Helpful message for not checking SupportsMultipleDisplays on Win7 tests.

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 614 matching lines @@
        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 SupportsMultipleDisplays()";
-  }
+  DCHECK_EQ(1u, updated_display_info_list.size()) <<
+      ": Multiple display test does not work on Windows bots. Please "
+      "skip (don't disable) the test using SupportsMultipleDisplays()";
 #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;
@@ skipping 467 matching lines @@
       new_secondary_origin.Offset(-secondary_bounds.width(), offset);
       break;
   }
   gfx::Insets insets = secondary_display->GetWorkAreaInsets();
   secondary_display->set_bounds(
       gfx::Rect(new_secondary_origin, secondary_bounds.size()));
   secondary_display->UpdateWorkAreaFromInsets(insets);
 }
 
 }  // namespace ash