Add GetDisplayWithDisplayId to display::Screen.

ash/test/ash_test_base.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 ASH_TEST_ASH_TEST_BASE_H_
 #define ASH_TEST_ASH_TEST_BASE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 66 matching lines @@
   // Returns the WmShelf for the primary display.
   static WmShelf* GetPrimaryShelf();
 
   // Returns the system tray on the primary display.
   static SystemTray* GetPrimarySystemTray();
 
   // Update the display configuration as given in |display_specs|.
   // See ash::test::DisplayManagerTestApi::UpdateDisplay for more details.
   void UpdateDisplay(const std::string& display_specs);
 
+  // Set the 1st display as an internal display and returns the display Id for
+  // the internal display.
+  // See ash::test::DisplayManagerTestApi::SetFirstDisplayAsInternalDisplay for
+  // more details.
+  int64_t SetFirstDisplayAsInternalDisplay();
+
   // Returns a root Window. Usually this is the active root Window, but that
   // method can return NULL sometimes, and in those cases, we fall back on the
   // primary root Window.
   aura::Window* CurrentContext();
 
   // Creates and shows a widget. See ash/public/cpp/shell_window_ids.h for
   // values for |container_id|.
   static std::unique_ptr<views::Widget> CreateTestWidget(
       views::WidgetDelegate* delegate,
       int container_id,
@@ skipping 112 matching lines @@
   ~NoSessionAshTestBase() override {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NoSessionAshTestBase);
 };
 
 }  // namespace test
 }  // namespace ash
 
 #endif  // ASH_TEST_ASH_TEST_BASE_H_