Add VideoTrackSink interface to content/public

content/renderer/media/media_stream_video_track.h

Index: content/renderer/media/media_stream_video_track.h
diff --git a/content/renderer/media/media_stream_video_track.h b/content/renderer/media/media_stream_video_track.h
new file mode 100644
index 0000000000000000000000000000000000000000..70aa8fa4d7394cb3e13d08dd1196426bcfbd76dc
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+++ b/content/renderer/media/media_stream_video_track.h
@@ -0,0 +1,48 @@
+// Copyright 2013 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_TRACK_H_
+#define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_TRACK_H_
+
+#include "base/compiler_specific.h"
+#include "base/memory/scoped_vector.h"
+#include "base/threading/thread_checker.h"
+#include "content/common/content_export.h"
+#include "content/public/renderer/media_stream_video_sink.h"
+#include "content/renderer/media/media_stream_track_extra_data.h"
+
+namespace webrtc {
+class VideoTrackInterface;
+}
+
+namespace content {
+
+class WebRtcVideoSinkAdapter;
+
+// MediaStreamVideoTrack is a video specific representation of a
+// blink::WebMediaStreamTrack in content. It is owned by the blink object
+// and can be retrieved from a blink object using
+// WebMediaStreamTrack::extraData()
+class CONTENT_EXPORT MediaStreamVideoTrack : public MediaStreamTrackExtraData {
+ public:
+  explicit MediaStreamVideoTrack(webrtc::VideoTrackInterface* track);
+  virtual ~MediaStreamVideoTrack();
+  void AddSink(MediaStreamVideoSink* sink);
+  void RemoveSink(MediaStreamVideoSink* sink);
+
+ private:
+  // Used to DCHECK that we are called on the correct thread.
+  base::ThreadChecker thread_checker_;
+  // The webrtc video track.
+  // TODO(perkj): Make this class independent of webrtc as part of project
+  // Piranha Plant.
+  webrtc::VideoTrackInterface* video_track_;
+  ScopedVector<WebRtcVideoSinkAdapter> sinks_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaStreamVideoTrack);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_VIDEO_TRACK_H_