Implementing promise-based commit for driving OffscreenCanvas animations

content/browser/renderer_host/offscreen_canvas_compositor_frame_sink.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.h"
 
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_manager.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 
@@ skipping 10 matching lines @@
           frame_sink_id, surface_manager, std::move(client));
   OffscreenCanvasCompositorFrameSink* compositor_frame_sink = impl.get();
   compositor_frame_sink->binding_ =
       mojo::MakeStrongBinding(std::move(impl), std::move(request));
 }
 
 OffscreenCanvasCompositorFrameSink::OffscreenCanvasCompositorFrameSink(
     const cc::FrameSinkId& frame_sink_id,
     cc::SurfaceManager* surface_manager,
     cc::mojom::MojoCompositorFrameSinkClientPtr client)
-    : support_(this, surface_manager, frame_sink_id, nullptr, nullptr),
-      client_(std::move(client)) {}
+    // TODO(crbug.com/): Pass a valid display so that we can get OnBeginFrame

[Stephen White, 2016/12/21 15:14:43]

Nit: bug ID?

+    // notification to drive
+    : support_(this, surface_manager, frame_sink_id, nullptr /*display*/,
+        nullptr),
+    client_(std::move(client)) {}
 
 OffscreenCanvasCompositorFrameSink::~OffscreenCanvasCompositorFrameSink() {}
 
 void OffscreenCanvasCompositorFrameSink::SetNeedsBeginFrame(
     bool needs_begin_frame) {
   support_.SetNeedsBeginFrame(needs_begin_frame);
 }
 
 void OffscreenCanvasCompositorFrameSink::SubmitCompositorFrame(
     const cc::LocalFrameId& local_frame_id,
@@ skipping 44 matching lines @@
   if (client_)
     client_->ReclaimResources(resources);
 }
 
 void OffscreenCanvasCompositorFrameSink::WillDrawSurface() {
   if (client_)
     client_->WillDrawSurface();
 }
 
 }  // namespace content