Add OnDisplayMetricsChanged in DisplayObserver.

ash/wm/overview/window_overview.h

 // Copyright 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 ASH_WM_OVERVIEW_WINDOW_OVERVIEW_H_
 #define ASH_WM_OVERVIEW_WINDOW_OVERVIEW_H_
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
@@ skipping 49 matching lines @@
   // Moves the overview to only |root_window|.
   void MoveToSingleRootWindow(aura::Window* root_window);
 
   // ui::EventHandler:
   virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE;
   virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
   virtual void OnScrollEvent(ui::ScrollEvent* event) OVERRIDE;
   virtual void OnTouchEvent(ui::TouchEvent* event) OVERRIDE;
 
   // gfx::DisplayObserver:
-  virtual void OnDisplayBoundsChanged(const gfx::Display& display) OVERRIDE;
   virtual void OnDisplayAdded(const gfx::Display& display) OVERRIDE;
   virtual void OnDisplayRemoved(const gfx::Display& display) OVERRIDE;
+  virtual void OnDisplayMetricsChanged(const gfx::Display& display,
+      DisplayObserver::DisplayMetrics metrics) OVERRIDE;
 
  private:
   // Returns the target of |event| or NULL if the event is not targeted at
   // any of the windows in the selector.
   aura::Window* GetEventTarget(ui::LocatedEvent* event);
 
   // Returns the top-level window selected by targeting |window| or NULL if
   // no overview window was found for |window|.
   aura::Window* GetTargetedWindow(aura::Window* window);
 
@@ skipping 44 matching lines @@
   // Tracks windows which were hidden because they were not part of the
   // overview.
   aura::WindowTracker hidden_windows_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowOverview);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_OVERVIEW_WINDOW_OVERVIEW_H_