Separate DemuxerHost from DataSourceHost.

media/base/pipeline.cc

Index: media/base/pipeline.cc
diff --git a/media/base/pipeline.cc b/media/base/pipeline.cc
index 8c0ca54431885e8393e6d8911d60792c496d696f..f2b6ea742ff28696037fcb2d0758f3f75d84777d 100644
--- a/media/base/pipeline.cc
+++ b/media/base/pipeline.cc
@@ -374,7 +374,6 @@ void Pipeline::SetDuration(TimeDelta duration) {
 }
 
 void Pipeline::SetTotalBytes(int64 total_bytes) {
-  DCHECK(IsRunning());

[scherkus (not reviewing), 2014/03/26 21:50:12]

I'm assuming these DCHECKs were getting hit, right?

[sandersd (OOO until July 31), 2014/03/26 22:11:12]

I didn't check. Before these calls were delayed until after
Pipeline::InitializeDemuxer() (that's where the host gets passed), but now it
happens as soon as the BufferedDataSource's Loader starts (which I believe
happens strictly before the pipeline is started for FFmpeg, in parallel for
MSE).

   media_log_->AddEvent(
       media_log_->CreateStringEvent(
           MediaLogEvent::TOTAL_BYTES_SET, "total_bytes",
@@ -685,7 +684,6 @@ void Pipeline::OnStopCompleted(PipelineStatus status) {
 }
 
 void Pipeline::AddBufferedByteRange(int64 start, int64 end) {
-  DCHECK(IsRunning());
   base::AutoLock auto_lock(lock_);
   buffered_byte_ranges_.Add(start, end);
   did_loading_progress_ = true;