Move Screen, its impls, DisplayObserver and DisplayChangeNotifier to ui/display

ui/views/widget/desktop_aura/desktop_factory_ozone.h

 // 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_FACTORY_OZONE_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_FACTORY_OZONE_H_
 
 #include "ui/views/views_export.h"
 
-namespace gfx {
-class Rect;
+namespace display {
 class Screen;
 }
 
-namespace display {
-using Screen = gfx::Screen;
+namespace gfx {
+class Rect;
 }
 
 namespace views {
 class DesktopNativeWidgetAura;
 class DesktopWindowTreeHost;
 
 namespace internal {
 class NativeWidgetDelegate;
 }
 
@@ skipping 18 matching lines @@
   // Ozone implementation.
   virtual display::Screen* CreateDesktopScreen() = 0;
 
  private:
   static DesktopFactoryOzone* impl_; // not owned
 };
 
 }  // namespace views
 
 #endif // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_FACTORY_OZONE_H_