Routes calls to WM through WS

components/mus/ws/window_tree_host_impl.h

Index: components/mus/ws/window_tree_host_impl.h
diff --git a/components/mus/ws/window_tree_host_impl.h b/components/mus/ws/window_tree_host_impl.h
index 2da062cd3771002d9fef0e082d8dc70d8e82589c..867d7378f8134b143a7b7da412aa4d26f0c1711b 100644
--- a/components/mus/ws/window_tree_host_impl.h
+++ b/components/mus/ws/window_tree_host_impl.h
@@ -40,7 +40,8 @@ class WindowTreeHostImpl : public DisplayManagerDelegate,
                      ConnectionManager* connection_manager,
                      mojo::ApplicationImpl* app_impl,
                      const scoped_refptr<GpuState>& gpu_state,
-                     const scoped_refptr<SurfacesState>& surfaces_state);
+                     const scoped_refptr<SurfacesState>& surfaces_state,
+                     mojom::WindowManagerPtr window_manater);
   ~WindowTreeHostImpl() override;
 
   // Initializes state that depends on the existence of a WindowTreeHostImpl.
@@ -66,6 +67,8 @@ class WindowTreeHostImpl : public DisplayManagerDelegate,
 
   ConnectionManager* connection_manager() { return connection_manager_; }
 
+  mojom::WindowManager* window_manager() { return window_manager_.get(); }
+
   // Returns the root ServerWindow of this viewport.
   ServerWindow* root_window() { return root_.get(); }
   const ServerWindow* root_window() const { return root_.get(); }
@@ -116,6 +119,7 @@ class WindowTreeHostImpl : public DisplayManagerDelegate,
   scoped_ptr<ServerWindow> root_;
   scoped_ptr<DisplayManager> display_manager_;
   scoped_ptr<FocusController> focus_controller_;
+  mojom::WindowManagerPtr window_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowTreeHostImpl);
 };