Adds Window::MoveChildToFront, with surrounding changes.

ui/aura/window.h

 // Copyright (c) 2011 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 <vector>
@@ skipping 132 matching lines @@
   // Sets the contents of the window.
   void SetCanvas(const SkCanvas& canvas, const gfx::Point& origin);
 
   // Sets the parent window of the window. If NULL, the window is parented to
   // the desktop's window.
   void SetParent(Window* parent);
 
   // Move the specified child of this Window to the front of the z-order.
   void MoveChildToFront(Window* child);
 
+  // Moves |other| to be above |child|. Does nothing if |child| is already above
+  // |other|.
+  void MoveChildAbove(Window* child, Window* other);
+
   // Returns true if this window can be activated.
   bool CanActivate() const;
 
   // Tree operations.
   // TODO(beng): Child windows are currently not owned by the hierarchy. We
   //             should change this.
   void AddChild(Window* child);
   void RemoveChild(Window* child);
 
   const Windows& children() const { return children_; }
@@ skipping 186 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_