Fix many* python scripts in src/

testing/generate_gmock_mutant.py

-#!/usr/bin/python
-# Copyright (c) 2009 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.
 
 import string
+import sys
 
 HEADER = """\
 // 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.
 
 // This file automatically generated by testing/generate_gmock_mutant.py.
 // DO NOT EDIT.
 
 #ifndef TESTING_GMOCK_MUTANT_H_
@@ skipping 423 matching lines @@
 def main():
   print HEADER
   for prebound in xrange(0, 6 + 1):
     for args in xrange(0, 6 + 1):
       GenerateDispatch(prebound, args)
   print MUTANT
   for prebound in xrange(0, 6 + 1):
     for args in xrange(0, 6 + 1):
       GenerateCreateFunctor(prebound, args)
   print FOOTER
+  return 0
+
 
 if __name__ == "__main__":
-  main()
+  sys.exit(main())