The fix for JDK-8153224 Monitor deflation prolong safepoints has
been pushed to jdk-15+26. After JDK-8153224 has had sufficient
bake time (at least JDK16), the AsyncDeflateIdleMonitors option
and the safepoint based deflation mechanism can be removed.
JDK-8252126'GVars.stw_random = os::random()' lost by JDK-8246476
JDK-8254029ObjectMonitor cleanup/minor bug-fix changes extracted from JDK-8253064