Move ShowState-related code from PlatformWindowMus to NativeWidgetMus

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 190 matching lines @@
   void OnMouseEvent(ui::MouseEvent* event) override;
   void OnScrollEvent(ui::ScrollEvent* event) override;
   void OnGestureEvent(ui::GestureEvent* event) override;
 
   // Overridden from aura::WindowTreeHostObserver:
   void OnHostCloseRequested(const aura::WindowTreeHost* host) override;
 
  private:
   class MusWindowObserver;
 
+  void SetShowState(mus::mojom::ShowState show_state);
+
   void OnMusWindowVisibilityChanging(mus::Window* window);
   void OnMusWindowVisibilityChanged(mus::Window* window);
 
   mus::Window* window_;
 
   internal::NativeWidgetDelegate* native_widget_delegate_;
 
   const mus::mojom::SurfaceType surface_type_;
   ui::PlatformWindowState show_state_before_fullscreen_;
 
@@ skipping 14 matching lines @@
   std::unique_ptr<aura::client::ScreenPositionClient> screen_position_client_;
   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_