[8] RFR: Fix naked heap loads in HeapDumper

[Roman Kennke]

Yes, please.

Thanks,
Roman


> Trivial thing for sh/jdk8, follows what JDK-8199328 is doing:
> 
> diff -r a56f86355f8d src/share/vm/services/heapDumper.cpp
> --- a/src/share/vm/services/heapDumper.cpp      Thu Oct 31 12:50:02 2019 +0100
> +++ b/src/share/vm/services/heapDumper.cpp      Mon Nov 04 11:35:57 2019 +0100
> @@ -720,10 +720,16 @@
>          o = oopDesc::load_decode_heap_oop((narrowOop*)addr);
>        } else {
>          o = oopDesc::load_decode_heap_oop((oop*)addr);
>        }
> 
> +#if INCLUDE_ALL_GCS
> +      if (UseShenandoahGC) {
> +        o = ShenandoahBarrierSet::barrier_set()->load_reference_barrier(o);
> +      }
> +#endif
> +
>        // reflection and sun.misc.Unsafe classes may have a reference to a
>        // Klass* so filter it out.
>        assert(o->is_oop_or_null(), "should always be an oop");
>        writer->write_objectID(o);
>        break;
> 
> Testing: hotspot_gc_shenandoah {fastdebug, release}
>