RFR: 8355522: Remove the `java.locale.useOldISOCodes` system property [v4]

[Justin Lu]

On Wed, 23 Jul 2025 17:39:12 GMT, Naoto Sato <naoto at openjdk.org> wrote:

>> This PR removes the system property deprecated in JDK 25. If the property is specified at runtime, a warning will be emitted at startup to inform the user that the value is ignored. A corresponding CSR has been drafted as well
>
> Naoto Sato has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Further wording refinement

Now that PR is open again, did another take and looks good as before. Minor test comments.

test/jdk/java/util/Locale/LocaleTest.java line 712:

> 710:         Locale indonesianNew = Locale.of("id");
> 711: 
> 712:         if (!hebrewOld.getLanguage().equals("he")) {

Since we are using JUnit, these assertions would be cleaner as `assertEquals`.

test/jdk/java/util/Locale/LocaleTest.java line 714:

> 712:         if (!hebrewOld.getLanguage().equals("he")) {
> 713:             fail("Got back wrong language code for old Hebrew: expected \"he\", got \""
> 714:                     + hebrewNew.getLanguage() + "\"");

Here and below, I think these errors should be including the old language in the fail message, not the new language. i.e. `hebrewOld.getLanguage` instead of `hebrewNew.getLanguage`.

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

PR Review: https://git.openjdk.org/jdk/pull/26419#pullrequestreview-3553326987
PR Review Comment: https://git.openjdk.org/jdk/pull/26419#discussion_r2599560414
PR Review Comment: https://git.openjdk.org/jdk/pull/26419#discussion_r2599581669