RFR: JDK-8297215: Update libs tests to use @enablePreview [v4]

[Erik Gahlin]

On Thu, 1 Dec 2022 18:00:11 GMT, Joe Darcy <darcy at openjdk.org> wrote:

>> Similar to an update recently done for langtools tests, update the libraries regression tests to take advantage of the @enablePreview jtreg feature.
>
> Joe Darcy has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Respond to review feedback.

test/jdk/jdk/jfr/threading/TestDeepVirtualStackTrace.java line 46:

> 44:  * @modules jdk.jfr/jdk.jfr.internal
> 45:  * @enablePreview
> 46:  * @compile TestDeepVirtualStackTrace.java

Is compilation needed here?

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PR: https://git.openjdk.org/jdk/pull/11222