Roll HarfBuzz

https://chromium.googlesource.com/external/github.com/harfbuzz/harfbuzz.git/+log/8be74d8553453..1e06282105a2

This changes the upstream to github (where actual work is now done) and
picks up AAT work so we can drop the (buggy) CoreText backend on Mac.

Change-Id: Ib3fbbb8e07910d570e70489b4e78a9cb6fac3630
Reviewed-on: https://skia-review.googlesource.com/c/189876
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Hal Canary <halcanary@google.com>
9 files changed