git: openjdk/jdk17: 8262841: Clarify the behavior of PhantomReference::refersTo

[Mandy Chung]

Changeset: 9ac63a6e
Author:    Mandy Chung <mchung at openjdk.org>
Date:      2021-06-30 22:43:23 +0000
URL:       https://git.openjdk.java.net/jdk17/commit/9ac63a6e08c18ed99b97fe0abcc0ac51b96a563e

8262841: Clarify the behavior of PhantomReference::refersTo

Reviewed-by: kbarrett, rriggs

! src/java.base/share/classes/java/lang/ref/PhantomReference.java