Adjust Rectangle class to calculate rotated image dimensions according to libgd 2.2.2+

I came here from 🌱 [meta] Known intermittent, random, and environment-specific test failures Active and I'm struggling to see where this is up to. There is discussion on whether we should do this at all, then there is an MR, but then the MR was closed and a related issue was linked. The related issue is now closed (won't fix) so where does that leave this issue? Setting to PMNMI so we can get clarification on what's required.

mondrake → changed the visibility of the branch 2921123-adjust-rectangle-class to active.

mondrake → changed the visibility of the branch 2921123-adjust-rectangle-class to hidden.

Yeah this is messy now, probably better close this and start with a new issue aiming at fixing the test failure (if we want to, this is probably a rather edge case).

The original intent here was to refresh the Rectangle class with an algo that is more aligned with PHP 8. The calculations done currently are mirroring PHP 5 - this means that TransformDimensions consistently produce results that differ from the actual results of processing images via GD.

The main problem is that it’s difficult to target a ‘standard’ algo because PHP relies on the GD library to perform the actual processing, different versions return different results, and you cannot predict which version of GD is used by the PHP instance used for testing.

NR for #81

IIRC this change was done in PHP 7.1 so it's safe enough to use new approach, moreover there's not a lot of distros which shipping old GD library.
Moreover the most of PHP builds using bundled GD library

So let's close this for now, also based on feedback in https://drupal.slack.com/archives/C079NQPQUEN/p1742553484074889

Filed 📌 [consistent test failure] ImageDimensionsTest::testImageDimensions() Active as a replacement of this one.