Pass-through of variable COLRv1 RuntimeEnabled Blink feature flag

Enable passing in a feature-test function that returns a Boolean
with the intention of being able to use it in FreeType library
initialisation.

See also:
https://gitlab.freedesktop.org/freetype/freetype/-/merge_requests/168

Bug: skia:13448
Change-Id: I6c985201552b54f2fa99e911265b7303ff8b2897
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/551637
Commit-Queue: Dominik Röttsches <drott@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Florin Malita <fmalita@google.com>
2 files changed