Simplifies maintenance for Value Objects: Unsafe reference comparison is no longer the same as `==`, let's use VarHandle which is always up-to-date.
--------- - [x] I confirm that I make this contribution in accordance with the [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). ------------- Commit messages: - Add micro case - Merge branch 'master' of https://github.com/openjdk/jdk into fix/atomic-reference-field-updater-use-var-handle - Convert AtomicReferenceFieldUpdater to use VarHandle Changes: https://git.openjdk.org/jdk/pull/31924/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=31924&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8388887 Stats: 44 lines in 4 files changed: 31 ins; 0 del; 13 mod Patch: https://git.openjdk.org/jdk/pull/31924.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/31924/head:pull/31924 PR: https://git.openjdk.org/jdk/pull/31924
