Converts WindowTreeClientTest to be in terms of aura

ui/views/mus/desktop_window_tree_host_mus.h

 // Copyright 2016 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_WINDOW_TREE_HOST_MUS_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_
 
 #include <memory>
 #include <set>
 
@@ skipping 16 matching lines @@
       public MusClientObserver,
       public aura::WindowTreeHostMus,
       public aura::EnvObserver {
  public:
   DesktopWindowTreeHostMus(
       internal::NativeWidgetDelegate* native_widget_delegate,
       DesktopNativeWidgetAura* desktop_native_widget_aura,
       const std::map<std::string, std::vector<uint8_t>>* mus_properties);
   ~DesktopWindowTreeHostMus() override;
 
+  // Called when the window was deleted on the server.
+  void ServerDestroyedWindow() { CloseNow(); }
+
  private:
   bool IsDocked() const;
 
   void SendClientAreaToServer();
   void SendHitTestMaskToServer();
 
   // Helper function to get the scale factor.
   float GetScaleFactor() const;
 
   void SetBoundsInDIP(const gfx::Rect& bounds_in_dip);
@@ skipping 93 matching lines @@
 
   // Used so that Close() isn't immediate.
   base::WeakPtrFactory<DesktopWindowTreeHostMus> close_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopWindowTreeHostMus);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_