ash: Add RootWindowHostFactory class.

ash/display/display_manager_delegate.h

Index: ash/display/display_manager_delegate.h
diff --git a/ash/display/display_manager_delegate.h b/ash/display/display_manager_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..3bbbe34a7125b5f26c3d181d67f53801dc44d755
--- /dev/null
+++ b/ash/display/display_manager_delegate.h
@@ -0,0 +1,28 @@
+// 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_DISPLAY_DISPLAY_MANAGER_DELEGATE_H_
+#define ASH_DISPLAY_DISPLAY_MANAGER_DELEGATE_H_
+
+namespace aura {
+class RootWindowDelegate;
+}
+
+namespace ash {
+namespace internal {
+
+// Delegate of the DisplayManager.
+class DisplayManagerDelegate {
+ public:
+  virtual ~DisplayManagerDelegate() {}
+
+  // Creates a new RootWindowDelegate. DisplayManager takes ownership
+  // of the returned value.
+  virtual aura::RootWindowDelegate* CreateRootWindowDelegate() = 0;
+};
+
+}  // namespace internal
+}  // namespace ash
+
+#endif  // ASH_DISPLAY_DISPLAY_MANAGER_DELEGATE_H_