remove legacy hinting-enum guards

Bug: skia:
Change-Id: I762fd834859fc6334b4eb36c1fad05538e873dd9
Reviewed-on: https://skia-review.googlesource.com/c/173229
Reviewed-by: Florin Malita <fmalita@chromium.org>
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Reed <reed@google.com>
5 files changed