Make the warning level consistent across the project

Source/core/core_derived_sources.gyp

 #
 # Copyright (C) 2013 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
@@ skipping 77 matching lines @@
           ],
         },
       ]
     },
     {
       'target_name': 'make_core_derived_sources',
       'type': 'none',
       'hard_dependency': 1,
       'dependencies': [
         'generate_test_support_idls',
+        '../config.gyp:config',
       ],
       'sources': [
         # bison rule
         'css/CSSGrammar.y',
         'xml/XPathGrammar.y',
       ],
       'actions': [
         {
           'action_name': 'generateV8ArrayBufferViewCustomScript',
           'inputs': [
@@ skipping 489 matching lines @@
             '<(RULE_INPUT_PATH)',
             '<(SHARED_INTERMEDIATE_DIR)/blink',
             '<(bison_exe)',
           ],
           'msvs_cygwin_shell': 1,
         },
       ],
     },
   ],
 }