RFR: Traversal: Initialize extra liveness arrays when conc-threads > par-threads

[Aleksey Shipilev]

On 02/22/2018 12:19 PM, Roman Kennke wrote:
> http://cr.openjdk.java.net/~rkennke/init-extra-liveness/webrev.01/

I'd extend the existing block that has:
  ShenandoahGCPhase phase_prepare(ShenandoahPhaseTimings::traversal_gc_prepare);

...to cover this new path (and probably RP setup too) to monitor if that was a good idea.

Otherwise looks good.

Thanks,
-Aleksey