Ref count isolated uid usage in BatteryStats

Wakelock tracking in BatteryStats relies on the the isolated uid map
when tracking wakelocks from isolated uids. The map needs to keep the
isolated uid while it still has a  wakelock.

Bug: 194414351
Test: atest BatteryStatsNoteTest
Change-Id: I5e51f5f90191829d12fb080169520d9827b9906c
3 files changed