RFR(XS): JDK-8199780: SetMemory0 and CopyMemory0 in unsafe.cpp need to resolve their operands

[Roman Kennke]

 SetMemory0 and CopyMemory0 in unsafe.cpp read and write from/to
objects, and thus need to resolve their operands via Access::resolve()
before accessing them.

Bug:
https://bugs.openjdk.java.net/browse/JDK-8199780
Webrev:
http://cr.openjdk.java.net/~rkennke/JDK-8199780/webrev.00/

I'll say again that I'd prefer resolve_for_read() and
resolve_for_write(), but for now the strong resolve() will suffice. ;-)

Can I please get a review?

Roman