Delete background tab IOSurfaces on Mac.

content/browser/renderer_host/render_widget_host_view_aura.h

 // Copyright (c) 2012 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_RENDER_WIDGET_HOST_VIEW_AURA_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_
 #pragma once
 
 #include <map>
 #include <vector>
@@ skipping 91 matching lines @@
       skia::PlatformCanvas* output,
       base::Callback<void(bool)> callback) OVERRIDE;
   virtual void OnAcceleratedCompositingStateChange() OVERRIDE;
   virtual void AcceleratedSurfaceBuffersSwapped(
       const GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params& params,
       int gpu_host_id) OVERRIDE;
   virtual void AcceleratedSurfacePostSubBuffer(
       const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params,
       int gpu_host_id) OVERRIDE;
   virtual void AcceleratedSurfaceSuspend() OVERRIDE;
+  virtual bool HasAcceleratedSurface(const gfx::Size& desired_size) OVERRIDE;
   virtual void AcceleratedSurfaceNew(
       int32 width,
       int32 height,
       uint64* surface_id,
       TransportDIB::Handle* surface_handle) OVERRIDE;
   virtual void AcceleratedSurfaceRelease(uint64 surface_id) OVERRIDE;
   virtual void GetScreenInfo(WebKit::WebScreenInfo* results) OVERRIDE;
   virtual gfx::Rect GetRootWindowBounds() OVERRIDE;
   virtual void ProcessTouchAck(WebKit::WebInputEvent::Type type,
                                bool processed) OVERRIDE;
@@ skipping 178 matching lines @@
   // These locks are the ones waiting for a texture of the right size to come
   // back from the renderer/GPU process.
   std::vector<linked_ptr<ResizeLock> > resize_locks_;
   // These locks are the ones waiting for a frame to be drawn.
   std::vector<linked_ptr<ResizeLock> > locks_pending_draw_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAura);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_