Fix regression with audio mirroring due to observers being added while iterating over the list of ob

media/audio/audio_output_controller.cc

Index: media/audio/audio_output_controller.cc
diff --git a/media/audio/audio_output_controller.cc b/media/audio/audio_output_controller.cc
index a9dd2c855c340ade8a95443a54418013f88cc6fd..b195fa633f915b47ec8a675ff6d8287033e7295a 100644
--- a/media/audio/audio_output_controller.cc
+++ b/media/audio/audio_output_controller.cc
@@ -141,7 +141,8 @@ void AudioOutputController::DoCreate() {
 
   // Everything started okay, so register for state change callbacks if we have
   // not already done so.
-  audio_manager_->AddOutputDeviceChangeListener(this);
+  if (state_ != kRecreating)

[miu, 2013/01/04 21:57:56]

This will leave us in a state where AOC is not registered as a device change
listener.  That's because DoStopCloseAndClearStream() calls
RemoveOutputDeviceChangeListener() whether we're re-creating or not.  So, we
unconditionally want to call AddOutputDeviceChangeListener here.

It looks like this change is just covering up another bug somewhere?

[justinlin, 2013/01/04 22:31:02]

Right. Hmm, I saw a DCHECK failure due to this (observer registering twice), but
that may be when I was debugging. Yea, I see the problem now, it's getting into
an infinite OnDeviceChanged loop for some reason. Will update patch soon with a
better solution.

+    audio_manager_->AddOutputDeviceChangeListener(this);
 
   // We have successfully opened the stream. Set the initial volume.
   stream_->SetVolume(volume_);