Fixing flag.

download_firefox_nightly.py

 #!/usr/bin/env python
 # Copyright 2013 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.
 
 """Downloads a Firefox Nightly build for the current platform."""
 
 import datetime
 import glob
 import os
@@ skipping 121 matching lines @@
 
 def main():
   usage = 'usage: %prog -t <target_dir>'
   parser = OptionParser(usage)
   parser.add_option('-t', '--target-dir',
                     help=('Target directory to put the downloaded and extracted'
                           ' folder with the Firefox Nightly build in.'))
   parser.add_option('-f', '--force', action='store_true',
                     help=('Force download even if the current nightly is '
                           'already downloaded.'))
-  parser.add_option('-c', '--clean-old-archives', action='store_true',
+  parser.add_option('-c', '--clean-old-firefox-archives', action='store_true',
                     help=('Clean old firefox archives; one will always be '
                           'kept as a fallback.'))
   options, _args = parser.parse_args()
   if not options.target_dir:
     parser.error('You must specify the target directory.')
 
   target_dir = options.target_dir
   if not os.path.isdir(target_dir):
     os.mkdir(target_dir)
 
   firefox_archive = _MaybeDownload(target_dir, options.force)
   if firefox_archive:
     return _ExtractArchive(firefox_archive, target_dir)
 
   if options.clean_old_archives:
     _CleanOldFirefoxArchives(target_dir)
 
 if __name__ == '__main__':
   sys.exit(main())