Add switch to run ash tests on desktop in windows 8.

ash/ash_switches.cc

 // 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.
 
 #include "ash/ash_switches.h"
 
 namespace ash {
 namespace switches {
 
 // Enables an animated transition from the boot splash screen (Chrome logo on a
@@ skipping 99 matching lines @@
 
 // Enables the heads-up display for tracking touch points.
 const char kAshTouchHud[] = "ash-touch-hud";
 
 // (Most) Chrome OS hardware reports ACPI power button releases correctly.
 // Standard hardware reports releases immediately after presses.  If set, we
 // lock the screen or shutdown the system immediately in response to a press
 // instead of displaying an interactive animation.
 const char kAuraLegacyPowerButton[] = "aura-legacy-power-button";
 
+#if defined(OS_WIN)
+// Force Ash to open its root window on the desktop, even on Windows 8 where
+// it would normally end up in metro.
+const char kForceAshToDesktop[] = "ash-force-desktop";
+;
+#endif
+
 }  // namespace switches
 }  // namespace ash