Skip mulitple-dispay tests on win8

ash/display/display_manager.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/display/display_manager.h"
 
 #include <cmath>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 403 matching lines @@
   for (DisplayList::const_iterator iter = displays_.begin();
        iter != displays_.end(); ++iter) {
     display_info_list.push_back(GetDisplayInfo(iter->id()));
   }
   AddMirrorDisplayInfoIfAny(&display_info_list);
   UpdateDisplays(display_info_list);
 }
 
 void DisplayManager::UpdateDisplays(
     const std::vector<DisplayInfo>& updated_display_info_list) {
+#if defined(OS_WIN)
+  if (base::win::GetVersion() >= base::win::VERSION_WIN8) {
+    DCHECK_EQ(1u, updated_display_info_list.size()) <<
+        "Multiple display test does not work on Win8 bots. Please "
+        "skip (don't disable) the test using |SupportMultipleDisplay()|";
+  }
+#endif
+
   DisplayInfoList new_display_info_list = updated_display_info_list;
   std::sort(displays_.begin(), displays_.end(), DisplaySortFunctor());
   std::sort(new_display_info_list.begin(),
             new_display_info_list.end(),
             DisplayInfoSortFunctor());
   DisplayList removed_displays;
   std::vector<size_t> changed_display_indices;
   std::vector<size_t> added_display_indices;
 
   DisplayList::iterator curr_iter = displays_.begin();
@@ skipping 421 matching lines @@
   // always (0,0) and the secondary display's bounds will be updated
   // by |DisplayController::UpdateDisplayBoundsForLayout|.
   new_display.SetScaleAndBounds(
       display_info.device_scale_factor(), gfx::Rect(bounds_in_pixel.size()));
   new_display.set_rotation(display_info.rotation());
   return new_display;
 }
 
 }  // namespace internal
 }  // namespace ash