[jdk18u] RFR: 8281638: jfr/event/allocation tests fail with release VMs after JDK-8281318 due to lack of -XX:+UnlockDiagnosticVMOptions [v3]

[Aleksey Shipilev]

> Follow-up for JDK-8281318 backport.
> 
> Additional testing: 
>  - [x] Linux x86_32 fastdebug, affected tests pass
>  - [x] Linux x86_32 release, affected tests pass

Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Merge branch 'master' into JDK-8281638-jfr-test-fixes
 - Backport d254cf28c5e72bd9b8de863b831015237640ca25
 - Backport 65831eb294b6f1f5f99988836c00005d41c27fd3

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

Changes:
  - all: https://git.openjdk.java.net/jdk18u/pull/43/files
  - new: https://git.openjdk.java.net/jdk18u/pull/43/files/4d9c60ca..9f27abbd

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk18u&pr=43&range=02
 - incr: https://webrevs.openjdk.java.net/?repo=jdk18u&pr=43&range=01-02

  Stats: 5301 lines in 149 files changed: 4244 ins; 637 del; 420 mod
  Patch: https://git.openjdk.java.net/jdk18u/pull/43.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk18u pull/43/head:pull/43

PR: https://git.openjdk.java.net/jdk18u/pull/43