Fix VideoDecoderShim to return correct decode_id for all codecs.

media/filters/ffmpeg_video_decoder.cc

 // 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.
 
 #include "media/filters/ffmpeg_video_decoder.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 216 matching lines @@
       state_ = kError;
       decode_cb_bound.Run(kDecodeError);
       return;
     }
     // Repeat to flush the decoder after receiving EOS buffer.
   } while (buffer->end_of_stream() && has_produced_frame);
 
   if (buffer->end_of_stream())
     state_ = kDecodeFinished;
 
+  // VideoDecoderShim expects that |decode_cb| is called only after
+  // |output_cb_|.
   decode_cb_bound.Run(kOk);
 }
 
 void FFmpegVideoDecoder::Reset(const base::Closure& closure) {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   avcodec_flush_buffers(codec_context_.get());
   state_ = kNormal;
   task_runner_->PostTask(FROM_HERE, closure);
 }
@@ skipping 98 matching lines @@
   if (!codec || avcodec_open2(codec_context_.get(), codec, NULL) < 0) {
     ReleaseFFmpegResources();
     return false;
   }
 
   av_frame_.reset(av_frame_alloc());
   return true;
 }
 
 }  // namespace media