Implement disabling and enabling media tracks

chromecast/renderer/media/cma_renderer.cc

Index: chromecast/renderer/media/cma_renderer.cc
diff --git a/chromecast/renderer/media/cma_renderer.cc b/chromecast/renderer/media/cma_renderer.cc
index 0cdd1aa6f2d8669ebf6ea1fc73c10ee2ba69c9ae..0b37f9546b9339a0788783b7ed02f73101239ec4 100644
--- a/chromecast/renderer/media/cma_renderer.cc
+++ b/chromecast/renderer/media/cma_renderer.cc
@@ -172,6 +172,11 @@ void CmaRenderer::StartPlayingFrom(base::TimeDelta time) {
   CompleteStateTransition(kPlaying);
 }
 
+void CmaRenderer::RestartStreamPlayback(::media::DemuxerStream* stream,
+                                        base::TimeDelta time) {
+  NOTIMPLEMENTED();
+}
+
 void CmaRenderer::SetPlaybackRate(double playback_rate) {
   CMALOG(kLogControl) << __FUNCTION__ << ": " << playback_rate;
   DCHECK(thread_checker_.CalledOnValidThread());