Separate ash::test::DisplayManagerTestApi from ash

ash/system/toast/toast_manager_unittest.cc

 // Copyright 2016 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.
 
 #include "ash/common/shelf/shelf_constants.h"
 #include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/system/toast/toast_manager.h"
 #include "ash/common/wm/wm_screen_util.h"
 #include "ash/common/wm_shell.h"
 #include "ash/display/display_manager.h"
-#include "ash/screen_util.h"
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "base/run_loop.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/compositor/scoped_animation_duration_scale_mode.h"
 #include "ui/views/widget/widget.h"
 
 namespace ash {
@@ skipping 262 matching lines @@
   EXPECT_EQ(base::ASCIIToUTF16("TEXT3"), GetCurrentText());
   // Cancel the shown toast.
   CancelToast(id3);
   // Confirm that the shown toast disappears.
   EXPECT_FALSE(GetCurrentOverlay());
   // Confirm that only 1 toast is shown.
   EXPECT_EQ(2, GetToastSerial());
 }
 
 }  // namespace ash