Add OnDisplayMetricsChanged in DisplayObserver.

ui/message_center/views/message_popup_collection.h

 // Copyright (c) 2013 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_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_COLLECTION_H_
 #define UI_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_COLLECTION_H_
 
 #include <list>
 #include <map>
 
@@ skipping 93 matching lines @@
   // Runs the next step in update/animate sequence, if the defer counter is not
   // zero. Otherwise, simply waits when it becomes zero.
   void DoUpdateIfPossible();
 
   // Removes the toast from our internal list of toasts; this is called when the
   // toast is irrevocably closed (such as within RemoveToast).
   void ForgetToast(ToastContentsView* toast);
 
   // Updates |work_area_| and re-calculates the alignment of notification toasts
   // rearranging them if necessary.
-  // This is separated from methods from OnDisplayBoundsChanged(), since
+  // This is separated from methods from OnDisplayMetricsChanged(), since
   // sometimes the display info has to be specified directly. One example is
   // shelf's auto-hide change. When the shelf in ChromeOS is temporarily shown
   // from auto hide status, it doesn't change the display's work area but the
   // actual work area for toasts should be resized.
   void SetDisplayInfo(const gfx::Rect& work_area,
                       const gfx::Rect& screen_bounds);
 
   // Overridden from gfx::DislayObserver:
-  virtual void OnDisplayBoundsChanged(const gfx::Display& display) OVERRIDE;
   virtual void OnDisplayAdded(const gfx::Display& new_display) OVERRIDE;
   virtual void OnDisplayRemoved(const gfx::Display& old_display) OVERRIDE;
+  virtual void OnDisplayMetricsChanged(const gfx::Display& display,
+                                       uint32_t metrics) OVERRIDE;
 
   // Used by ToastContentsView to locate itself.
   gfx::NativeView parent() const { return parent_; }
 
  private:
   FRIEND_TEST_ALL_PREFIXES(ash::WebNotificationTrayTest,
                            ManyPopupNotifications);
   friend class test::MessagePopupCollectionTest;
   friend class ash::WebNotificationTrayTest;
   typedef std::list<ToastContentsView*> Toasts;
@@ skipping 86 matching lines @@
   // Gives out weak pointers to toast contents views which have an unrelated
   // lifetime.  Must remain the last member variable.
   base::WeakPtrFactory<MessagePopupCollection> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MessagePopupCollection);
 };
 
 }  // namespace message_center
 
 #endif // UI_MESSAGE_CENTER_VIEWS_MESSAGE_POPUP_COLLECTION_H_