OffscreenCanvasCompositorFrameSink uses CompositorFrameSinkSupport

content/browser/renderer_host/offscreen_canvas_compositor_frame_sink_provider_impl.cc

 // 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.
 
 #include "content/browser/renderer_host/offscreen_canvas_compositor_frame_sink_provider_impl.h"
 
+#include "content/browser/compositor/surface_utils.h"
 #include "content/browser/renderer_host/offscreen_canvas_compositor_frame_sink.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 
 namespace content {
 
 OffscreenCanvasCompositorFrameSinkProviderImpl::
     OffscreenCanvasCompositorFrameSinkProviderImpl() {}
 
 OffscreenCanvasCompositorFrameSinkProviderImpl::
     ~OffscreenCanvasCompositorFrameSinkProviderImpl() {}
 
 // static
 void OffscreenCanvasCompositorFrameSinkProviderImpl::Create(
     blink::mojom::OffscreenCanvasCompositorFrameSinkProviderRequest request) {
   mojo::MakeStrongBinding(
       base::MakeUnique<OffscreenCanvasCompositorFrameSinkProviderImpl>(),
       std::move(request));
 }
 
 void OffscreenCanvasCompositorFrameSinkProviderImpl::CreateCompositorFrameSink(
     const cc::SurfaceId& surface_id,

[xlai (Olivia), 2016/12/14 16:58:56]

I have one concern here. The SurfaceId is provided when CompositorFrameSink is
created; but your patch drops the LocalFrameId component. Will it be right if
CompositorFrameSinkProvider::CreateCompositorFrameSink only passes FrameSinkId,
and the LocalFrameId is only passed in SubmitCompositorFrame?

[Fady Samuel, 2016/12/14 17:00:23]

Yes, that should be fine.

     cc::mojom::MojoCompositorFrameSinkClientPtr client,
     cc::mojom::MojoCompositorFrameSinkRequest request) {
-  OffscreenCanvasCompositorFrameSink::Create(surface_id, std::move(client),
-                                             std::move(request));
+  OffscreenCanvasCompositorFrameSink::Create(
+      surface_id.frame_sink_id(), GetSurfaceManager(), std::move(client),
+      std::move(request));
 }
 
 }  // namespace content