[ActivityManager] Do not add service to reschedule after removing users.

Some service which has persistent attribute has restarted again and
again after removing users.
but it dies right after launching because it is not valid in owner mode.

This patch will check service's userId whether userId is alive or not.
And then if userId is not alive, then service will bring down.

Change-Id: Id99bf3c651b88e377f1fd6bec8aaad81318d7579