Revert "Revert "Revert^2 "Use the runtime's implementation for park/unpark"""

This reverts commit 782e160ebe8db9398ef39fcd84d2330eac825013.

Reason for revert: Fixing ThreadStress timeouts.

Change-Id: I94d8ea808afdd537800738fc242636e5b35485d9
3 files changed