review(XS): 7119730: Tiered: SIGSEGV in AdvancedThresholdPolicy::is_method_profiled(methodOop)

[Igor Veresov]

Tiered can remove compile tasks that are stale from the queue and since this process involves locks it can safepoint. Because of that handles are required for heap references.
 
Webrev: http://cr.openjdk.java.net/~iveresov/7119730/webrev.00/

Thanks!igor