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

content/browser/renderer_host/offscreen_canvas_compositor_frame_sink_provider_impl.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_OFFSCREEN_CANVAS_COMPOSITOR_FRAME_SINK_PROVIDER_IMPL_H_
 #define CONTENT_BROWSER_RENDERER_HOST_OFFSCREEN_CANVAS_COMPOSITOR_FRAME_SINK_PROVIDER_IMPL_H_
 
 #include <unordered_map>
 
 #include "content/browser/renderer_host/offscreen_canvas_compositor_frame_sink.h"
@@ skipping 15 matching lines @@
   // blink::mojom::OffscreenCanvasCompositorFrameSinkProvider implementation.
   void CreateCompositorFrameSink(
       const cc::FrameSinkId& frame_sink_id,
       cc::mojom::MojoCompositorFrameSinkClientPtr client,
       cc::mojom::MojoCompositorFrameSinkRequest request) override;
 
   cc::SurfaceManager* GetSurfaceManager();
 
   void OnCompositorFrameSinkClientConnectionLost(
       const cc::FrameSinkId& frame_sink_id);
+  void OnCompositorFrameSinkClientDestroyed(
+      const cc::FrameSinkId& frame_sink_id);
 
  private:
   std::unordered_map<cc::FrameSinkId,
                      std::unique_ptr<OffscreenCanvasCompositorFrameSink>,
                      cc::FrameSinkIdHash>
       compositor_frame_sinks_;
 
   mojo::BindingSet<blink::mojom::OffscreenCanvasCompositorFrameSinkProvider>
       bindings_;
 
   DISALLOW_COPY_AND_ASSIGN(OffscreenCanvasCompositorFrameSinkProviderImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_OFFSCREEN_CANVAS_COMPOSITOR_FRAME_SINK_PROVIDER_IMPL_H_