Protect Update{Audio|Video}Config() by lock in ChunkDemuxerStream.

media/filters/chunk_demuxer.cc

Index: media/filters/chunk_demuxer.cc
diff --git a/media/filters/chunk_demuxer.cc b/media/filters/chunk_demuxer.cc
index fd44eb8ac48233a6fbd55a75ed0f5271d1acaccc..40172fedfe097510ffecef6e9f45a4286d3ed64a 100644
--- a/media/filters/chunk_demuxer.cc
+++ b/media/filters/chunk_demuxer.cc
@@ -361,12 +361,14 @@ Ranges<TimeDelta> ChunkDemuxerStream::GetBufferedRanges(
 bool ChunkDemuxerStream::UpdateAudioConfig(const AudioDecoderConfig& config) {
   DCHECK(config.IsValidConfig());
   DCHECK_EQ(type_, AUDIO);
+  base::AutoLock auto_lock(lock_);
   return stream_->UpdateAudioConfig(config);
 }
 
 bool ChunkDemuxerStream::UpdateVideoConfig(const VideoDecoderConfig& config) {
   DCHECK(config.IsValidConfig());
   DCHECK_EQ(type_, VIDEO);
+  base::AutoLock auto_lock(lock_);
   return stream_->UpdateVideoConfig(config);
 }