Deflake InattentiveSleep tests

Some inattentive sleep tests showed flakiness because of timing issues.
Adjusting sleeps helps increase chance scheduled messages have been
handled.
The change in PowerManagerService is for the case when
now == mLastUserActivityTime + attentiveTimeout.
updateAttentiveStateLocked considered this time as time to go to sleep,
but isAttentiveTimeoutExpired would report false for another millisecond
as it used > comparison instead of >= comparison.

Bug: 149340215
Test: atest --iterations 200 PowerManagerServiceTest#testInattentive*
Change-Id: Ibe5168664c1e01c6e480610686e19573c8df6c6f