RFR: 8325075: Enable -Werror for javadoc to fail on any warnings

[Johan Vos]

On Tue, 5 Mar 2024 16:47:45 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

> Now that the last of the javadoc warnings are fixed or suppressed, it is time to enable `-Werror` so that new javadoc warnings don't creep into our code base. The GHA run was successful.
> 
> You can see the `-Werror` doing its job in the following GHA workflow run on my [bad-8325075-javadoc-werror](https://github.com/kevinrushforth/jfx/tree/bad-8325075-javadoc-werror) branch, which has the patch from this PR applied on a base without Andy's fix for the last of the javadoc warnings:
> 
> https://github.com/kevinrushforth/jfx/actions/runs/8159524643/job/22304043414
> 
> That build fails with the expected error:
> 
> 
> 2024-03-05T16:23:29.6264357Z /home/runner/work/jfx/jfx/jfx/modules/javafx.web/src/main/java/javafx/scene/web/WebErrorEvent.java:125: warning: no comment
> 2024-03-05T16:23:29.6265947Z     private final String message;
> 2024-03-05T16:23:29.6266448Z                          ^
> 2024-03-05T16:23:29.6267675Z /home/runner/work/jfx/jfx/jfx/modules/javafx.web/src/main/java/javafx/scene/web/WebEvent.java:80: warning: no comment
> 2024-03-05T16:23:29.6269004Z     private final T data;
> 2024-03-05T16:23:29.6269667Z                     ^
> 2024-03-05T16:23:31.7938955Z error: warnings found and -Werror specified
> 2024-03-05T16:23:31.7939652Z Problems generating Javadoc.
> 2024-03-05T16:23:31.7940244Z 1 error
> 2024-03-05T16:23:31.7940590Z 91 warnings

This is major progress. Building works perfect, and with the patch applied to an older state of the repository it fails as expected.
This will enforce us to keep the JavaDoc clean (at least from a syntax point), good work.

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Marked as reviewed by jvos (Reviewer).

PR Review: https://git.openjdk.org/jfx/pull/1390#pullrequestreview-1917757644