RFR: 8370498: Improve how Node detects whether a layout property change requires a new layout pass [v4]

[John Hendrikx]

On Thu, 30 Oct 2025 15:01:55 GMT, Marius Hanl <mhanl at openjdk.org> wrote:

> This is good information I even did not know in full detail (although it looks like I made this correct for my own components, because I did what JavaFX is doing).
> Having warnings or information for that would be nice. Since we now can detect correctly when we layout children, we may can detect is something triggered another CSS pass although it should better not do that now, and what to do instead. This way, even is something now breaks, we could get information why this unusual combination does not work as expected.

Yeah, I discovered this one in a dark-mode application, where I was adding new cells (on demand) during layout, and I noticed a brief white flash.  Solved it with `Scene::addPreLayoutListener`.  No idea what the virtual flows do :)

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PR Comment: https://git.openjdk.org/jfx/pull/1945#issuecomment-3469370242