RFR: Improve inlining of the root scanning closure in partial GC

[Roman Kennke]

As $SUBJECT says. It generates inlined oop iterators for the
PartialEvacuateUpdateHeapClosure, and thus speeds up root region scanning.

http://cr.openjdk.java.net/~rkennke/inline-partial-closures/webrev.00/
<http://cr.openjdk.java.net/%7Erkennke/inline-partial-closures/webrev.00/>

Roman