Instead of passing --author, lets just set the name/email for the repo temporarily.

checkout.py

 # coding=utf8
 # 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.
 """Manages a project checkout.
 
 Includes support for svn, git-svn and git.
 """
 
 import ConfigParser
@@ skipping 695 matching lines @@
         raise PatchApplicationFailed(
             p,
             'While running %s;\n%s%s' % (
               ' '.join(e.cmd),
               align_stdout(stdout),
               align_stdout([getattr(e, 'stdout', '')])))
     # Once all the patches are processed and added to the index, commit the
     # index.
     cmd = ['commit', '-m', 'Committed patch']
     if name and email:
-      author = '%s <%s>' % (name, email)
-      cmd.extend(['--author', author])
+      cmd = ['-c', 'user.email=%s' % email, '-c', 'user.name=%s' % name] + cmd
     if verbose:
       cmd.append('--verbose')
     self._check_call_git(cmd)
     if self.base_ref:
       base_ref = self.base_ref
     else:
       base_ref = '%s/%s' % (self.remote,
                             self.remote_branch or self.master_branch)
     found_files = self._check_output_git(
         ['diff', base_ref,
@@ skipping 110 matching lines @@
   def revisions(self, rev1, rev2):
     return self.checkout.revisions(rev1, rev2)
 
   @property
   def project_name(self):
     return self.checkout.project_name
 
   @property
   def project_path(self):
     return self.checkout.project_path