Fixed the crash when adding a chromium sink to remote audio track or

content/browser/renderer_host/media/media_stream_track_metrics_host.cc

Index: content/browser/renderer_host/media/media_stream_track_metrics_host.cc
diff --git a/content/browser/renderer_host/media/media_stream_track_metrics_host.cc b/content/browser/renderer_host/media/media_stream_track_metrics_host.cc
index 9bae1f728392d8a99c5f5399a7e398021649e45e..328d60e28acf2cd49864f87ad997faa72aebfcb5 100644
--- a/content/browser/renderer_host/media/media_stream_track_metrics_host.cc
+++ b/content/browser/renderer_host/media/media_stream_track_metrics_host.cc
@@ -49,13 +49,16 @@ bool MediaStreamTrackMetricsHost::OnMessageReceived(
 void MediaStreamTrackMetricsHost::OnAddTrack(uint64 id,
                                              bool is_audio,
                                              bool is_remote) {
-  DCHECK(tracks_.find(id) == tracks_.end());
+  if (tracks_.find(id) != tracks_.end())
+    return;
+
   TrackInfo info = {is_audio, is_remote, base::TimeTicks::Now()};
   tracks_[id] = info;
 }
 
 void MediaStreamTrackMetricsHost::OnRemoveTrack(uint64 id) {
-  DCHECK(tracks_.find(id) != tracks_.end());
+  if (tracks_.find(id) == tracks_.end())
+    return;
 
   TrackInfo& info = tracks_[id];
   ReportDuration(info);