RFR: 8361424: Eliminate Log methods mandatoryWarning() and mandatoryNote()

[Maurizio Cimadamore]

On Fri, 4 Jul 2025 18:24:50 GMT, Archie Cobbs <acobbs at openjdk.org> wrote:

> The fix for [JDK-8359493](https://bugs.openjdk.org/browse/JDK-8359493) added the ability to associate `DiagnosticFlag`'s to specific warnings at the point of definition in `compiler.properties`. In cases where the flag is an inherent property of the warning itself, `compiler.properties` is a more appropriate place to declare it, instead of having to add it at all the points in the codebase where that particular warning is used.
> 
> In particular, the Log API methods `mandatoryWarning()` and `mandatoryNote()` can be removed, as they serve only to add the `MANDATORY` flag to warnings and notes for which "mandatoryness" is inherent. Doing so should help decomplexify the code a bit.

Marked as reviewed by mcimadamore (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/26138#pullrequestreview-3031120708