Move CanvasRenderingContext2D timer to frame-specific TaskRunnerTimer.

third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.h

 /*
  * Copyright (C) 2006, 2007, 2009, 2010, 2011, 2012 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
@@ skipping 233 matching lines @@
   DECLARE_VIRTUAL_TRACE();
 
   virtual bool isTransformInvertible() const;
 
   WebLayer* platformLayer() const override;
 
   Member<HitRegionManager> m_hitRegionManager;
   LostContextMode m_contextLostMode;
   bool m_contextRestorable;
   unsigned m_tryRestoreContextAttemptCount;
-  Timer<CanvasRenderingContext2D> m_dispatchContextLostEventTimer;
-  Timer<CanvasRenderingContext2D> m_dispatchContextRestoredEventTimer;
-  Timer<CanvasRenderingContext2D> m_tryRestoreContextEventTimer;
+  TaskRunnerTimer<CanvasRenderingContext2D> m_dispatchContextLostEventTimer;
+  TaskRunnerTimer<CanvasRenderingContext2D> m_dispatchContextRestoredEventTimer;
+  TaskRunnerTimer<CanvasRenderingContext2D> m_tryRestoreContextEventTimer;
 
   FilterOperations m_filterOperations;
   HashMap<String, Font> m_fontsResolvedUsingCurrentStyle;
   bool m_pruneLocalFontCacheScheduled;
   ListHashSet<String> m_fontLRUList;
 };
 
 DEFINE_TYPE_CASTS(CanvasRenderingContext2D,
                   CanvasRenderingContext,
                   context,
                   context->is2d() && context->canvas(),
                   context.is2d() && context.canvas());
 
 }  // namespace blink
 
 #endif  // CanvasRenderingContext2D_h