Service: Keep services needing restart.

Services needing restart after crash include:
1) service with 'persistent == true'
2) service explicitly reuqired restart by returning START_STICKY
   or START_REDELIVER_INTENT from onStartCommand

Change-Id: Idc490a1ceb1e151a3eb7f34b7b4cf8058a06f34a
Signed-off-by: Liangcai Li <liangcail@nvidia.com>