[Experiment] Alpha Channel Support

api/video_codecs/video_decoder.h

 /*
  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 64 matching lines @@
   virtual int32_t Release() = 0;
 
   // Returns true if the decoder prefer to decode frames late.
   // That is, it can not decode infinite number of frames before the decoded
   // frame is consumed.
   virtual bool PrefersLateDecoding() const { return true; }
 
   virtual const char* ImplementationName() const { return "unknown"; }
 };
 
+class VideoDecoderFactoryEx {
+ public:
+  virtual VideoDecoder* Create() = 0;
+  virtual void Destroy(VideoDecoder* decoder) = 0;
+  virtual ~VideoDecoderFactoryEx() {}
+};
+
 }  // namespace webrtc
 
 #endif  // API_VIDEO_CODECS_VIDEO_DECODER_H_