RFR: Trim unused code from Shenandoah SA

[Roman Kennke]

> On 11/30/18 12:45 PM, Roman Kennke wrote:
>> There's quite a lot of code that can be trimmed out of Shenandoah SA
>> code, now that the broken heap walking is out.
>>
>> Testing: manual jstack test, hotspot_gc_shenandoah (ongoing)
>>
>> http://cr.openjdk.java.net/~rkennke/trim-shenandoah-sa/webrev.00/
> 
> Looks okay, *but* field renames should go in separately.
> 
> Look at it this way: we have to have the possibility to plainly revert all these changesets when
> heap iteration is back in order. Doing so with your current patch would revert the field renames too.

Right. Also, we can get rid of corresponding stuff in vmStructs too.
Hold on.

Roman