Set of utilities for Unicode comparison

Change-Id: If507499fd00e3a6a377aaecd9b343572c89295d1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/717300
Commit-Queue: Julia Lavrova <jlavrova@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
15 files changed