Propagate muted state from MediaStreamAudioSource into JS.

content/renderer/media/media_stream_source.cc

Index: content/renderer/media/media_stream_source.cc
diff --git a/content/renderer/media/media_stream_source.cc b/content/renderer/media/media_stream_source.cc
index 3334bfd57120d66fa4bbd13cac1a12a50d968479..97b34d8340b39df103fc558cfc74d61e3734890f 100644
--- a/content/renderer/media/media_stream_source.cc
+++ b/content/renderer/media/media_stream_source.cc
@@ -26,6 +26,14 @@ void MediaStreamSource::StopSource() {
   Owner().SetReadyState(blink::WebMediaStreamSource::kReadyStateEnded);
 }
 
+void MediaStreamSource::SetSourceMuted(bool is_muted) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  // TODO(ossu): Check that we only go between Muted and Live, not from Ended.

[miu, 2017/06/19 19:40:37]

Instead of this TODO, why not:

  DCHECK_NE(readyState(), kReadyStateEnded);
 

[ossu-chromium, 2017/06/26 16:06:14]

I considered that but am a bit worried that we may hit such a DCHECK if the
muted state changes just as the stream ends. The blink code seems to already
discard any readyState changes if it's already at ended. I'm considering just
making a note of that in a comment here, instead.

[miu, 2017/06/26 23:01:08]

Nice! No TODO here anymore. :)

+  Owner().SetReadyState(is_muted
+                            ? blink::WebMediaStreamSource::kReadyStateMuted
+                            : blink::WebMediaStreamSource::kReadyStateLive);
+}
+
 void MediaStreamSource::SetDeviceInfo(const StreamDeviceInfo& device_info) {
   DCHECK(thread_checker_.CalledOnValidThread());
   device_info_ = device_info;