Fix python scripts in src/chrome/

chrome/tools/check_grd_for_unused_strings.py

-#!/usr/bin/python
-
-# Copyright (c) 2010 The Chromium Authors. All rights reserved.
+#!/usr/bin/env python
+# Copyright (c) 2011 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.
 
 """Without any args, this simply loads the IDs out of a bunch of the Chrome GRD
 files, and then checks the subset of the code that loads the strings to try
 and figure out what isn't in use any more.
 You can give paths to GRD files and source directories to control what is
 check instead.
 """
 
@@ skipping 90 matching lines @@
     print 'The following ids are in GRD files, but *appear* to be unused:'
     for file_path, file_ids in file_id_map.iteritems():
       missing = ids_left.intersection(file_ids)
       if len(missing) > 0:
         print '  %s:' % (file_path)
         print '\n'.join('    %s' % (x) for x in sorted(missing))
 
   return 0
 
 
-if __name__ == '__main__':
+def main():
   # script lives in src/chrome/tools
   chrome_tools_dir = os.path.dirname(os.path.abspath(sys.argv[0]))
   src_dir = os.path.dirname(os.path.dirname(chrome_tools_dir))
 
   # Collect the args into the right buckets
   src_dirs = []
   grd_files = []
   for arg in sys.argv[1:]:
     if arg.lower().endswith('.grd'):
       grd_files.append(arg)
@@ skipping 30 matching lines @@
     src_dirs = [
       os.path.join(src_dir, 'app'),
       os.path.join(src_dir, 'content'),
       os.path.join(src_dir, 'chrome'),
       os.path.join(src_dir, 'ui'),
       os.path.join(src_dir, 'views'),
       # nsNSSCertHelper.cpp has a bunch of ids
       os.path.join(src_dir, 'third_party', 'mozilla_security_manager'),
     ]
 
-  sys.exit(CheckForUnusedGrdIDsInSources(grd_files, src_dirs))
+  return CheckForUnusedGrdIDsInSources(grd_files, src_dirs)
+
+
+if __name__ == '__main__':
+  sys.exit(main())