Replace MessageLoopProxy with SingleThreadTaskRunner for media/filters/ + associated code.

media/filters/ffmpeg_demuxer.h

Index: media/filters/ffmpeg_demuxer.h
diff --git a/media/filters/ffmpeg_demuxer.h b/media/filters/ffmpeg_demuxer.h
index 04a39e57d40b9a94d1f6b75d0ba213ab3ff357bb..f0b911403dc5106a7833e5a3515464a9f12d39fc 100644
--- a/media/filters/ffmpeg_demuxer.h
+++ b/media/filters/ffmpeg_demuxer.h
@@ -56,7 +56,10 @@ class FFmpegDemuxerStream : public DemuxerStream {
  public:
   // Keeps a copy of |demuxer| and initializes itself using information
   // inside |stream|.  Both parameters must outlive |this|.
-  FFmpegDemuxerStream(FFmpegDemuxer* demuxer, AVStream* stream);
+  FFmpegDemuxerStream(
+      FFmpegDemuxer* demuxer,
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+      AVStream* stream);
   virtual ~FFmpegDemuxerStream();
 
   // Enqueues the given AVPacket. It is invalid to queue a |packet| after
@@ -105,7 +108,7 @@ class FFmpegDemuxerStream : public DemuxerStream {
                                                 int64 timestamp);
 
   FFmpegDemuxer* demuxer_;
-  scoped_refptr<base::MessageLoopProxy> message_loop_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   AVStream* stream_;
   AudioDecoderConfig audio_config_;
   VideoDecoderConfig video_config_;
@@ -128,7 +131,7 @@ class FFmpegDemuxerStream : public DemuxerStream {
 
 class MEDIA_EXPORT FFmpegDemuxer : public Demuxer {
  public:
-  FFmpegDemuxer(const scoped_refptr<base::MessageLoopProxy>& message_loop,
+  FFmpegDemuxer(const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
                 DataSource* data_source,
                 const NeedKeyCB& need_key_cb,
                 const scoped_refptr<MediaLog>& media_log);
@@ -186,7 +189,7 @@ class MEDIA_EXPORT FFmpegDemuxer : public Demuxer {
 
   DemuxerHost* host_;
 
-  scoped_refptr<base::MessageLoopProxy> message_loop_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   base::WeakPtrFactory<FFmpegDemuxer> weak_factory_;
   base::WeakPtr<FFmpegDemuxer> weak_this_;