PROXY: Mention that save_user()'s parameters are already qualified
Those comments are similar to what we have in the save_group() function.
Related:
https://fedorahosted.org/sssd/ticket/3134
Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>