Fix crash under ExclusiveAccessBubbleViews::AnimationProgressed().

chrome/browser/ui/views/exclusive_access_bubble_views.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 CHROME_BROWSER_UI_VIEWS_EXCLUSIVE_ACCESS_BUBBLE_VIEWS_H_
 #define CHROME_BROWSER_UI_VIEWS_EXCLUSIVE_ACCESS_BUBBLE_VIEWS_H_
 
 #include <memory>
 
 #include "base/compiler_specific.h"
@@ skipping 43 matching lines @@
   void UpdateMouseWatcher();
 
   // Updates |popup|'s bounds given |animation_| and |animated_attribute_|.
   void UpdateBounds();
 
   void UpdateViewContent(ExclusiveAccessBubbleType bubble_type);
 
   // Returns the root view containing |browser_view_|.
   views::View* GetBrowserRootView() const;
 
-  // ExclusiveAccessBubble overrides:
+  // ExclusiveAccessBubble:
   void AnimationProgressed(const gfx::Animation* animation) override;
   void AnimationEnded(const gfx::Animation* animation) override;
   gfx::Rect GetPopupRect(bool ignore_animation_state) const override;
   gfx::Point GetCursorScreenPoint() override;
   bool WindowContainsPoint(gfx::Point pos) override;
   bool IsWindowActive() override;
   void Hide() override;
   void Show() override;
   bool IsAnimating() override;
   bool CanMouseTriggerSlideIn() const override;
 
-  // content::NotificationObserver override:
+  // content::NotificationObserver:
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override;
 
-  // views::WidgetObserver override:
+  // views::WidgetObserver:
+  void OnWidgetDestroyed(views::Widget* widget) override;
   void OnWidgetVisibilityChanged(views::Widget* widget, bool visible) override;
 
   // views::LinkListener override:
   void LinkClicked(views::Link* source, int event_flags) override;
 
   ExclusiveAccessBubbleViewsContext* const bubble_view_context_;
 
   views::Widget* popup_;
 
   // Animation controlling showing/hiding of the exit bubble.
   std::unique_ptr<gfx::SlideAnimation> animation_;
 
   // The contents of the popup.
   SubtleNotificationView* view_;
   base::string16 browser_fullscreen_exit_accelerator_;
 
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(ExclusiveAccessBubbleViews);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_EXCLUSIVE_ACCESS_BUBBLE_VIEWS_H_