rev 11463 : Backport Traversal GC
*** 75,84 **** --- 75,85 ---- _shenandoah_stop_vm, _shenandoah_metadata_gc_clear_softrefs, _shenandoah_allocation_failure_evac, _shenandoah_concurrent_gc, + _shenandoah_traversal_gc, _shenandoah_upgrade_to_full_gc, _last_ditch_collection, _last_gc_cause };