RFR: 8146989: Introduce per-worker preserved mark stacks in ParNew

[Thomas Schatzl]

Hi all,

  sorry for the delay, I have been somewhat unavailable for the last 1
1/2 weeks...

On Wed, 2016-02-17 at 13:31 -0500, Tony Printezis wrote:
> Thanks Thomas! Did it go through JPRT OK?

  yes, also running some basic VM tests.

Pushing right now, should be in the repo in ~2 hours. Fixed the
copyright dates before that.

Thanks,
  Thomas