RFR: Adjust SA to reflect recent changes on JVM side

[Roman Kennke]

Good! Thanks!

Roman


> Recently upstreamed additional CollectedHeap APIs are slightly different
> from the ones when SA was implemented. Adjusting SA code to match recent
> changes on JVM side.
> 
> http://cr.openjdk.java.net/~zgu/shenandoah/sh-sa-refactor/webrev.00/index.html
> 
> 
> 
> Test:
> 
>   tier3_gc_shenandoah and hotspot_serviceability (fastdebug and release)
> 
> Thanks,
> 
> -Zhengyu