Using options.email for svn credential is not a good idea.

trychange.py

 #!/usr/bin/python
 # 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.
 """Client-side script to send a try job to the try server. It communicates to
 the try server by either writting to a svn repository or by directly connecting
 to the server by HTTP.
 """
 
 import datetime
@@ skipping 316 matching lines @@
   if options.dry_run:
     return
 
   # Do an empty checkout.
   temp_dir = tempfile.mkdtemp()
   temp_file = tempfile.NamedTemporaryFile()
   try:
     try:
       command = ['svn', 'checkout', '--depth', 'empty', '-q',
                  options.svn_repo, temp_dir]
-      if options.email:
-        command.extend(['--username', options.email])
       gclient_utils.CheckCall(command)
 
       # TODO(maruel): Use a subdirectory per user?
       current_time = str(datetime.datetime.now()).replace(':', '.')
       file_name = (EscapeDot(options.user) + '.' + EscapeDot(options.name) +
                    '.%s.diff' % current_time)
       full_path = os.path.join(temp_dir, file_name)
       full_url = options.svn_repo + '/' + file_name
       file_found = False
       try:
@@ skipping 337 matching lines @@
   except (InvalidScript, NoTryServerAccess), e:
     if swallow_exception:
       return 1
     print e
     return 1
   return 0
 
 
 if __name__ == "__main__":
   sys.exit(TryChange(None, [], False))