Mac: Fix bad framerate when capturing tab

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 87 matching lines @@
       const SkColorType color_type);
   void CopyFromCompositingSurfaceToVideoFrame(
       const gfx::Rect& src_subrect,
       const scoped_refptr<media::VideoFrame>& target,
       const base::Callback<void(bool)>& callback);
   bool CanCopyToVideoFrame() const;
   bool CanSubscribeFrame() const;
   void BeginFrameSubscription(
       scoped_ptr<RenderWidgetHostViewFrameSubscriber> subscriber);
   void EndFrameSubscription();
+  bool HasFrameSubscriber() const { return frame_subscriber_; }
 
   // Exposed for tests.
   cc::DelegatedFrameProvider* FrameProviderForTesting() const {
     return frame_provider_.get();
   }
   void OnCompositingDidCommitForTesting(ui::Compositor* compositor) {
     OnCompositingDidCommit(compositor);
   }
   bool ShouldCreateResizeLockForTesting() { return ShouldCreateResizeLock(); }
 
@@ skipping 158 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_