositorBridgeParent.cpp
+++ b/gfx/layers/ipc/CompositorBridgeParent.cpp
@@ -1183,16 +1183,6 @@ CompositorBridgeParent::CompositeToTarget(DrawTarget* aTarget, const gfx::IntRec
                                &hasRemoteContent,
                                &updatePluginsFlag);
 
-#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
-  // We do not support plugins in local content. When switching tabs
-  // to local pages, hide every plugin associated with the window.
-  if (!hasRemoteContent && gfxVars::BrowserTabsRemoteAutostart() &&
-      mCachedPluginData.Length()) {
-    Unused << SendHideAllPlugins(GetWidget()->GetWidgetKey());
-    mCachedPluginData.Clear();
-  }
-#endif
-
   if (aTarget) {
     mLayerManager->BeginTransactionWithDrawTarget(aTarget, *aRect);
   } else {
diff --git a/gfx/thebes/gfxPlatform.cpp b/gfx/thebes/gfxPlatform.cpp
index 28282a90d2..21e15bf06f 100644
--- a/gfx/thebes/gfxPlatform.cpp
+++ b/gfx/thebes/gfxPlatform.cpp
@@ -519,12 +519,7 @@ static uint32_t GetSkiaGlyphCacheSize()
     // Chromium uses 20mb and skia default uses 2mb.
     // We don't need to change the font cache count since we usually
     // cache thrash due to asian character sets in talos.
-    // Only increase memory on the content proces
     uint32_t cacheSize = 10 * 1024 * 1024;
-    if (mozilla::BrowserTabsRemoteAutostart()) {
-      return XRE_IsContentProcess() ? cacheSize : kDefaultGlyphCacheSize;
-    }
-
     return cacheSize;
 }
 #endif
@@ -2023,7 +2018,6 @@ gfxPlatform::InitAcceleration()
   gfxPrefs::GetSingleton();
 
   if (XRE_IsParentProcess()) {
-    gfxVars::SetBrowserTabsRemoteAutostart(BrowserTabsRemoteAutostart());
     gfxVars::SetOffscreenFormat(GetOffscreenFormat());
     gfxVars::SetRequiresAcceleratedGLContextForCompositorOGL(
               RequiresAcceleratedGLContextForCompositorOGL());
@@ -2075,30 +2069,11 @@ gfxPlatform::InitGPUProcessPrefs()
     gpuProc.UserForceEnable("User force-enabled via pref");
   }
 
-  // We require E10S - otherwise, there is very little benefit to the GPU
-  // process, since the UI process must still use acceleration for
-  // performance.
-  if (!BrowserTabsRemoteAutostart()) {
-    gpuProc.ForceDisable(
-      FeatureStatus::Unavailable,
-      "Multi-process mode is not enabled",
-      NS_LITERAL_CSTRING("FEATURE_FAILURE_NO_E10S"));
-    return;
-  }
-  if (InSafeMode()) {
-    gpuProc.ForceDisable(
-      FeatureStatus::Blocked,
-      "Safe-mode is enabled",
-      NS_LITERAL_CSTRING("FEATURE_FAILURE_SAFE_MODE"));
-    return;
-  }
-  if (gfxPrefs::LayerScopeEnabled()) {
-    gpuProc.ForceDisable(
-      FeatureStatus::Blocked,
-      "LayerScope does not work in the GPU process",
-      NS_LITERAL_CSTRING("FEATURE_FAILURE_LAYERSCOPE"));
-    return;
-  }
+  gpuProc.ForceDisable(
+    FeatureStatus::Unavailable,
+    "GPU processes are not supported",
+    NS_LITERAL_CSTRING("FEATURE_FAILURE_NO_E10S"));
+  return;
 }
 
 void
@@ -2203,9 +2178,7 @@ gfxPlatform::UsesOffMainThreadCompositing()
 
   if (firstTime) {
     MOZ_ASSERT(sLayersAccelerationPrefsInitialized);
-    result =
-      gfxVars::BrowserTabsRemoteAutostart() ||
-      !gfxPrefs::LayersOffMainThreadCompositionForceDisabled();
+    result = !gfxPrefs::LayersOffMainThreadCompositionForceDisabled();
 #if defined(MOZ_WIDGET_GTK)
     // Linux users who chose OpenGL are being grandfathered in to OMTC
     result |= gfxPrefs::LayersAccelerationForceEnabledDoNotUseDirectly();
@@ -2302,7 +2275,7 @@ gfxPlatform::AsyncPanZoomEnabled()
 #if !defined(MOZ_WIDGET_UIKIT)
   // For XUL applications (everything but Firefox on Android) we only want
   // to use APZ when E10S is enabled or when the user explicitly enable it.
-  if (BrowserTabsRemoteAutostart() || gfxPrefs::APZDesktopEnabled()) {
+  if (gfxPrefs::APZDesktopEnabled()) {
     return gfxPrefs::AsyncPanZoomEnabledDoNotUseDirectly();
   } else {
     return false;