git: openjdk/jdk: 8250563: Add KVHashtable::add_if_absent

[Ioi Lam]

Changeset: 001e51d9
Author:    Ioi Lam <iklam at openjdk.org>
Date:      2020-09-08 18:27:59 +0000
URL:       https://git.openjdk.java.net/jdk/commit/001e51d9

8250563: Add KVHashtable::add_if_absent

Reviewed-by: ccheung, coleenp

! src/hotspot/share/memory/archiveBuilder.cpp
! src/hotspot/share/memory/metaspaceClosure.cpp
! src/hotspot/share/utilities/hashtable.hpp
! src/hotspot/share/utilities/resourceHash.hpp