RFR: 8303681: JFR: RemoteRecordingStream::setMaxAge() should accept null

[Erik Gahlin]

Could I have a review of a PR that removes a Objects.requireNonNull from the setMaxAge method in the RemoteRecordingStream class. The check was accidentally added when the class was introduced in JDK 16. The specification states that null is accepted (similar to the Recording class). Max age is by default null, but can be set to another duration, for example Duration.ofHours(1), but not set back to null without this change. 

Testing: jdk/jdk/jfr

Thanks
Erik

-------------

Commit messages:
 - Initial

Changes: https://git.openjdk.org/jdk/pull/12886/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12886&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303681
  Stats: 4 lines in 2 files changed: 2 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/12886.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12886/head:pull/12886

PR: https://git.openjdk.org/jdk/pull/12886