WIP: Propagate SurfaceID up window tree hierarchy

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 76 matching lines @@
 
   ui::mojom::SurfaceType surface_type() const { return surface_type_; }
   ui::Window* window() { return window_; }
   WindowTreeHostMus* window_tree_host() { return window_tree_host_.get(); }
 
   aura::Window* GetRootWindow();
 
   void OnPlatformWindowClosed();
   void OnActivationChanged(bool active);
 
- protected:
+ public:
   // Updates the client area in the ui::Window.
   virtual void UpdateClientArea();
 
   // internal::NativeWidgetPrivate:
   NonClientFrameView* CreateNonClientFrameView() override;
   void InitNativeWidget(const Widget::InitParams& params) override;
   void OnWidgetInitDone() override;
   bool ShouldUseNativeFrame() const override;
   bool ShouldWindowContentsBeTransparent() const override;
   void FrameTypeChanged() override;
@@ skipping 174 matching lines @@
   std::unique_ptr<wm::CursorManager> cursor_manager_;
 
   base::WeakPtrFactory<NativeWidgetMus> close_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeWidgetMus);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_MUS_NATIVE_WIDGET_MUS_H_