RFR: 8319072: JFR: Turn off events for JFR.view

[Erik Gahlin]

Could I have a review of a change that disables events for the Attach thread when executing the diagnostic command JFR.view. The rationale is to avoid exception events etc. that create noise in the output making troubleshooting the application harder. I also removed an incorrect comment.

I'm not a fan of overrides that return boolean values, but it was hard to come up with something better without a large refactoring, or adding boilerplate code to the other diagnostic commands.

Testing: idk/jdk/jfr




Thanks
Erik

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Commit messages:
 - Initial

Changes: https://git.openjdk.org/jdk/pull/16936/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16936&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319072
  Stats: 24 lines in 3 files changed: 23 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/16936.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16936/head:pull/16936

PR: https://git.openjdk.org/jdk/pull/16936