views: Make sure the bubble-delegate removes itself from the anchor-widget's observer list.

ui/views/bubble/bubble_delegate.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 UI_VIEWS_BUBBLE_BUBBLE_DELEGATE_H_
 #define UI_VIEWS_BUBBLE_BUBBLE_DELEGATE_H_
 #pragma once
 
 #include "base/gtest_prod_util.h"
 #include "ui/base/animation/animation_delegate.h"
@@ skipping 24 matching lines @@
   BubbleDelegateView(View* anchor_view,
                      BubbleBorder::ArrowLocation arrow_location);
   virtual ~BubbleDelegateView();
 
   // Create and initialize the bubble Widget(s) with proper bounds.
   static Widget* CreateBubble(BubbleDelegateView* bubble_delegate);
 
   // WidgetDelegate overrides:
   virtual View* GetInitiallyFocusedView() OVERRIDE;
   virtual BubbleDelegateView* AsBubbleDelegate() OVERRIDE;
+  virtual void WindowClosing() OVERRIDE;
   virtual View* GetContentsView() OVERRIDE;
   virtual NonClientFrameView* CreateNonClientFrameView(
       views::Widget* widget) OVERRIDE;
 
   // Widget::Observer overrides:
   virtual void OnWidgetClosing(Widget* widget) OVERRIDE;
   virtual void OnWidgetVisibilityChanged(Widget* widget, bool visible) OVERRIDE;
   virtual void OnWidgetActivationChanged(Widget* widget, bool active) OVERRIDE;
   virtual void OnWidgetMoved(Widget* widget) OVERRIDE;
 
@@ skipping 116 matching lines @@
 
   // Parent native window of the bubble.
   gfx::NativeView parent_window_;
 
   DISALLOW_COPY_AND_ASSIGN(BubbleDelegateView);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_BUBBLE_BUBBLE_DELEGATE_H_