bzr-svn password prompt is not a unicode string

[Marcin Szałowicz]

If bzr-svn has to prompt for a password, it instead fails with this error:

bzr: ERROR: exceptions.ValueError: prompt '<svn://ip_svn:3690> xxxxxx-xxxx-xxxx-xxxx-xxxxxxxxx mySecretUserName password: ' not a unicode string

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 920, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 1131, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 673, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 695, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 136, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 166, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/builtins.py", line 1628, in run
    branch_location)
  File "/usr/lib/python2.7/dist-packages/bzrlib/controldir.py", line 778, in open_tree_or_branch
    controldir = klass.open(location)
  File "/usr/lib/python2.7/dist-packages/bzrlib/controldir.py", line 685, in open
    t = _mod_transport.get_transport(base, possible_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/transport/__init__.py", line 1679, in get_transport
    return get_transport_from_url(location_to_url(base), possible_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/transport/__init__.py", line 1654, in get_transport_from_url
    transport, last_err = _try_transport_factories(url, factory_list)
  File "/usr/lib/python2.7/dist-packages/bzrlib/transport/__init__.py", line 1686, in _try_transport_factories
    return factory.get_obj()(base), None
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/errors.py", line 141, in convert
    return unbound(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/transport.py", line 356, in __init__
    self.connections.add(self.connections.get(self.svn_url))
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/transport.py", line 329, in get
    return self.new(url)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/transport.py", line 297, in new
    return Connection(url, self.auth_baton, readonly=self.readonly)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/transport.py", line 241, in Connection
    config=config)
  File "/usr/lib/python2.7/dist-packages/subvertpy/ra.py", line 47, in RemoteAccess
    return url_handlers[type](url, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/auth.py", line 79, in get_svn_simple
    realm=realm, prompt="%s %s password" % (realm, username))
  File "/usr/lib/python2.7/dist-packages/bzrlib/config.py", line 2048, in get_password
    host=prompt_host, user=user)
  File "/usr/lib/python2.7/dist-packages/bzrlib/ui/text.py", line 249, in get_password
    self.prompt(prompt, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/ui/text.py", line 323, in prompt
    raise ValueError("prompt %r not a unicode string" % prompt)
ValueError: prompt '<svn://ip_svn:3690> xxxxxx-xxxx-xxxx-xxxx-xxxxxxxxx mySecretUserName password: ' not a unicode string