Remove TrayAudioDelegate

ash/common/system/chromeos/audio/tray_audio.h

Index: ash/common/system/chromeos/audio/tray_audio.h
diff --git a/ash/common/system/chromeos/audio/tray_audio.h b/ash/common/system/chromeos/audio/tray_audio.h
index d58764476eb9d9989e509d51f1623704187d6e2a..5ad0106050000c571d7700e751fae093f5af79b7 100644
--- a/ash/common/system/chromeos/audio/tray_audio.h
+++ b/ash/common/system/chromeos/audio/tray_audio.h
@@ -18,10 +18,6 @@
 
 namespace ash {
 
-namespace system {
-class TrayAudioDelegate;
-}
-
 namespace tray {
 class AudioDetailedView;
 class VolumeView;
@@ -76,8 +72,6 @@ class ASH_EXPORT TrayAudio : public TrayImageItem,
   // Updates the UI views.
   void Update();
 
-  // TODO(jamescook): Remove this delegate and inline all the code.
-  std::unique_ptr<system::TrayAudioDelegate> audio_delegate_;
   tray::VolumeView* volume_view_;
 
   // True if VolumeView should be created for accelerator pop up;