Catching IllegalStateException while device is going to shutdown

NetworkStatsService calling unregisterTetheringEventCallback
occasionally meet IllegalStateException throw from TetheringManager,
simply catch the exception and continue following shutdown procedure
as losing network stack has no impact at this point of time.

Bug: 273459595
Change-Id: Ib87901775668caf10108ece0f78da738a6fe2692
1 file changed