Mac ÜC: Enable GPU back-pressure from the browser to the renderer

content/browser/compositor/delegated_frame_host.h

 // Copyright 2014 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_COMPOSITOR_DELEGATED_FRAME_HOST_H_
 #define CONTENT_BROWSER_COMPOSITOR_DELEGATED_FRAME_HOST_H_
 
 #include "cc/layers/delegated_frame_provider.h"
 #include "cc/layers/delegated_frame_resource_collection.h"
 #include "cc/output/copy_output_result.h"
@@ skipping 24 matching lines @@
 
 // The DelegatedFrameHostClient is the interface from the DelegatedFrameHost,
 // which manages delegated frames, and the ui::Compositor being used to
 // display them.
 class CONTENT_EXPORT DelegatedFrameHostClient {
  public:
   virtual ui::Compositor* GetCompositor() const = 0;
   virtual ui::Layer* GetLayer() = 0;
   virtual RenderWidgetHostImpl* GetHost() = 0;
   virtual void SchedulePaintInRect(const gfx::Rect& damage_rect_in_dip) = 0;
+  virtual void DelegatedCompositorDidSwapBuffers() = 0;
+  virtual void DelegatedCompositorAbortedSwapBuffers() = 0;
   virtual bool IsVisible() = 0;
   virtual scoped_ptr<ResizeLock> CreateResizeLock(
       bool defer_compositor_lock) = 0;
   virtual gfx::Size DesiredFrameSize() = 0;
 
   // TODO(ccameron): It is likely that at least one of these two functions is
   // redundant. Find which one, and delete it.
   virtual float CurrentDeviceScaleFactor() = 0;
   virtual gfx::Size ConvertViewSizeToPixel(const gfx::Size& size) = 0;
 
@@ skipping 222 matching lines @@
   // YUV readback pipeline.
   scoped_ptr<content::ReadbackYUVInterface>
       yuv_readback_pipeline_;
 
   scoped_ptr<DelegatedFrameEvictor> delegated_frame_evictor_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_DELEGATED_FRAME_HOST_H_