[8u] RFA for JDK-8153176: Long pause in ParOldGC, because ParallelTaskTerminator peeks wrong TaskQueueSet

[Shafi Ahmad]

Hi,

Please approve this clean backport of ' JDK-8153176: Long pause in ParOldGC, because ParallelTaskTerminator peeks wrong TaskQueueSet' to 8u-dev.
Please note the backport is clean after changing the path from " src/share/vm/gc/parallel/" to " src/share/vm/gc_implementation/parallelScavenge/" in the original changeset. 

Jdk9 Bug: https://bugs.openjdk.java.net/browse/JDK-8153176
Review link: http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-March/017456.html
	         http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2016-April/017484.html
Jdk9 changeset: http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/d19a9badb2df

Testing: jprt 

Regards,
Shafi