hg: shenandoah/jdk9/hotspot: Avoid touching metadata if class unloading is not requested.

[ashipile at redhat.com]

Changeset: 221b8cade588
Author:    shade
Date:      2017-01-24 10:58 +0100
URL:       http://hg.openjdk.java.net/shenandoah/jdk9/hotspot/rev/221b8cade588

 Avoid touching metadata if class unloading is not requested.

! src/share/vm/gc/shenandoah/shenandoahConcurrentMark.cpp
! src/share/vm/gc/shenandoah/shenandoahConcurrentMark.hpp
! src/share/vm/gc/shenandoah/shenandoahConcurrentMark.inline.hpp
! src/share/vm/gc/shenandoah/shenandoah_specialized_oop_closures.hpp