media: Introduce DemuxerStreamProvider interface.

media/filters/ffmpeg_demuxer.cc

Index: media/filters/ffmpeg_demuxer.cc
diff --git a/media/filters/ffmpeg_demuxer.cc b/media/filters/ffmpeg_demuxer.cc
index 171d70a1c8023153fa576c14965f94f49e34da33..9df765e8f161c4051c804c81fea7be5e090a357c 100644
--- a/media/filters/ffmpeg_demuxer.cc
+++ b/media/filters/ffmpeg_demuxer.cc
@@ -652,6 +652,10 @@ void FFmpegDemuxer::Initialize(DemuxerHost* host,
                  status_cb));
 }
 
+base::Time FFmpegDemuxer::GetTimelineOffset() const {
+  return timeline_offset_;
+}
+
 DemuxerStream* FFmpegDemuxer::GetStream(DemuxerStream::Type type) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   return GetFFmpegStream(type);
@@ -668,10 +672,6 @@ FFmpegDemuxerStream* FFmpegDemuxer::GetFFmpegStream(
   return NULL;
 }
 
-base::Time FFmpegDemuxer::GetTimelineOffset() const {
-  return timeline_offset_;
-}
-
 Demuxer::Liveness FFmpegDemuxer::GetLiveness() const {
   DCHECK(task_runner_->BelongsToCurrentThread());
   return liveness_;