hg: jdk/jdk: 8221724: Enable archiving of Strings with hash 0

[claes.redestad at oracle.com]

Changeset: 40a7e2fc9beb
Author:    redestad
Date:      2019-04-02 11:37 +0200
URL:       http://hg.openjdk.java.net/jdk/jdk/rev/40a7e2fc9beb

8221724: Enable archiving of Strings with hash 0
Reviewed-by: jiangli, iklam

! src/hotspot/share/classfile/stringTable.cpp
! src/hotspot/share/oops/constantPool.cpp
! test/hotspot/jtreg/runtime/appcds/sharedStrings/HelloStringPlus.java
! test/hotspot/jtreg/runtime/appcds/sharedStrings/LockStringTest.java