Skip mulitple-dispay tests on win8

ash/keyboard_overlay/keyboard_overlay_delegate_unittest.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/keyboard_overlay/keyboard_overlay_delegate.h"
 
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/aura/window.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/screen.h"
 #include "ui/views/widget/widget.h"
 
 namespace ash {
 
 typedef test::AshTestBase KeyboardOverlayDelegateTest;
 
 // Verifies we can show and close the widget for the overlay dialog.
 TEST_F(KeyboardOverlayDelegateTest, ShowAndClose) {
+  if (!SupportsMultipleDisplays())
+    return;
+
   UpdateDisplay("500x400,300x200");
   KeyboardOverlayDelegate delegate(ASCIIToUTF16("Title"),
                                    GURL("chrome://keyboardoverlay/"));
   // Showing the dialog creates a widget.
   views::Widget* widget = delegate.Show(NULL);
   EXPECT_TRUE(widget);
 
   // The widget is on the primary root window.
   EXPECT_EQ(Shell::GetPrimaryRootWindow(),
             widget->GetNativeWindow()->GetRootWindow());
 
   // The widget is horizontally centered at the bottom of the work area.
   gfx::Rect work_area = Shell::GetScreen()->GetPrimaryDisplay().work_area();
   gfx::Rect bounds = widget->GetRestoredBounds();
   EXPECT_EQ(work_area.CenterPoint().x(), bounds.CenterPoint().x());
   EXPECT_EQ(work_area.bottom(), bounds.bottom());
 
   // Clean up.
   widget->CloseNow();
 }
 
 }  // namespace ash