RFR (trivial) 8213211: [BACKOUT] Allow Klass::_subklass and _next_sibling to have unloaded classes

[coleen.phillimore at oracle.com]

Thanks Jesper and Jiangli.
Coleen

On 10/31/18 3:19 PM, Jiangli Zhou wrote:
> +1
>
> Thanks,
>
> Jiangli
>
>
> On 10/31/18 12:18 PM, jesper.wilhelmsson at oracle.com wrote:
>> Looks good!
>> /Jesper
>>
>>> On 31 Oct 2018, at 20:16, coleen.phillimore at oracle.com wrote:
>>>
>>> hg backout succeeded without any problems.   I made ErikO the 
>>> reviewer in the hg commit.
>>>
>>> open webrev at http://cr.openjdk.java.net/~coleenp/8213211.01/webrev
>>> bug link https://bugs.openjdk.java.net/browse/JDK-8213211
>>>
>>> There are several hangs.  One identified cause but others are iffy. 
>>> Would rather backout and go on vacation and fix it when I'm back and 
>>> mach5 is stable.
>>>
>>> Thanks,
>>> Coleen
>