Pass more detailed audio hardware configuration information to the renderer

media/audio/mac/audio_manager_mac.h

Index: media/audio/mac/audio_manager_mac.h
===================================================================
--- media/audio/mac/audio_manager_mac.h	(revision 186233)
+++ media/audio/mac/audio_manager_mac.h	(working copy)
@@ -38,6 +38,16 @@
   virtual AudioInputStream* MakeLowLatencyInputStream(
       const AudioParameters& params, const std::string& device_id) OVERRIDE;
 
+  static bool GetDefaultOutputDevice(AudioDeviceID* device);
+
+  static bool GetDefaultOutputChannels(int* channels,
+                                       int* channels_per_frame);
+
+  static bool GetDeviceChannels(AudioDeviceID device,
+                                AudioObjectPropertyScope scope,
+                                int* channels,
+                                int* channels_per_frame);
+
  protected:
   virtual ~AudioManagerMac();