Emit warning when touchscreen association fails.

ash/touch/touchscreen_util.cc

 // Copyright 2014 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/touch/touchscreen_util.h"
 
 #include <set>
 
 #include "base/files/file_util.h"
 #include "base/logging.h"
@@ skipping 256 matching lines @@
             << " (size: " << device->size.ToString()
             << ", sys_path: " << device->sys_path.LossyDisplayName() << ")";
   }
 
   AssociateInternalDevices(&displays, &devices);
   AssociateUdlDevices(&displays, &devices);
   AssociateSameSizeDevices(&displays, &devices);
   AssociateToSingleDisplay(&displays, &devices);
 
   for (const DisplayInfo* display : displays)
-    VLOG(1) << "Unmatched display " << display->name();
+    LOG(WARNING) << "Unmatched display " << display->name();
   for (const ui::TouchscreenDevice* device : devices)
-    VLOG(1) << "Unmatched device " << device->name;
+    LOG(WARNING) << "Unmatched device " << device->name;
 }
 
 }  // namespace ash