RFR: Several cleanups

[Roman Kennke]

Am 01.09.2018 um 10:08 schrieb Aleksey Shipilev:
> On 08/31/2018 11:30 PM, Roman Kennke wrote:
>> I went over the diff between shenandoah/jdk and jdk/jdk and found some
>> obvious leftovers:
>>
>> http://cr.openjdk.java.net/~rkennke/cleanups/webrev.00/
> 
> Looks good, except the bit in oop.cpp: are we actually safe doing HeapAccess (with barriers) for
> metadata? This came from the attempt to dodge barriers during oop_oop_iterate:
>   http://hg.openjdk.java.net/shenandoah/jdk/rev/fd9d711bcc6d
> 
> -Aleksey

I think yes, because it uses AS_NO_KEEPALIVE.