hg: shenandoah/jdk11: Revert unnecessary additions to ciInstanceKlass and fieldDescriptor

[shade at redhat.com]

Changeset: 32f771dcb590
Author:    shade
Date:      2019-08-20 21:44 +0200
URL:       https://hg.openjdk.java.net/shenandoah/jdk11/rev/32f771dcb590

Revert unnecessary additions to ciInstanceKlass and fieldDescriptor

! src/hotspot/share/ci/ciInstanceKlass.cpp
! src/hotspot/share/ci/ciInstanceKlass.hpp
! src/hotspot/share/runtime/fieldDescriptor.hpp