RFR (S) 8224151: Test vmTestbase/nsk/sysdict/vm/stress/chain/chain007/chain007.java might hang with release binaries

[Lois Foltan]

Looks good.
Lois

On 6/5/2019 9:53 PM, coleen.phillimore at oracle.com wrote:
> Summary: Fix deadlock on ClassLoaderDataGraph_lock and g1 
> clear_claimed_marks.
>
> Thank you to Stefan for finding the deadlock and Thomas for 
> suggestions on the fix, plus text for comments.
>
> Tested with this test 100s of times, tier1-3 and tier6 almost complete.
>
> open webrev at http://cr.openjdk.java.net/~coleenp/2019/8224151.01/webrev
> bug link https://bugs.openjdk.java.net/browse/JDK-8224151
>
> Thanks,
> Coleen