Allow muting/unmuting audio through media track API

media/blink/websourcebuffer_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/blink/websourcebuffer_impl.h"
 
 #include <stdint.h>
 
 #include <cmath>
 #include <limits>
@@ skipping 171 matching lines @@
     trackInfoVector.push_back(
         std::make_tuple(mediaTrackTypeToBlink(track->type()),
                         blink::WebString::fromUTF8(track->id()),
                         blink::WebString::fromUTF8(track->kind()),
                         blink::WebString::fromUTF8(track->label()),
                         blink::WebString::fromUTF8(track->language())));
   }
 
   std::vector<blink::WebMediaPlayer::TrackId> blinkTrackIds =
       client_->initializationSegmentReceived(trackInfoVector);
+
+  DCHECK_EQ(blinkTrackIds.size(), tracks->tracks().size());
+  for (size_t i = 0; i < blinkTrackIds.size(); ++i) {
+    demuxer_->OnTrackIdAssigned(blinkTrackIds[i], tracks->tracks()[i].get());
+  }
 }
 
 }  // namespace media