Hide compositor_frame_sink_id from RenderWidgetHostView*

content/browser/renderer_host/render_widget_host_impl.h

Index: content/browser/renderer_host/render_widget_host_impl.h
diff --git a/content/browser/renderer_host/render_widget_host_impl.h b/content/browser/renderer_host/render_widget_host_impl.h
index 3cefbd833b01826378c28061884c958205b22eaf..b82f30b950fde41e504b124d8c8f22c73739eac3 100644
--- a/content/browser/renderer_host/render_widget_host_impl.h
+++ b/content/browser/renderer_host/render_widget_host_impl.h
@@ -455,10 +455,7 @@ class CONTENT_EXPORT RenderWidgetHostImpl : public RenderWidgetHost,
   bool GotResponseToLockMouseRequest(bool allowed);
 
   // Called by the view in response to OnSwapCompositorFrame.
-  static void SendReclaimCompositorResources(
-      int32_t route_id,
-      uint32_t compositor_frame_sink_id,
-      int renderer_host_id,
+  void SendReclaimCompositorResources(
       bool is_swap_ack,
       const cc::ReturnedResourceArray& resources);
 
@@ -577,6 +574,10 @@ class CONTENT_EXPORT RenderWidgetHostImpl : public RenderWidgetHost,
   // renderer unless it is for an immediate request.
   void RequestCompositionUpdates(bool immediate_request, bool monitor_updates);
 
+  // Submits the frame received from RenderWidget.
+  void SubmitCompositorFrame(const cc::LocalSurfaceId& local_surface_id,
+                             cc::CompositorFrame frame);
+
  protected:
   // ---------------------------------------------------------------------------
   // The following method is overridden by RenderViewHost to send upwards to
@@ -929,10 +930,18 @@ class CONTENT_EXPORT RenderWidgetHostImpl : public RenderWidgetHost,
   std::unique_ptr<device::PowerSaveBlocker> power_save_blocker_;
 #endif
 
+  // These information are used to verify that the renderer does not misbehave
+  // when it comes to allocating LocalSurfaceIds. If frame size or device scale
+  // factor change, a new LocalSurfaceId must be created.
   cc::LocalSurfaceId last_local_surface_id_;
   gfx::Size last_frame_size_;
   float last_device_scale_factor_;
 
+  // Each instance of RendererCompositorFrameSink has an ID that we keep track
+  // of so we can tell when a new instance has been created for the purpose of
+  // not returning stale resources.
+  uint32_t last_compositor_frame_sink_id_ = 0;
+
   base::WeakPtrFactory<RenderWidgetHostImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostImpl);