Detect AudioInputStream muting and propagate to MediaStreamAudioSource.

third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp

Index: third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
diff --git a/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp b/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
index 10c2e52354652c43602fb7dd5f62b5aeb090598b..10fb1add97279ffc66ea7e544b61d9c079eced15 100644
--- a/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
+++ b/third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp
@@ -72,6 +72,11 @@ MediaStreamTrack::MediaStreamTrack(ExecutionContext* context,
       constraints_() {
   component_->Source()->AddObserver(this);
 
+  // If the source is already non-live at this point, the observer won't have
+  // been called. Check the state manually.
+  if (ready_state_ != component_->Source()->GetReadyState())
+    SourceChangedState();

[Max Morin, 2017/06/02 09:56:05]

You seem to be calling a virtual method from the constructor which is usually
scary. Maybe you can make it final?

[ossu-chromium, 2017/06/02 10:48:00]

You're right. I actually only need to add a check for Muted and then call
component_->SetMuted(). The rest SourceChangedState will just never happen
(since the default ready_state_ is Live).

+
   if (component_->Source() &&
       component_->Source()->GetType() == MediaStreamSource::kTypeVideo) {
     // ImageCapture::create() only throws if |this| track is not of video type.