For now this relies on system libs and requires explicit opt-in
(skia_use_sfml=true).
[1] https://www.sfml-dev.org/
TBR=
Change-Id: Iff89efdb4494f79530d0d41dee80ff38d4e75671
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/310065
Reviewed-by: Florin Malita <fmalita@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>
