[lworld] RFR: 8328543: [lworld] Library and test updates to use --enable-preview instead of ValhallaFeatures [v7]

[Mandy Chung]

On Thu, 28 Mar 2024 20:14:00 GMT, Roger Riggs <rriggs at openjdk.org> wrote:

>> Update AccessFlag and tests to JEP 401 and use of --enable-preview instead of ValhallaFeatures.
>> Minor formatting change to java.lang.Character to allow it to be a value class with --enable-preview.
>> (The class file format version numbers will need to be updated when re-synching with the mainline).
>
> Roger Riggs has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Preview and non-preview tests cannot be supported by a single test due to compilation of value classes.
>   Moved preview support for access flags to a new test (ClassAccessFlagPreviewTest) to be run only with --enable-preview.
>   Reverted all changes to ClassAccessFlagTest and will only run when not --enable-preview.

Marked as reviewed by mchung (Committer).

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

PR Review: https://git.openjdk.org/valhalla/pull/1060#pullrequestreview-1971790349