Add ability to set topic during "git cl upload"

git_cl.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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.
 
 # Copyright (C) 2008 Evan Martin <martine@danga.com>
 
 """A git-command for integrating reviews on Rietveld and Gerrit."""
 
 from __future__ import print_function
@@ skipping 2614 matching lines @@
     if cc:
       refspec_opts.extend('cc=' + email.strip() for email in cc)
 
     reviewers = change_desc.get_reviewers()
     if reviewers:
       refspec_opts.extend('r=' + email.strip() for email in reviewers)
 
     if options.private:
       refspec_opts.append('draft')
 
+    if options.topic:
+      # Documentation on Gerrit topics is here:
+      # https://gerrit-review.googlesource.com/Documentation/user-upload.html#topic
+      refspec_opts.append('topic=%s' % options.topic)
+
     refspec_suffix = ''
     if refspec_opts:
       refspec_suffix = '%' + ','.join(refspec_opts)
       assert ' ' not in refspec_suffix, (
           'spaces not allowed in refspec: "%s"' % refspec_suffix)
     refspec = '%s:refs/for/%s%s' % (ref_to_push, branch, refspec_suffix)
 
     push_stdout = gclient_utils.CheckCallAndFilter(
         ['git', 'push', gerrit_remote, refspec],
         print_stdout=True,
@@ skipping 1280 matching lines @@
   parser.add_option('--target_branch',
                     '--target-branch',
                     metavar='TARGET',
                     help='Apply CL to remote ref TARGET.  ' +
                          'Default: remote branch head, or master')
   parser.add_option('--squash', action='store_true',
                     help='Squash multiple commits into one (Gerrit only)')
   parser.add_option('--no-squash', action='store_true',
                     help='Don\'t squash multiple commits into one ' +
                          '(Gerrit only)')
+  parser.add_option('--topic', default=None,
+                    help='Topic to specify when uploading (Gerrit only)')
   parser.add_option('--email', default=None,
                     help='email address to use to connect to Rietveld')
   parser.add_option('--tbr-owners', dest='tbr_owners', action='store_true',
                     help='add a set of OWNERS to TBR')
   parser.add_option('-d', '--cq-dry-run', dest='cq_dry_run',
                     action='store_true',
                     help='Send the patchset to do a CQ dry run right after '
                          'upload.')
   parser.add_option('--dependencies', action='store_true',
                     help='Uploads CLs of all the local branches that depend on '
@@ skipping 1344 matching lines @@
 if __name__ == '__main__':
   # These affect sys.stdout so do it outside of main() to simplify mocks in
   # unit testing.
   fix_encoding.fix_encoding()
   setup_color.init()
   try:
     sys.exit(main(sys.argv[1:]))
   except KeyboardInterrupt:
     sys.stderr.write('interrupted\n')
     sys.exit(1)