Mac: Fix bad framerate when capturing tab

content/browser/renderer_host/render_widget_host_view_mac.h

Index: content/browser/renderer_host/render_widget_host_view_mac.h
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.h b/content/browser/renderer_host/render_widget_host_view_mac.h
index deaf86d8eda76d5ed936f4adff6d05aad10a6fb1..887cb73f79b9fbfeccf6a460aa98eeaeaaab1987 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.h
+++ b/content/browser/renderer_host/render_widget_host_view_mac.h
@@ -350,6 +350,7 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   virtual SkColorType PreferredReadbackFormat() OVERRIDE;
 
   // CompositingIOSurfaceLayerClient implementation.
+  virtual bool AcceleratedLayerShouldAckImmediately() const OVERRIDE;
   virtual void AcceleratedLayerDidDrawFrame(bool succeeded) OVERRIDE;
 
   // gfx::DisplayObserver implementation.
@@ -520,6 +521,7 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   virtual DelegatedFrameHost* GetDelegatedFrameHost() const OVERRIDE;
 
   // BrowserCompositorViewMacClient implementation.
+  virtual bool BrowserCompositorViewShouldAckImmediately() const OVERRIDE;
   virtual void BrowserCompositorViewFrameSwapped(
       const std::vector<ui::LatencyInfo>& latency_info) OVERRIDE;
   virtual NSView* BrowserCompositorSuperview() OVERRIDE;