RFR: 8341261: Tests assume UnlockExperimentalVMOptions is disabled by default [v2]

[Todd V. Jonker]

> `-UnlockExperimentalVMOptions` isn't necessarily the default: a distro may enable it in order to default-enable other features like JVMCI/Graal.
> 
> I'm not entirely satisfied by adding a `@require` that only applies to a subset of the checks in a test class.  In `VMOptionWarning`, the experimental flag only applies to the first of the three scenarios it checks.  But I suspect this is a general problem with `@require`, and I'd be happy to hear suggestions on how to avoid disabling too much.

Todd V. Jonker has updated the pull request incrementally with two additional commits since the last revision:

 - Refactor VMOptionWarning for better scoping of @require
 - Use simpler vm.opt.final approach

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/21233/files
  - new: https://git.openjdk.org/jdk/pull/21233/files/e8e42d22..e63bd7f7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21233&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21233&range=00-01

  Stats: 73 lines in 4 files changed: 42 ins; 15 del; 16 mod
  Patch: https://git.openjdk.org/jdk/pull/21233.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21233/head:pull/21233

PR: https://git.openjdk.org/jdk/pull/21233