Revert^2 "Implement LockSupport.park with a futex"

Reason for revert: Fixed unused-argument compile error on mac

This resolves a contention issue where a thread unparking a higher
priority thread would see a bunch of repeated wakeups. It also resolves
an issue where LockSupport.parkUntil would not return on time if the
system clock changed while the thread was parked.

Bug: 28845097
Tested: ./test.py -b --host --verbose -j20
Change-Id: Iff71a0e23d0a9fbe072a092bec40a39192c195eb