Reland of "Apply Shelf/Dock opacity animations for the Material Design style."

ash/common/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_COMMON_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_
 #define ASH_COMMON_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
+#include "ash/common/shelf/shelf_background_animator_observer.h"
 #include "ash/common/shelf/shelf_types.h"
 #include "ash/common/system/tray/actionable_view.h"
-#include "ash/common/wm/background_animator.h"
 #include "base/macros.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/views/bubble/tray_bubble_view.h"
 
 namespace ash {
 class ShelfLayoutManager;
 class TrayEventFilter;
 class TrayBackground;
 class WmShelf;
 
 // Base class for children of StatusAreaWidget: SystemTray, WebNotificationTray,
 // LogoutButtonTray, OverviewButtonTray.
 // This class handles setting and animating the background when the Launcher
 // his shown/hidden. It also inherits from ActionableView so that the tray
 // items can override PerformAction when clicked on.
 class ASH_EXPORT TrayBackgroundView : public ActionableView,
-                                      public BackgroundAnimatorDelegate,
-                                      public ui::ImplicitAnimationObserver {
+                                      public ui::ImplicitAnimationObserver,
+                                      public ShelfBackgroundAnimatorObserver {
  public:
   static const char kViewClassName[];
 
   // Base class for tray containers. Sets the border and layout. The container
   // auto-resizes the widget when necessary.
   class TrayContainer : public views::View {
    public:
     explicit TrayContainer(ShelfAlignment alignment);
     ~TrayContainer() override {}
 
@@ skipping 34 matching lines @@
   const char* GetClassName() const override;
   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;
-
   // 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;
 
   // Called when the bubble is resized.
@@ skipping 29 matching lines @@
   bool draw_background_as_active() const { return draw_background_as_active_; }
 
   TrayContainer* tray_container() const { return tray_container_; }
   ShelfAlignment shelf_alignment() const { return shelf_alignment_; }
   TrayEventFilter* tray_event_filter() { return tray_event_filter_.get(); }
   WmShelf* shelf() { return wm_shelf_; }
 
   // Updates the arrow visibility based on the launcher visibility.
   void UpdateBubbleViewArrow(views::TrayBubbleView* bubble_view);
 
+  // ShelfBackgroundAnimatorObserver:
+  void UpdateShelfItemBackground(int alpha) override;
+
  private:
   class TrayWidgetObserver;
 
   // Called from Initialize after all status area trays have been created.
   // Sets the border based on the position of the view.
   void SetTrayBorder();
 
   // ui::ImplicitAnimationObserver:
   void OnImplicitAnimationsCompleted() override;
   bool RequiresNotificationWhenAnimatorDestroyed() const override;
@@ skipping 21 matching lines @@
 
   std::unique_ptr<TrayWidgetObserver> widget_observer_;
   std::unique_ptr<TrayEventFilter> tray_event_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(TrayBackgroundView);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_