Fix python scripts in src/chrome/

chrome/tools/extract_actions.py

-#!/usr/bin/python
+#!/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.
 
 """Extract UserMetrics "actions" strings from the Chrome source.
 
 This program generates the list of known actions we expect to see in the
 user behavior logs.  It walks the Chrome source, looking for calls to
 UserMetrics functions, extracting actions and warning on improper calls,
 as well as generating the lists of possible actions in situations where
@@ skipping 420 matching lines @@
   for action in sorted(actions):
     if hash_output:
       hash = hashlib.md5()
       hash.update(action)
       print >>f, '0x%s\t%s' % (hash.hexdigest()[:16], action)
     else:
       print action
 
   if hash_output:
     print "Done. Do not forget to add chromeactions.txt to your changelist"
+  return 0
+
 
 if '__main__' == __name__:
-  main(sys.argv)
+  sys.exit(main(sys.argv))