Remove a small range of Tibetan characters from the allowed IDN set on Mac.

These characters do not display in the default macOS system font, despite the
font reporting that the glyphs are present.

BUG=714196
TBR=rsesek@chromium.org

(cherry picked from commit bccbe7c22a38f68da0c4d0bb9258060f2554e318)

Review-Url: https://codereview.chromium.org/2865213002
Cr-Original-Commit-Position: refs/heads/master@{#470407}
Change-Id: I96f412f602bf035d079caa0251ce3bc0de00181d
Reviewed-on: https://chromium-review.googlesource.com/535659
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/branch-heads/3071@{#788}
Cr-Branched-From: a106f0abbf69dad349d4aaf4bcc4f5d376dd2377-refs/heads/master@{#464641}
2 files changed