Handle early destruction of CanvasCaptureHandler

content/renderer/media/canvas_capture_handler.h

 // Copyright 2015 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_RENDERER_MEDIA_CANVAS_CAPTURE_HANDLER_H_
 #define CONTENT_RENDERER_MEDIA_CANVAS_CAPTURE_HANDLER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 54 matching lines @@
       const blink::WebSize& size,
       double frame_rate,
       const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
       blink::WebMediaStreamTrack* track);
 
   void CreateNewFrame(const SkImage* image);
   void AddVideoCapturerSourceToVideoTrack(
       scoped_ptr<media::VideoCapturerSource> source,
       blink::WebMediaStreamTrack* web_track);
 
-  // Implementation VideoCapturerSource that is owned by Blink and delegates
-  // the Start/Stop calls to CanvasCaptureHandler.
-  class VideoCapturerSource;
-
   // Object that does all the work of running |new_frame_callback_|.
   // Destroyed on |frame_callback_task_runner_| after the class is destroyed.
   class CanvasCaptureHandlerDelegate;
 
   media::VideoCaptureFormat capture_format_;
   bool ask_for_new_frame_;
 
   const blink::WebSize size_;
   gfx::Size last_size;
   std::vector<uint8_t> temp_data_;
   size_t row_bytes_;
   SkImageInfo image_info_;
   media::VideoFramePool frame_pool_;
 
   const scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
   scoped_ptr<CanvasCaptureHandlerDelegate> delegate_;
 
   // Bound to Main Render thread.
   base::ThreadChecker main_render_thread_checker_;
   base::WeakPtrFactory<CanvasCaptureHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CanvasCaptureHandler);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_CANVAS_CAPTURE_HANDLER_H_