This should fix the various issues with colours in Ogg Theora and WEBM playback.
(A reference project is attached to PR #26051, which this commit should be part of.)
This version of the commit, rather than moving x->RGBA handling into libsimplewebm, uses a colourspace field added to libsimplewebm by a PR there.
Thus, the commit that precedes this should be the synchronization & cleanup commit for that.
Also, this version is now clang-format friendly. I hope.
This allows more consistency in the manner we include core headers,
where previously there would be a mix of absolute, relative and
include path-dependent includes.
20kdc
Rémi Verschelde