Make OffscreenCanvas animation in sync with its placeholder canvas's parent frame rate

content/browser/renderer_host/offscreen_canvas_surface_manager.h

Index: content/browser/renderer_host/offscreen_canvas_surface_manager.h
diff --git a/content/browser/renderer_host/offscreen_canvas_surface_manager.h b/content/browser/renderer_host/offscreen_canvas_surface_manager.h
index e53cea7037c5e09512523121927d78c2c467f543..f052507ea042aff86127196869a73447b4876682 100644
--- a/content/browser/renderer_host/offscreen_canvas_surface_manager.h
+++ b/content/browser/renderer_host/offscreen_canvas_surface_manager.h
@@ -20,10 +20,16 @@ class CONTENT_EXPORT OffscreenCanvasSurfaceManager
 
   static OffscreenCanvasSurfaceManager* GetInstance();
 
-  void RegisterOffscreenCanvasSurfaceInstance(cc::FrameSinkId,
+  // Registration of the frame sink with the given frame sink id to its parent
+  // frame sink (if it has one), so that parent frame is able to send signals
+  // to it on begin frame.
+  void RegisterFrameSinkToParent(const cc::FrameSinkId&);

[Fady Samuel, 2017/01/19 17:10:54]

chromium style nit: give the param a name:

e.g. const cc::FrameSinkId& frame_sink_id

[xlai (Olivia), 2017/01/19 19:14:34]

Done for here and elsewhere.

+  void UnregisterFrameSinkFromParent(const cc::FrameSinkId&);

[Fady Samuel, 2017/01/19 17:10:53]

chromium style nit: give the param a name:

e.g. const cc::FrameSinkId& frame_sink_id

+
+  void RegisterOffscreenCanvasSurfaceInstance(const cc::FrameSinkId&,

[Fady Samuel, 2017/01/19 17:10:54]

chromium style nit: give the param a name:

e.g. const cc::FrameSinkId& frame_sink_id

                                               OffscreenCanvasSurfaceImpl*);

[Fady Samuel, 2017/01/19 17:10:54]

chromium style nit: give the param a name:

e.g OffscreencanvasSurfaceImpl* offscreen_canvas_surface

-  void UnregisterOffscreenCanvasSurfaceInstance(cc::FrameSinkId);
-  OffscreenCanvasSurfaceImpl* GetSurfaceInstance(cc::FrameSinkId);
+  void UnregisterOffscreenCanvasSurfaceInstance(const cc::FrameSinkId&);

[Fady Samuel, 2017/01/19 17:10:54]

const cc::FrameSinkId& frame_sink_id

+  OffscreenCanvasSurfaceImpl* GetSurfaceInstance(const cc::FrameSinkId&);

[Fady Samuel, 2017/01/19 17:10:53]

const cc::FrameSinkId& frame_sink_id

 
  private:
   friend class OffscreenCanvasSurfaceManagerTest;