WebEngine Opentype SVG colour font support (patches attached)

Upstream issue:

https://bugs.chromium.org/p/chromium/issues/detail?id=306078

although it was marked as "WONT FIX" in 2021, Google engineers actually did most of the work in 2022, but left it disabled. Attached are two patches which switches opentype SVG support on. Tested against patched 6.7.0 Beta 1.

The patches and the CI to build the fedora RPMS are on https://github.com/HinTak/Qt6WE-OT-SVG/ and tested with PyQt6 in https://github.com/HinTak/minimal-web-browsers/

. In a nutshell, try visiting either  https://yoksel.github.io/color-fonts-demo/ or  https://pixelambacht.nl/chromacheck/ before and after applying the patches.

They are discussed in https://github.com/HinTak/chromium-mod-CI  .