Revert of chromeos: Makes mushrome use simplified display management

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 47 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, or if displays are
-  // not automatically created until the connection to mus has been
-  // established.
+  // Blocks until the initial displays have been received.
   virtual bool WaitForInitialDisplays() = 0;
 
   // Used by the window manager to create a new display. This is only useful if
   // the WindowTreeClient was configured not to automatically create displays
   // (see ConnectAsWindowManager()). The caller needs to configure
   // DisplayInitParams on the returned object.
   virtual WindowTreeHostMusInitParams CreateInitParamsForNewDisplay() = 0;
 
  protected:
   virtual ~WindowManagerClient() {}
@@ skipping 114 matching lines @@
   // window.
   virtual void OnWmDeactivateWindow(Window* window) = 0;
 
  protected:
   virtual ~WindowManagerDelegate() {}
 };
 
 }  // namespace ui
 
 #endif  // UI_AURA_MUS_WINDOW_MANAGER_DELEGATE_H_