Add RootWindowController

ash/wm/screen_dimmer.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 ASH_WM_SCREEN_DIMMER_H_
 #define ASH_WM_SCREEN_DIMMER_H_
 #pragma once
 
 #include "ash/ash_export.h"
 #include "base/basictypes.h"
@@ skipping 29 matching lines @@
 
    private:
     ScreenDimmer* dimmer_;  // not owned
 
     DISALLOW_COPY_AND_ASSIGN(TestApi);
   };
 
   explicit ScreenDimmer(aura::RootWindow* root_window);
   virtual ~ScreenDimmer();
 
-  // Dim or undim the screen.
+  // Dim or undim the root window.
   void SetDimming(bool should_dim);
 
   // aura::RootWindowObserver overrides:
   virtual void OnRootWindowResized(const aura::RootWindow* root,
                                    const gfx::Size& old_size) OVERRIDE;
 
  private:
   friend class TestApi;
 
   aura::RootWindow* root_window_;
 
   // Partially-opaque layer that's stacked above all of the root window's
   // children and used to dim the screen.  NULL until the first time we dim.
   scoped_ptr<ui::Layer> dimming_layer_;
 
   // Are we currently dimming the screen?
   bool currently_dimming_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenDimmer);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_WM_SCREEN_DIMMER_H_