Add video decoding methods in Decryptor and add DecryptingVideoDecoder.

media/filters/ffmpeg_video_decoder.h

 // Copyright (c) 2012 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 MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
 #define MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/decryptor.h"
@@ skipping 32 matching lines @@
   int GetVideoBuffer(AVCodecContext *codec_context, AVFrame* frame);
 
  protected:
   virtual ~FFmpegVideoDecoder();
 
  private:
   enum DecoderState {
     kUninitialized,
     kNormal,
     kFlushCodec,
-    kDecodeFinished,
+    kDecodeFinished
   };
 
   // Carries out the reading operation scheduled by Read().
   void DoRead(const ReadCB& read_cb);
 
   // Reads from the demuxer stream with corresponding callback method.
   void ReadFromDemuxerStream();
   void DecryptOrDecodeBuffer(DemuxerStream::Status status,
                              const scoped_refptr<DecoderBuffer>& buffer);
 
@@ skipping 51 matching lines @@
   scoped_refptr<DemuxerStream> demuxer_stream_;
 
   Decryptor* decryptor_;
 
   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_