RFR: 8221558: Remove obsolete uses of OopStorage::ParState<'false, false> _par_state

[Stefan Karlsson]

Hi all,

Please review this patch to remove unused OopStorage::ParStates.

http://cr.openjdk.java.net/~stefank/8221558/webrev.01/
https://bugs.openjdk.java.net/browse/JDK-8221558

The StringTable was recently changed to be considered weak by all GCs, 
and the GCs were changed to use the WeakProcessor API to clean it. There 
are some left-overs from before that change.

Thanks,
StefanK