Makes GetRootWindow() public on Window so we can begin to convert uses of RootWindow::GetInstance().

ui/aura/window.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_AURA_WINDOW_H_
 #define UI_AURA_WINDOW_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 87 matching lines @@
   // end of ~Window().
   ui::Layer* AcquireLayer();
 
   WindowDelegate* delegate() { return delegate_; }
 
   const gfx::Rect& bounds() const;
 
   Window* parent() { return parent_; }
   const Window* parent() const { return parent_; }
 
+  // Returns the RootWindow that contains this Window or NULL if the Window is
+  // not contained by a RootWindow.
+  virtual RootWindow* GetRootWindow();
+  virtual const RootWindow* GetRootWindow() const;
+
   // The Window does not own this object.
   void set_user_data(void* user_data) { user_data_ = user_data; }
   void* user_data() const { return user_data_; }
 
   // Changes the visibility of the window.
   void Show();
   void Hide();
   // Returns true if this window and all its ancestors are visible.
   bool IsVisible() const;
 
@@ skipping 164 matching lines @@
   // Fix ViewProp to be able to tell if the property exists and
   // change it to -1.
   void* GetProperty(const char* name) const;
   int GetIntProperty(const char* name) const;
 
   // Returns true if this window is currently stopping event
   // propagation for any windows behind it in the z-order.
   bool StopsEventPropagation() const;
 
  protected:
-  // Returns the root window or NULL if we aren't yet attached to the root
-  // window.
-  virtual RootWindow* GetRootWindow();
-
   // Called when the |window| is being detached from the root window
   // by being removed from its parent. It is called before |parent_| is
   // set to NULL.
   virtual void OnWindowDetachingFromRootWindow(aura::Window* window);
 
   // Called when the |window| is attached to the root window by being added
   // to its parent.
   virtual void OnWindowAttachedToRootWindow(aura::Window* window);
 
  private:
@@ skipping 91 matching lines @@
   // TODO(oshima): Consolidcate ViewProp and aura::window property
   // implementation.
   std::map<const char*, void*> prop_map_;
 
   DISALLOW_COPY_AND_ASSIGN(Window);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_H_