hg: shenandoah/jdk9/hotspot: Fix shutdown/cancelled races.

[ashipile at redhat.com]

Changeset: 36b281f64016
Author:    shade
Date:      2016-12-08 16:36 +0100
URL:       http://hg.openjdk.java.net/shenandoah/jdk9/hotspot/rev/36b281f64016

Fix shutdown/cancelled races.

! src/share/vm/gc/shenandoah/shenandoahConcurrentThread.cpp
! src/share/vm/gc/shenandoah/shenandoahConcurrentThread.hpp
! src/share/vm/gc/shenandoah/shenandoahHeap.cpp
! src/share/vm/gc/shenandoah/shenandoahHeap.hpp