RFR: JDK-8176054 - [BACKOUT][REDO] G1 Needs pre barrier on dereference of weak JNI handles

[Kim Barrett]

> On Mar 2, 2017, at 11:51 AM, Jesper Wilhelmsson <jesper.wilhelmsson at oracle.com> wrote:
> 
> Hi,
> 
> Can I please have a couple of reviews for this backout of JDK-8175085?
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8176054
> 
> Webrev: http://cr.openjdk.java.net/~jwilhelm/8176054/webrev.00/
> 
> Thanks,
> /Jesper

Looks good.  (sigh)