RFR (S): 8191567: Refactor ciInstanceKlass G1 keep alive barrier to use Access API.

[Thomas Schatzl]

Hi,

On Fri, 2017-11-24 at 17:22 +0100, Erik Österlund wrote:
> Hi,
> 
> When creating a ciInstanceKlass handle, G1 might need a SATB barrier
> to keep "peeked" weak klass pointers alive during marking.
> This should now be done with the Access API instead of manual calls
> to the G1 SATB barrier.
> 
> Bug:
> https://bugs.openjdk.java.net/browse/JDK-8191567
> 
> Webrev:
> http://cr.openjdk.java.net/~eosterlund/8191567/webrev.00/

  looks good.

Thanks for providing such nice usage examples for the new Access klass
separately from the huge Access change :)

Thanks,
  Thomas