Separate ash::test::DisplayManagerTestApi from ash

ash/screen_util.h

 // Copyright 2014 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 ASH_SCREEN_UTIL_H_
 #define ASH_SCREEN_UTIL_H_
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
 
@@ skipping 32 matching lines @@
   // TODO(oshima): Move following two to wm/coordinate_conversion.h
   // Converts |rect| from |window|'s coordinates to the virtual screen
   // coordinates.
   static gfx::Rect ConvertRectToScreen(aura::Window* window,
                                        const gfx::Rect& rect);
 
   // Converts |rect| from virtual screen coordinates to the |window|'s
   // coordinates.
   static gfx::Rect ConvertRectFromScreen(aura::Window* window,
                                          const gfx::Rect& rect);
-
-  // Returns a display::Display object for secondary display. Returns
-  // invalid display if there is no secondary display connected.
-  static const display::Display& GetSecondaryDisplay();
-
  private:
   ScreenUtil() {}
   ~ScreenUtil() {}
 
   DISALLOW_COPY_AND_ASSIGN(ScreenUtil);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SCREEN_UTIL_H_