Make the warning level consistent across the project

Source/wtf/wtf.gyp

 # Copyright (C) 2012 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 56 matching lines @@
       },
     },
     {
       'target_name': 'wtf',
       'type': '<(component)',
       'include_dirs': [
         '..',
       ],
       'dependencies': [
           'wtf_config',
+          '../config.gyp:config',
           '<(DEPTH)/third_party/icu/icu.gyp:icui18n',
           '<(DEPTH)/third_party/icu/icu.gyp:icuuc',
       ],
       'sources': [
         '<@(wtf_files)',
       ],
       'defines': [
         'WTF_IMPLEMENTATION=1',
       ],
       'direct_dependent_settings': {
@@ skipping 65 matching lines @@
             ['exclude', 'CF\\.cpp$'],
             ['exclude', 'Mac\\.mm$'],
             # mac is the only OS that uses WebKit's copy of TCMalloc.
             ['exclude', 'TC.*\\.(cpp|h)$'],
           ],
         }],
       ],
     },
   ]
 }