[ash-md] Animates overview shield in and out

ash/common/wm/overview/window_selector.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_COMMON_WM_OVERVIEW_WINDOW_SELECTOR_H_
 #define ASH_COMMON_WM_OVERVIEW_WINDOW_SELECTOR_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 49 matching lines @@
 
   // Called when the last window selector item from a grid is deleted.
   void OnGridEmpty(WindowGrid* grid);
 
   // Activates |window|.
   void SelectWindow(WmWindow* window);
 
   // Called when |window| is about to get closed.
   void WindowClosing(WindowSelectorItem* window);
 
+  WindowSelectorDelegate* delegate() { return delegate_; }
+
   bool restoring_minimized_windows() const {
     return restoring_minimized_windows_;
   }
 
   int text_filter_bottom() { return text_filter_bottom_; }
 
   // display::DisplayObserver:
   void OnDisplayAdded(const display::Display& display) override;
   void OnDisplayRemoved(const display::Display& display) override;
   void OnDisplayMetricsChanged(const display::Display& display,
@@ skipping 98 matching lines @@
   // The distance between the top edge of the screen and the bottom edge of
   // the text filtering textfield.
   int text_filter_bottom_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowSelector);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_WM_OVERVIEW_WINDOW_SELECTOR_H_