RFR: Move Shenandoah stubs generation into ShenandoahBarrierSetAssembler

[Aleksey Shipilev]

On 06/14/2018 05:21 PM, Roman Kennke wrote:
> Incremental:
> http://cr.openjdk.java.net/~rkennke/shstubgen/webrev.04.diff/
> Full:
> http://cr.openjdk.java.net/~rkennke/shstubgen/webrev.04/

Yup, looks good!

Thanks,
-Aleksey