RFR: Disable evac assists for Traversal

[Aleksey Shipilev]

On 08/14/2018 01:15 PM, Aleksey Shipilev wrote:
> On 08/14/2018 01:10 PM, Roman Kennke wrote:
>> Have benchmarks shown this to be adversarial?
> 
> Yeah, evacuation stats show we evacuate much more in Java threads than usual, when assist is enabled
> for Traversal.

Oh wait. That is actually the performance bug in assist code. I retract this patch, Traversal can
actually benefit from evac assists.

-Aleksey