content: Remove views dependency.

ui/views/mus/native_widget_mus.h

 // Copyright 2015 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_MUS_NATIVE_WIDGET_MUS_H_
 #define UI_VIEWS_MUS_NATIVE_WIDGET_MUS_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 25 matching lines @@
 class Window;
 class WindowTreeClient;
 namespace mojom {
 enum class Cursor;
 enum class EventResult;
 }
 }
 
 namespace ui {
 class Event;
+class ViewProp;
 }
 
 namespace wm {
 class CursorManager;
 class FocusController;
 }
 
 namespace views {
 class SurfaceContextFactory;
 class WidgetDelegate;
@@ skipping 209 matching lines @@
 
   // Aura configuration.
   std::unique_ptr<SurfaceContextFactory> context_factory_;
   std::unique_ptr<WindowTreeHostMus> window_tree_host_;
   aura::Window* content_;
   std::unique_ptr<wm::FocusController> focus_client_;
   std::unique_ptr<MusCaptureClient> capture_client_;
   std::unique_ptr<aura::client::WindowTreeClient> window_tree_client_;
   std::unique_ptr<aura::client::ScreenPositionClient> screen_position_client_;
   std::unique_ptr<wm::CursorManager> cursor_manager_;
+  std::unique_ptr<ui::ViewProp> prop_;
 
   base::WeakPtrFactory<NativeWidgetMus> close_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeWidgetMus);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_MUS_NATIVE_WIDGET_MUS_H_