OpenJDK 11: Merging in java.util.concurrent.atomic.AtomicReference

This is part of merging upstream changes from OpenJDK 11.28. It
updates the AtomicReference class.

Test: m
Test: atest libcore/ojluni
Test: atest AtomicReferenceTest
Bug: 188889082
Change-Id: Ic5ec50933b45da968445752af9d8eb963b60665c
3 files changed