Fix git cl checkout when no branch has issues.

tests/git_cl_test.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.
 
 """Unit tests for git_cl.py."""
 
 import os
 import StringIO
 import stat
@@ skipping 1162 matching lines @@
     """Tests git cl checkout <issue>."""
     self.calls = self._checkout_calls()
     self.calls += [((['git', 'checkout', 'some-fix'], ), '')]
     self.assertEqual(0, git_cl.main(['checkout', '2222222222']))
 
   def test_checkout_not_found(self):
     """Tests git cl checkout <issue>."""
     self.calls = self._checkout_calls()
     self.assertEqual(1, git_cl.main(['checkout', '99999']))
 
+  def test_checkout_no_branch_issues(self):
+    """Tests git cl checkout <issue>."""
+    self.calls = [
+        ((['git', 'config', '--local', '--get-regexp',
+           'branch\\..*\\.rietveldissue'], ), '',
+         subprocess2.CalledProcessError(1, '', '', '', '')),
+        ((['git', 'config', '--local', '--get-regexp',
+           'branch\\..*\\.gerritissue'], ), '',
+         subprocess2.CalledProcessError(1, '', '', '', '')),
+
+    ]
+    self.assertEqual(1, git_cl.main(['checkout', '99999']))
+
 
 if __name__ == '__main__':
   git_cl.logging.basicConfig(
       level=git_cl.logging.DEBUG if '-v' in sys.argv else git_cl.logging.ERROR)
   unittest.main()