hg: shenandoah/jdk10: [backport] Fix assert in ShenandoahTraversalGC

[roman at kennke.org]

Changeset: c9caa1375ae0
Author:    rkennke
Date:      2018-06-26 19:24 +0200
URL:       http://hg.openjdk.java.net/shenandoah/jdk10/rev/c9caa1375ae0

[backport] Fix assert in ShenandoahTraversalGC

! src/hotspot/share/gc/shenandoah/shenandoahTraversalGC.cpp