Since the Blink side CTFontRefs are no longer created from CGFontRefs
after [1], we do not need to pass CGFontRefs to Skia any longer for
keeping them alive. Clean up related plumbing which previously passed
through the CGFontRef to the SkTypefaceMac constructor.
[1] https://chromium-review.googlesource.com/c/chromium/src/+/1964073
Bug: chromium:1033478
Change-Id: Ic85cae6289fa9b4886201c92defb54fcc5622720
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/266816
Reviewed-by: Dominik Röttsches <drott@chromium.org>
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
c9b06ca708