Remove DisplayChangeObserver ash dependencies.

ui/display/manager/display_manager.h

 // Copyright (c) 2012 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_DISPLAY_MANAGER_DISPLAY_MANAGER_H_
 #define UI_DISPLAY_MANAGER_DISPLAY_MANAGER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
+#include <map>
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
@@ skipping 46 matching lines @@
     // Called before and after the display configuration changes.  When
     // |clear_focus| is true, the implementation should deactivate the active
     // window and set the focus window to NULL.
     virtual void PreDisplayConfigurationChange(bool clear_focus) = 0;
     virtual void PostDisplayConfigurationChange(bool must_clear_window) = 0;
 
 #if defined(OS_CHROMEOS)
     // Get the ui::DisplayConfigurator.
     virtual ui::DisplayConfigurator* display_configurator() = 0;
 #endif
-
-    virtual std::string GetInternalDisplayNameString() = 0;
-    virtual std::string GetUnknownDisplayNameString() = 0;
   };
 
   // How the second display will be used.
   // 1) EXTENDED mode extends the desktop to the second dislpay.
   // 2) MIRRORING mode copies the content of the primary display to
   //    the 2nd display. (Software Mirroring).
   // 3) UNIFIED mode creates single desktop across multiple displays.
   enum MultiDisplayMode {
     EXTENDED = 0,
     MIRRORING,
@@ skipping 368 matching lines @@
   base::ObserverList<DisplayObserver> observers_;
 
   base::WeakPtrFactory<DisplayManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DisplayManager);
 };
 
 }  // namespace display
 
 #endif  // UI_DISPLAY_MANAGER_DISPLAY_MANAGER_H_