Backed out changeset 61465f67b591 (bug 1167235)

dom/canvas/CanvasRenderingContext2D.cpp

@@ -42,7 +42,6 @@
 #include "nsPIDOMWindow.h"
 #include "nsDisplayList.h"
 #include "nsFocusManager.h"
-#include "nsContentUtils.h"
 
 #include "nsTArray.h"
 
@@ -1066,7 +1065,6 @@ CanvasRenderingContext2D::CanvasRenderingContext2D()
   , mResetLayer(true)
   , mIPC(false)
   , mIsSkiaGL(false)
-  , mHasPendingStableStateCallback(false)
   , mDrawObserver(nullptr)
   , mIsEntireFrameInvalid(false)
   , mPredictManyRedrawCalls(false)
@@ -1511,27 +1509,6 @@ CanvasRenderingContext2D::CheckSizeForSkiaGL(IntSize aSize) {
   return threshold < 0 || (aSize.width * aSize.height) <= threshold;
 }
 
-void
-CanvasRenderingContext2D::ScheduleStableStateCallback()
-{
-  if (mHasPendingStableStateCallback) {
-    return;
-  }
-  mHasPendingStableStateCallback = true;
-
-  nsContentUtils::RunInStableState(
-    NewRunnableMethod(this, &CanvasRenderingContext2D::OnStableState)
-  );
-}
-
-void
-CanvasRenderingContext2D::OnStableState()
-{
-  ReturnTarget();
-
-  mHasPendingStableStateCallback = false;
-}
-
 CanvasRenderingContext2D::RenderingMode
 CanvasRenderingContext2D::EnsureTarget(const gfx::Rect* aCoveredRect,
                                        RenderingMode aRenderingMode)
@@ -1560,8 +1537,6 @@ CanvasRenderingContext2D::EnsureTarget(const gfx::Rect* aCoveredRect,
       mTarget = mBufferProvider->BorrowDrawTarget(IntRect(0, 0, mWidth, mHeight));
     }
 
-    ScheduleStableStateCallback();
-
     if (mTarget) {
       // Restore clip and transform.
       mTarget->SetTransform(CurrentState().transform);

dom/canvas/CanvasRenderingContext2D.h

@@ -640,19 +640,6 @@ protected:
   RenderingMode EnsureTarget(const gfx::Rect* aCoveredRect = nullptr,
                              RenderingMode aRenderMode = RenderingMode::DefaultBackendMode);
 
-  /**
-   * This method is run at the end of the event-loop spin where
-   * ScheduleStableStateCallback was called.
-   *
-   * We use it to unlock resources that need to be locked while drawing.
-   */
-  void OnStableState();
-
-  /**
-   * Cf. OnStableState.
-   */
-  void ScheduleStableStateCallback();
-
   /**
    * Disposes an old target and prepares to lazily create a new target.
    */
@@ -744,8 +731,6 @@ protected:
   // requesting the DT from mBufferProvider to check.
   bool mIsSkiaGL;
 
-  bool mHasPendingStableStateCallback;
-
   nsTArray<CanvasRenderingContext2DUserData*> mUserDatas;
 
   // If mCanvasElement is not provided, then a docshell is