Fix Mac version for MacBookPro15,1 Change-Id: I2ddeb5c9bcf12efeccaf88cf24af109d97872507 Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1186616 Reviewed-by: Ben Wagner <bungeman@google.com> Commit-Queue: Ben Wagner <bungeman@google.com>