RFR [9] 2018-03-26: Bulk backports to sh/jdk9

[Roman Kennke]

Am 26.03.2018 um 15:31 schrieb Aleksey Shipilev:
> This backports last week's work to sh/jdk9:
> 
> [backport] Remove narrowOop variants of oopDesc::equals and related methods
> [backport] Keep track of per-cycle mutator/collector allocs. Fix mutator/collector alloc region
> overlap in traversal.
> [backport] Rename and cleanup _regions and _free_set uses
> [backport] Full GC should not trash empty regions
> 
> Testing: hotspot_gc_shenandoah {fastdebug|release}
> 
> Thanks,
> -Aleksey
> 

There's no webrev linked here.

Roman