Remove usage of FOR_EACH_OBSERVER macro in media/

media/audio/audio_manager_base.cc

Index: media/audio/audio_manager_base.cc
diff --git a/media/audio/audio_manager_base.cc b/media/audio/audio_manager_base.cc
index 7d3c946ab179221bd42e7525e0ecf3cc77b5c8b3..944156c66c6f8e9eb1e561ea1896b01a9c05a083 100644
--- a/media/audio/audio_manager_base.cc
+++ b/media/audio/audio_manager_base.cc
@@ -320,7 +320,8 @@ void AudioManagerBase::RemoveOutputDeviceChangeListener(
 void AudioManagerBase::NotifyAllOutputDeviceChangeListeners() {
   DCHECK(GetTaskRunner()->BelongsToCurrentThread());
   DVLOG(1) << "Firing OnDeviceChange() notifications.";
-  FOR_EACH_OBSERVER(AudioDeviceListener, output_listeners_, OnDeviceChange());
+  for (auto& observer : output_listeners_)
+    observer.OnDeviceChange();
 }
 
 AudioParameters AudioManagerBase::GetDefaultOutputStreamParameters() {