hg: jdk9/jdk9/hotspot: 8185133: Reference pending list root might not get marked

[philip.race at oracle.com]

Changeset: 4a443796f6f5
Author:    mgerdin
Date:      2017-08-01 11:03 +0200
URL:       http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/4a443796f6f5

8185133: Reference pending list root might not get marked
Summary: Ensure that pending list head is marked by initial mark
Reviewed-by: eosterlund, kbarrett, tschatzl

! src/share/vm/gc/g1/g1CollectedHeap.cpp
! src/share/vm/memory/universe.cpp