Implement disabling and enabling media tracks

media/filters/decrypting_demuxer_stream.cc

Index: media/filters/decrypting_demuxer_stream.cc
diff --git a/media/filters/decrypting_demuxer_stream.cc b/media/filters/decrypting_demuxer_stream.cc
index a44a036ff26841ebfb46e4a3df9fd89ffa9c8f41..2538a80f741fff5cd69007fa300e677266cf55ef 100644
--- a/media/filters/decrypting_demuxer_stream.cc
+++ b/media/filters/decrypting_demuxer_stream.cc
@@ -152,6 +152,15 @@ VideoRotation DecryptingDemuxerStream::video_rotation() {
   return demuxer_stream_->video_rotation();
 }
 
+bool DecryptingDemuxerStream::enabled() const {
+  return demuxer_stream_->enabled();
+}
+
+void DecryptingDemuxerStream::set_enabled(bool enabled,
+                                          base::TimeDelta timestamp) {
+  demuxer_stream_->set_enabled(enabled, timestamp);
+}
+
 DecryptingDemuxerStream::~DecryptingDemuxerStream() {
   DVLOG(2) << __FUNCTION__ << " : state_ = " << state_;
   DCHECK(task_runner_->BelongsToCurrentThread());