RFR (S): 8027559: Decrease code size and templatizing in G1ParCopyClosure::do_oop_work

[Thomas Schatzl]

Hi all,

  after the feedback from Stefan K. I split up the original change into
multiple changesets
(http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2014-February/009440.html).

I agree, as Stefan indicated, it makes reviewing easier.

Here is the first part.

Changes included:

- removed the unused _during_initial_mark, _mark_in_progress, _g1_rem
members from G1ParClosureSuper
- moved G1ParClosureSuper::_cm into G1ParCopyHelper as it is only used
there
- moved G1ParCopyClosure::mark_[forwarded_]object from G1ParCopyClosure
into G1ParCopyHelper to avoid the multiple instantiations of these
methods.
- some minor cleanup

CR:
https://bugs.openjdk.java.net/browse/JDK-8027559

Webrev:
http://cr.openjdk.java.net/~tschatzl/8027559/webrev.1/

Testing:
jprt

Thanks,
  Thomas