chromeos: Remove AshTestBase::SupportsMultipleDisplays

ash/drag_drop/drag_drop_interactive_uitest.cc

 // Copyright (c) 2013 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/drag_drop/drag_drop_controller.h"
 
 #include "ash/shell.h"
 #include "ash/test/ash_interactive_ui_test_base.h"
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 98 matching lines @@
       base::Bind(&DragDropAcrossMultiDisplay_Step2));
 }
 
 }  // namespace
 
 using DragDropTest = test::AshInteractiveUITestBase;
 
 // Test if the mouse gets moved properly to another display
 // during drag & drop operation.
 TEST_F(DragDropTest, DragDropAcrossMultiDisplay) {
-  if (!SupportsMultipleDisplays())
-    return;
-
   UpdateDisplay("400x400,400x400");
   aura::Window::Windows root_windows =
       Shell::GetInstance()->GetAllRootWindows();
   views::View* draggable_view = new DraggableView();
   draggable_view->set_drag_controller(NULL);
   draggable_view->SetBounds(0, 0, 100, 100);
   views::Widget* source =
       CreateWidget(draggable_view, gfx::Rect(0, 0, 100, 100));
 
   TargetView* target_view = new TargetView();
@@ skipping 10 matching lines @@
 
   base::RunLoop().Run();
 
   EXPECT_TRUE(target_view->dropped());
 
   source->Close();
   target->Close();
 }
 
 }  // namespace ash