Replaced BackgroundAnimator with ShelfBackgroundAnimator.

ash/system/tray/tray_background_view.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ASH_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_
 #define ASH_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
@@ skipping 66 matching lines @@
   void ChildPreferredSizeChanged(views::View* child) override;
   void GetAccessibleState(ui::AXViewState* state) override;
   void AboutToRequestFocusFromTabTraversal(bool reverse) override;
 
   // ActionableView:
   bool PerformAction(const ui::Event& event) override;
   gfx::Rect GetFocusBounds() override;
   void OnGestureEvent(ui::GestureEvent* event) override;
 
   // BackgroundAnimatorDelegate:
-  void UpdateBackground(int alpha) override;
+  void UpdateBackground(BackgroundAnimator* animator, int alpha) override;
 
   // Called whenever the shelf alignment changes.
   virtual void SetShelfAlignment(ShelfAlignment alignment);
 
   // Called when the anchor (tray or bubble) may have moved or changed.
   virtual void AnchorUpdated() {}
 
   // Called from GetAccessibleState, must return a valid accessible name.
   virtual base::string16 GetAccessibleNameForTray() = 0;
 
@@ skipping 80 matching lines @@
 
   std::unique_ptr<TrayWidgetObserver> widget_observer_;
   std::unique_ptr<TrayEventFilter> tray_event_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(TrayBackgroundView);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_