Gets chrome --mus some what working

ui/aura/mus/window_manager_delegate.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_AURA_MUS_WINDOW_MANAGER_DELEGATE_H_
 #define UI_AURA_MUS_WINDOW_MANAGER_DELEGATE_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 45 matching lines @@
   virtual void RemoveActivationParent(Window* window) = 0;
   virtual void ActivateNextWindow() = 0;
   virtual void SetExtendedHitArea(Window* window,
                                   const gfx::Insets& hit_area) = 0;
 
   // Requests the client embedded in |window| to close the window. Only
   // applicable to top-level windows. If a client is not embedded in |window|,
   // this does nothing.
   virtual void RequestClose(Window* window) = 0;
 
+  // Blocks until the initial displays have been received.
+  virtual bool WaitForInitialDisplays() = 0;
+
  protected:
   virtual ~WindowManagerClient() {}
 };
 
 // Used by clients implementing a window manager.
 // TODO(sky): this should be called WindowManager, but that's rather confusing
 // currently.
 class AURA_EXPORT WindowManagerDelegate {
  public:
   // Called once to give the delegate access to functions only exposed to
@@ skipping 107 matching lines @@
   // window.
   virtual void OnWmDeactivateWindow(Window* window) = 0;
 
  protected:
   virtual ~WindowManagerDelegate() {}
 };
 
 }  // namespace ui
 
 #endif  // UI_AURA_MUS_WINDOW_MANAGER_DELEGATE_H_