AlarmMangerService: Fix the delay of ACTION_TIME_CHANGED for time-services

After boot completed, if low memory condition happens or some ordered
broadcasts have time out, it will cause delay for some receivers to
receive ordered broadcasts. Adding FLAG_RECEIVER_FOREGROUND into
time changed action will make TimeServiceBroadcastReceiver receive
ACTION_TIME_CHANGED in time.

CRs-Fixed: 630982
Change-Id: Id789d0b3c969af6b92f62612602ba119613382ab