Refactor VideoCapturerDelegate to use WeakPtr instead of refcount.

content/renderer/media/media_stream_video_capturer_source.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_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_CAPTURER_SOURCE_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_CAPTURER_SOURCE_H_
 
 #include "base/callback.h"
 #include "base/gtest_prod_util.h"
+#include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/threading/thread_checker.h"
 #include "content/common/media/video_capture.h"
 #include "content/renderer/media/media_stream_video_source.h"
 
 namespace content {
 
 // VideoCapturerDelegate is a delegate used by MediaStreamVideoCapturerSource
 // for local video capturer. It uses VideoCaptureImplManager to start / stop
 // and receive I420 frames from Chrome's video capture implementation.
 //
 // This is a render thread only object.
-class CONTENT_EXPORT VideoCapturerDelegate
-    : public base::RefCountedThreadSafe<VideoCapturerDelegate> {
+class CONTENT_EXPORT VideoCapturerDelegate {
  public:
   typedef base::Callback<void(MediaStreamRequestResult result)> RunningCallback;
 
   explicit VideoCapturerDelegate(const StreamDeviceInfo& device_info);
+  virtual ~VideoCapturerDelegate();
 
   // Collects the formats that can currently be used.
   // |max_requested_height|, |max_requested_width|, and
   // |max_requested_frame_rate| is used by Tab and Screen capture to decide what
   // resolution/framerate to generate. |callback| is triggered when the formats
   // have been collected.
   virtual void GetCurrentSupportedFormats(
       int max_requested_width,
       int max_requested_height,
       double max_requested_frame_rate,
@@ skipping 12 matching lines @@
 
   // Stops capturing frames and clears all callbacks including the
   // SupportedFormatsCallback callback.
   virtual void StopCapture();
 
  private:
   FRIEND_TEST_ALL_PREFIXES(MediaStreamVideoCapturerSourceTest, Ended);
   friend class base::RefCountedThreadSafe<VideoCapturerDelegate>;
   friend class MockVideoCapturerDelegate;
 
-  virtual ~VideoCapturerDelegate();
-
   void OnStateUpdateOnRenderThread(VideoCaptureState state);
   void OnDeviceFormatsInUseReceived(const media::VideoCaptureFormats& formats);
   void OnDeviceSupportedFormatsEnumerated(
       const media::VideoCaptureFormats& formats);
 
   // The id identifies which video capture device is used for this video
   // capture session.
   media::VideoCaptureSessionId session_id_;
   base::Closure release_device_cb_;
   base::Closure stop_capture_cb_;
 
   bool is_screen_cast_;
 
   // |running_callback| is provided to this class in StartCapture and must be
   // valid until StopCapture is called.
   RunningCallback running_callback_;
 
   VideoCaptureDeviceFormatsCB source_formats_callback_;
 
   // Bound to the render thread.
   base::ThreadChecker thread_checker_;
 
+  base::WeakPtrFactory<VideoCapturerDelegate> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(VideoCapturerDelegate);
 };
 
 // Owned by WebMediaStreamSource in Blink as a representation of a video
 // stream coming from a camera.
 // This is a render thread only object. All methods must be called on the
 // render thread.
 class CONTENT_EXPORT MediaStreamVideoCapturerSource
     : public MediaStreamVideoSource {
  public:
   MediaStreamVideoCapturerSource(
       const StreamDeviceInfo& device_info,
       const SourceStoppedCallback& stop_callback,
-      const scoped_refptr<VideoCapturerDelegate>& delegate);
+      scoped_ptr<VideoCapturerDelegate> delegate);
 
   virtual ~MediaStreamVideoCapturerSource();
 
  protected:
   // Implements MediaStreamVideoSource.
   void GetCurrentSupportedFormats(
       int max_requested_width,
       int max_requested_height,
       double max_requested_frame_rate,
       const VideoCaptureDeviceFormatsCB& callback) override;
 
   void StartSourceImpl(
       const media::VideoCaptureFormat& format,
       const VideoCaptureDeliverFrameCB& frame_callback) override;
 
   void StopSourceImpl() override;
 
  private:
   // The delegate that provides video frames.
-  scoped_refptr<VideoCapturerDelegate> delegate_;
+  scoped_ptr<VideoCapturerDelegate> delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamVideoCapturerSource);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_CAPTURER_SOURCE_H_