Rename RootViewManager to DisplayManager

mojo/services/view_manager/root_view_manager_delegate.h

-// Copyright 2014 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 MOJO_SERVICES_VIEW_MANAGER_ROOT_VIEW_MANAGER_DELEGATE_H_
-#define MOJO_SERVICES_VIEW_MANAGER_ROOT_VIEW_MANAGER_DELEGATE_H_
-
-#include "mojo/services/view_manager/view_manager_export.h"
-
-namespace mojo {
-namespace service {
-
-class MOJO_VIEW_MANAGER_EXPORT RootViewManagerDelegate {
- public:
-  // Invoked when the WindowTreeHost is ready.
-  virtual void OnRootViewManagerWindowTreeHostCreated() = 0;
-
- protected:
-  virtual ~RootViewManagerDelegate() {}
-};
-
-}  // namespace service
-}  // namespace mojo
-
-#endif  // MOJO_SERVICES_VIEW_MANAGER_ROOT_VIEW_MANAGER_H_