hg: shenandoah/jdk10: ShenandoahVerifyOptoBarriers should not fail with disabled barriers

[ashipile at redhat.com]

Changeset: 9cafa38b1ef1
Author:    shade
Date:      2017-12-04 18:41 +0100
URL:       http://hg.openjdk.java.net/shenandoah/jdk10/rev/9cafa38b1ef1

ShenandoahVerifyOptoBarriers should not fail with disabled barriers

! src/hotspot/share/opto/compile.cpp
! src/hotspot/share/opto/shenandoahSupport.cpp
! src/hotspot/share/opto/shenandoahSupport.hpp
! src/hotspot/share/runtime/arguments.cpp
! test/hotspot/jtreg/gc/shenandoah/TestSelectiveBarrierFlags.java