Refactor Mus demo to prepare support for multiple external windows

services/ui/demo/mus_demo.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 SERVICES_UI_DEMO_MUS_DEMO_H_
 #define SERVICES_UI_DEMO_MUS_DEMO_H_
 
 #include <map>
 #include <memory>
 #include <set>
@@ skipping 10 matching lines @@
 
 namespace aura {
 class Env;
 class PropertyConverter;
 
 namespace client {
 class DefaultCaptureClient;
 }
 }  // namespace aura
 
-namespace aura_extra {
-class ImageWindowDelegate;
-}
-
 namespace wm {
 class WMState;
 }
 
 namespace ui {
 namespace demo {
 
 // A simple MUS Demo service. This service connects to the service:ui, adds a
 // new window to the root Window, and draws a spinning square in the center of
 // the window. Provides a simple way to demonstrate that the graphic stack works
@@ skipping 46 matching lines @@
                            const gfx::Point& cursor_location,
                            const base::Callback<void(bool)>& on_done) override;
   void OnWmCancelMoveLoop(aura::Window* window) override;
   void OnWmSetClientArea(
       aura::Window* window,
       const gfx::Insets& insets,
       const std::vector<gfx::Rect>& additional_client_areas) override;
   bool IsWindowActive(aura::Window* window) override;
   void OnWmDeactivateWindow(aura::Window* window) override;
 
-  // Draws one frame, incrementing the rotation angle.
-  void DrawFrame();
-
-  aura::Window* root_window_ = nullptr;
   std::unique_ptr<aura::WindowTreeClient> window_tree_client_;
-  std::unique_ptr<aura::WindowTreeHostMus> window_tree_host_;
   std::unique_ptr<aura::Env> env_;
   std::unique_ptr<display::ScreenBase> screen_;
 
   std::unique_ptr<aura::client::DefaultCaptureClient> capture_client_;
   std::unique_ptr<::wm::WMState> wm_state_;
   std::unique_ptr<aura::PropertyConverter> property_converter_;
 
-  // Window to which we draw the bitmap.
-  std::unique_ptr<aura::Window> bitmap_window_;
-
-  // Destroys itself when the window gets destroyed.
-  aura_extra::ImageWindowDelegate* window_delegate_ = nullptr;
-
-  // Timer for calling DrawFrame().
-  base::RepeatingTimer timer_;
-
-  // Current rotation angle for drawing.
-  double angle_ = 0.0;
-
-  // Last time a frame was drawn.
-  base::TimeTicks last_draw_frame_time_;
+  class WindowTreeData;
+  std::unique_ptr<WindowTreeData> window_tree_data_;
 
   DISALLOW_COPY_AND_ASSIGN(MusDemo);
 };
 
 }  // namespace demo
 }  // namespace aura
 
 #endif  // SERVICES_UI_DEMO_MUS_DEMO_H_