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

sandbox/sandbox.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.
 
 {
   'conditions': [
     [ 'OS=="linux" and selinux==0', {
       'targets': [
         {
           'target_name': 'chrome_sandbox',
@@ skipping 318 matching lines @@
             'POCDLL_EXPORTS',
           ],
           'include_dirs': [
             '..',
           ],
         },
       ],
     }],
   ],
 }
+
+# Local Variables:
+# tab-width:2
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=2 shiftwidth=2: