ash: Add RootWindowHostFactory class.

ash/root_window_delegate_win.cc

Index: ash/root_window_delegate_win.cc
diff --git a/ash/root_window_delegate_win.cc b/ash/root_window_delegate_win.cc
new file mode 100644
index 0000000000000000000000000000000000000000..19f8d5d9f66400a97d9cc2bc14e4d0cc4132b7f7
--- /dev/null
+++ b/ash/root_window_delegate_win.cc
@@ -0,0 +1,35 @@
+// 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.
+
+#include "ash/root_window_delegate.h"
+
+#include "ui/aura/remote_root_window_host_win.h"
+#include "ui/aura/root_window_host.h"
+
+namespace {
+
+class RootWindowDelegateImpl : public ash::RootWindowDelegate {
+ public:
+  RootWindowDelegateImpl() {}
+
+  // Overridden from RootWindowDelegate:
+  virtual aura::RootWindowHost* CreateRootWindowHost(
+      const gfx::Rect& initial_bounds) OVERRIDE {
+    if (base::win::GetVersion() >= base::win::VERSION_WIN8) {
+      return aura::RemoteRootWindowHostWin::Create(initial_bounds);
+    }
+    return aura::RootWindowHost::Create(initial_bounds);
+  }
+};
+
+}
+
+namespace ash {
+
+// static
+aura::RootWindowDelegate* RootWindowDelegate::Create() {
+  return new RootWindowDelegateImpl();
+}
+
+}  // namespace ash