Avoid unnecessary volatile write on new AtomicBoolean(false)

[Christoph Dreis]

Hi,

forgive me if this is not the right approach after the move to GitHub, but apparently there was no mail sent to the mailing list with this one.
I’ve opened https://github.com/openjdk/jdk/pull/510  to improve the performance of calls to new AtomicBoolean(false).

The mentioned PR would need sponsoring from someone, which I would highly appreciate.
If there's any change to the sponsoring process, please let me know as well.

Cheers,
Christoph