ARC Toast: Prevent onClosed event from being called multiple times

ash/system/toast/toast_overlay.h

 // Copyright 2016 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_TOAST_TOAST_OVERLAY_H_
 #define ASH_SYSTEM_TOAST_TOAST_OVERLAY_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
@@ skipping 10 matching lines @@
 namespace views {
 class Widget;
 }
 
 namespace ash {
 
 class ToastManagerTest;
 class ToastOverlayView;
 class ToastOverlayButton;
 
-class ASH_EXPORT ToastOverlay : public ui::LayerAnimationObserver {
+class ASH_EXPORT ToastOverlay : public ui::ImplicitAnimationObserver {
  public:
   class ASH_EXPORT Delegate {
    public:
     virtual ~Delegate() {}
     virtual void OnClosed() = 0;
   };
 
   ToastOverlay(Delegate* delegate, const std::string& text);
   ~ToastOverlay() override;
 
   // Shows or hides the overlay.
   void Show(bool visible);
 
  private:
   friend class ToastManagerTest;
 
   // Returns the current bounds of the overlay, which is based on visibility.
   gfx::Rect CalculateOverlayBounds();
 
-  // gfx::LayerAnimationObserver overrides:
-  void OnLayerAnimationEnded(ui::LayerAnimationSequence* sequence) override;
-  void OnLayerAnimationAborted(ui::LayerAnimationSequence* sequence) override;
-  void OnLayerAnimationScheduled(ui::LayerAnimationSequence* sequence) override;
+  void OnImplicitAnimationsScheduled() override;
+  void OnImplicitAnimationsCompleted() override;
 
   views::Widget* widget_for_testing();
   void ClickDismissButtonForTesting(const ui::Event& event);
 
-  bool is_visible_ = false;
   Delegate* const delegate_;
   const std::string text_;
   std::unique_ptr<views::Widget> overlay_widget_;
   std::unique_ptr<ToastOverlayView> overlay_view_;
   gfx::Size widget_size_;
 
   DISALLOW_COPY_AND_ASSIGN(ToastOverlay);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_TOAST_TOAST_OVERLAY_H_