UI comment with code markdown:

You should still have

```assert_locked_or_safepoint(Threads_lock);```

for non-JavaThread access.

https://github.com/openjdk/jdk/pull/2535#discussion_r581521979

Text in email:

You should still have

(Threads_lock);```

for non-JavaThread access.

http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/2021-February/045779.html