"webkit-patch upload" reports "mechanize._form_controls.ControlNotFoundError: no control matching name 'patch_id'"

I was using 252943@main.

Logging in as Hironori.Fujii@sony.com...
Fetching: https://bugs.webkit.org/show_bug.cgi?id=236061&ctype=xml&excludefield=attachmentdata
Obsoleting 1 old patch on bug 236061
Obsoleting attachment: 461289
Fetching: https://bugs.webkit.org/show_bug.cgi?id=236061&ctype=xml&excludefield=attachmentdata
Downloading whichcraft-0.6.1...
Installing whichcraft-0.6.1...
Installed whichcraft-0.6.1!
Adding patch "Patch for landing" to https://bugs.webkit.org/show_bug.cgi?id=236061
Submitting attachment 461290 [details] to EWS queues
Traceback (most recent call last):
  File "Tools/Scripts/webkit-patch", line 80, in <module>
    main()
  File "Tools/Scripts/webkit-patch", line 75, in main
    WebKitPatch(os.path.abspath(__file__)).main()
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/tool/multicommandtool.py", line 305, in main
    result = command.check_arguments_and_execute(options, args, self)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/tool/multicommandtool.py", line 123, in check_arguments_and_execute
    return self.execute(options, args, tool) or 0
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/tool/commands/abstractsequencedcommand.py", line 55, in execute
    self._sequence.run_and_handle_errors(tool, options, state)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/tool/commands/stepsequence.py", line 73, in run_and_handle_errors
    self._run(tool, options, state)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/tool/commands/stepsequence.py", line 67, in _run
    step(tool, options).run(state)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/tool/steps/submittoews.py", line 38, in run
    self._tool.ews_server.submit_to_ews(attachment_id)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/common/net/ewsserver.py", line 53, in submit_to_ews
    return NetworkTransaction().run(lambda: self._post_patch_to_ews(attachment_id))
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/common/net/networktransaction.py", line 58, in run
    return request()
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/common/net/ewsserver.py", line 53, in <lambda>
    return NetworkTransaction().run(lambda: self._post_patch_to_ews(attachment_id))
  File "/mnt/c/home/webkit/gb/Tools/Scripts/webkitpy/common/net/ewsserver.py", line 48, in _post_patch_to_ews
    self._browser['patch_id'] = unicode(attachment_id)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/libraries/autoinstalled/python-3-x86_64/mechanize/_mechanize.py", line 809, in __setitem__
    self.form[name] = val
  File "/mnt/c/home/webkit/gb/Tools/Scripts/libraries/autoinstalled/python-3-x86_64/mechanize/_form_controls.py", line 1963, in __setitem__
    control = self.find_control(name)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/libraries/autoinstalled/python-3-x86_64/mechanize/_form_controls.py", line 2355, in find_control
    return self._find_control(name, type, kind, id, label, predicate, nr)
  File "/mnt/c/home/webkit/gb/Tools/Scripts/libraries/autoinstalled/python-3-x86_64/mechanize/_form_controls.py", line 2448, in _find_control
    raise ControlNotFoundError("no control matching " + description)
mechanize._form_controls.ControlNotFoundError: no control matching name 'patch_id'