hg: shenandoah/jdk: Move BiasedLocking and general mark preservation to prolog/epilog

[shade at redhat.com]

Changeset: 50d6ac06b5a9
Author:    shade
Date:      2019-05-14 20:16 +0200
URL:       http://hg.openjdk.java.net/shenandoah/jdk/rev/50d6ac06b5a9

Move BiasedLocking and general mark preservation to prolog/epilog

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