RFR: 8370905: Update vm.defmeth tests to use virtual threads [v2]

[Leonid Mesnik]

On Mon, 1 Dec 2025 19:22:11 GMT, Leonid Mesnik <lmesnik at openjdk.org> wrote:

>> The vm.defmeth stress tests should use
>> `TestThreadFactory.newThread()`
>> to start virtual threads if test thread factory is used.
>
> Leonid Mesnik 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:
> 
>  - removed setName
>  - Merge branch 'master' of https://github.com/openjdk/jdk into 8370905
>  - 8370905: Update vm.defmeth tests to use virtual threads

Removed setName()

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

PR Review: https://git.openjdk.org/jdk/pull/28048#pullrequestreview-3526136121