Fix python scripts in src/chrome/

chrome/tools/build/generate_policy_source.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.
 
 '''python %prog [options] platform chromium_os_flag template
 
 platform specifies which platform source is being generated for
   and can be one of (win, mac, linux)
 chromium_os_flag should be 1 if this is a Chromium OS build
 template is the path to a .json policy template file.'''
@@ skipping 32 matching lines @@
                     metavar="FILE");
   parser.add_option("--ppd", "--protobuf-decoder", dest="decoder_path",
                     help="generate C++ code decoding the policy protobuf",
                     metavar="FILE");
 
   (opts, args) = parser.parse_args();
 
   if len(args) != 3:
     print "exactly platform, chromium_os flag and input file must be specified."
     parser.print_help()
-    sys.exit(2)
+    return 2
   template_file_contents = _LoadJSONFile(args[2]);
   if opts.header_path is not None:
     _WritePolicyConstantHeader(template_file_contents, args, opts);
   if opts.source_path is not None:
     _WritePolicyConstantSource(template_file_contents, args, opts);
   if opts.type_path is not None:
     _WritePolicyTypeEnumerationHeader(template_file_contents, args, opts);
   if opts.proto_path is not None:
     _WriteProtobuf(template_file_contents, args, opts.proto_path)
   if opts.decoder_path is not None:
     _WriteProtobufParser(template_file_contents, args, opts.decoder_path)
+  return 0
 
 
 #------------------ shared helpers ---------------------------------#
 def _OutputGeneratedWarningForC(f, template_file_path):
     f.write('//\n'
             '// DO NOT MODIFY THIS FILE DIRECTLY!\n'
             '// IT IS GENERATED BY generate_policy_source.py\n'
             '// FROM ' + template_file_path + '\n'
             '//\n\n')
 
@@ skipping 379 matching lines @@
     f.write(CPP_HEAD)
     for policy in template_file_contents['policy_definitions']:
       if policy['type'] == 'group':
         for sub_policy in policy['policies']:
           _WritePolicyCode(f, sub_policy)
       else:
         _WritePolicyCode(f, policy)
     f.write(CPP_FOOT)
 
 
-#------------------ main() -----------------------------------------#
 if __name__ == '__main__':
-  main();
+  sys.exit(main())