Simplify rate limiter logic in Canvas2DLayerBridge

third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h

Index: third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
diff --git a/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h b/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
index d1a7f13c9543e5fcd40c7d0c8799d237f01a029b..af91f3543ffc84a20e2d112266df0f88bb677ffc 100644
--- a/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
+++ b/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
@@ -34,7 +34,6 @@
 #include "platform/graphics/paint/PaintRecorder.h"
 #include "platform/graphics/paint/PaintSurface.h"
 #include "public/platform/WebExternalTextureLayer.h"
-#include "public/platform/WebThread.h"
 #include "third_party/khronos/GLES2/gl2.h"
 #include "third_party/skia/include/core/SkRefCnt.h"
 #include "ui/gfx/color_space.h"
@@ -80,7 +79,6 @@ class SharedContextRateLimiter;
 
 class PLATFORM_EXPORT Canvas2DLayerBridge
     : public NON_EXPORTED_BASE(cc::TextureLayerClient),
-      public WebThread::TaskObserver,
       public RefCounted<Canvas2DLayerBridge> {
   WTF_MAKE_NONCOPYABLE(Canvas2DLayerBridge);
 
@@ -205,13 +203,8 @@ class PLATFORM_EXPORT Canvas2DLayerBridge
   void startRecording();
   void skipQueuedDrawCommands();
   void flushRecordingOnly();
-  void unregisterTaskObserver();
   void reportSurfaceCreationFailure();
 
-  // WebThread::TaskOberver implementation
-  void willProcessTask() override;
-  void didProcessTask() override;
-
   PaintSurface* getOrCreateSurface(AccelerationHint = PreferAcceleration);
   bool shouldAccelerate(AccelerationHint) const;
 
@@ -265,8 +258,7 @@ class PLATFORM_EXPORT Canvas2DLayerBridge
   SkFilterQuality m_filterQuality;
   bool m_isHidden;
   bool m_isDeferralEnabled;
-  bool m_isRegisteredTaskObserver;
-  bool m_renderingTaskCompletedForCurrentFrame;
+  bool m_previousFrameWasPresented;
   bool m_softwareRenderingWhileHidden;
   bool m_surfaceCreationFailedAtLeastOnce = false;
   bool m_hibernationScheduled = false;