Roll FreeType from 26adb9ff to b91f75bd (3 commits)

https://chromium.googlesource.com/chromium/src/third_party/freetype2.git/+log/26adb9ff98f9ea002c8d22a43d0d3c0c9534d40b..b91f75bd02db43b06d634591eb286d3eb0ce3b65

Change-Id: I48c34ee1281b152e70837cd70dbed3dd7a70fc27
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1137996
Auto-Submit: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>
Reviewed-by: Florin Malita <fmalita@google.com>