Consolidate volume control code.

ash/accelerators/accelerator_controller.h

Index: ash/accelerators/accelerator_controller.h
diff --git a/ash/accelerators/accelerator_controller.h b/ash/accelerators/accelerator_controller.h
index 77769ec4949bd8d4083da7ca5d58032b4c6301b6..1f18a00de0186ed6818bb57daecff5fc695d5920 100644
--- a/ash/accelerators/accelerator_controller.h
+++ b/ash/accelerators/accelerator_controller.h
@@ -83,17 +83,10 @@ class ASH_EXPORT AcceleratorController : public ui::AcceleratorTarget {
       keyboard_brightness_control_delegate);
   void SetScreenshotDelegate(
       scoped_ptr<ScreenshotDelegate> screenshot_delegate);
-  void SetVolumeControlDelegate(
-      scoped_ptr<VolumeControlDelegate> volume_control_delegate);
-
   BrightnessControlDelegate* brightness_control_delegate() const {
     return brightness_control_delegate_.get();
   }
 
-  VolumeControlDelegate* volume_control_delegate() const {
-    return volume_control_delegate_.get();
-  }
-
  private:
   // Initializes the accelerators this class handles as a target.
   void Init();
@@ -116,7 +109,6 @@ class ASH_EXPORT AcceleratorController : public ui::AcceleratorTarget {
   scoped_ptr<KeyboardBrightnessControlDelegate>
       keyboard_brightness_control_delegate_;
   scoped_ptr<ScreenshotDelegate> screenshot_delegate_;
-  scoped_ptr<VolumeControlDelegate> volume_control_delegate_;
 
   // A map from accelerators to the AcceleratorAction values, which are used in
   // the implementation.