Add comments setting emacs and vim tab width and expansion variables....

app/app.gyp

 # Copyright (c) 2009 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.
 
 {
   'variables': {
     # TODO: remove this helper when we have loops in GYP
     'apply_locales_cmd': ['python', '../chrome/tools/build/apply_locales.py',],
     'chromium_code': 1,
   },
@@ skipping 371 matching lines @@
                 'process_outputs_as_sources': 1,
                 'message': 'Generating appid information in <(SHARED_INTERMEDIATE_DIR)/chrome/appid.h'
               },
             ],
           },
         ],
       ],
     },
   ],
 }
+
+# Local Variables:
+# tab-width:2
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=2 shiftwidth=2: