Add window manager component.

wm/host/root_window_host_factory.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright (c) 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.
 
-#include "ash/host/root_window_host_factory.h"
+#include "wm/host/root_window_host_factory.h"
 
 #include "ui/aura/root_window_host.h"
 
+namespace wm {
+
 namespace {
 
-class RootWindowHostFactoryImpl : public ash::RootWindowHostFactory {
+class RootWindowHostFactoryImpl : public RootWindowHostFactory {
  public:
-  RootWindowHostFactoryImpl() {}
+  RootWindowHostFactoryImpl() {
+    impl_.reset(ash::RootWindowHostFactory::Create());
+  }
 
   // Overridden from RootWindowHostFactory:
   virtual aura::RootWindowHost* CreateRootWindowHost(
       const gfx::Rect& initial_bounds) OVERRIDE {
-    return aura::RootWindowHost::Create(initial_bounds);
+    return impl_->CreateRootWindowHost(initial_bounds);
   }
+
+  scoped_ptr<ash::RootWindowHostFactory> impl_;
 };
 
-}
-
-namespace ash {
+}  // namespace
 
 // static
 RootWindowHostFactory* RootWindowHostFactory::Create() {
   return new RootWindowHostFactoryImpl;
 }
 
-}  // namespace ash
+}  // namespace wm