Fix error message when using "gcl try nonexistentcl".

gcl.py

 #!/usr/bin/env python
 # Copyright (c) 2011 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.
 
 """\
 Wrapper script around Rietveld's upload.py that simplifies working with groups
 of files.
 """
 
@@ skipping 1291 matching lines @@
   # argument to trychange.py.
   # When the command is 'try' and --patchset is used, the patch to try
   # is on the Rietveld server.
   if not args:
     ErrorExit("You need to pass a change list name")
   if args[0].find(',') != -1:
     change_info = LoadChangelistInfoForMultiple(args[0], GetRepositoryRoot(),
                                                 True, True)
   else:
     change_info = ChangeInfo.Load(args[0], GetRepositoryRoot(),
-                                  False, True)
+                                  True, True)
   if change_info.GetFiles():
     args = args[1:]
   else:
     change_info = None
   return TryChange(change_info, args, swallow_exception=False)
 
 
 @attrs(usage='<old-name> <new-name>')
 def CMDrename(args):
   """Renames an existing change."""
@@ skipping 115 matching lines @@
       raise
     print >> sys.stderr, (
         'AppEngine is misbehaving and returned HTTP %d, again. Keep faith '
         'and retry or visit go/isgaeup.\n%s') % (e.code, str(e))
     return 1
 
 
 if __name__ == "__main__":
   fix_encoding.fix_encoding()
   sys.exit(main(sys.argv[1:]))