It can be the same with a parent one and the helper will inherit all
parent resources.

Now we can dereference item->ids for all task. It's used in
restore_task_mnt_ns, for example.

Reported-by: Mr Jenkins
Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>