Move root_window_host* in aura to window_tree_host*.

ui/views/widget/desktop_aura/desktop_root_window_host_observer_x11.h

Index: ui/views/widget/desktop_aura/desktop_root_window_host_observer_x11.h
diff --git a/ui/views/widget/desktop_aura/desktop_root_window_host_observer_x11.h b/ui/views/widget/desktop_aura/desktop_root_window_host_observer_x11.h
deleted file mode 100644
index c8e8a48c07d40f896a2df34c25d0536d6ac7dabd..0000000000000000000000000000000000000000
--- a/ui/views/widget/desktop_aura/desktop_root_window_host_observer_x11.h
+++ /dev/null
@@ -1,29 +0,0 @@
-// Copyright 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.
-
-#ifndef UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_OBSERVER_X11_H_
-#define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_OBSERVER_X11_H_
-
-#include "ui/views/views_export.h"
-
-namespace views {
-
-// Allows for the observation of lower level window events.
-class VIEWS_EXPORT DesktopWindowTreeHostObserverX11 {
- public:
-  virtual ~DesktopWindowTreeHostObserverX11() {}
-
-  // Called after we receive a MapNotify event (the X11 server has allocated
-  // resources for it).
-  virtual void OnWindowMapped(unsigned long xid) = 0;
-
-  // Called after we receive an UnmapNotify event (the X11 server has freed
-  // resources for it).
-  virtual void OnWindowUnmapped(unsigned long xid) = 0;
-};
-
-}  // namespace views
-
-#endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_OBSERVER_X11_H_
-