Fix _get_login for new upstream API

The changeset c9be44cd05e1 modifies the returned values of _get_login.

issue3975
review6411002
(grafted from 1a7d65a6b998d0c677396868aec350463845bd2f)

--HG--
branch : 3.2
extra : source : 1a7d65a6b998d0c677396868aec350463845bd2f