Apparently calibri.ttf does this:
https://github.com/fonttools/fonttools/pull/1094#discussion_r148933791

Fixes https://github.com/behdad/harfbuzz/issues/607

Fixes https://github.com/behdad/harfbuzz/pull/605

Part of fixing https://github.com/behdad/harfbuzz/pull/605

Found using `codespell -i 3 -w -I '../harf-whitelist.txt'`
whereas the whitelist contents were:
```
beng
iff
pres
ot
te
teh
```

Seems to work.  Yay!

Still to do: run kerning if GPOS doesn't have 'kern' feature.

Almost there.

Pushing this out early to catch bot errors since I'm using template tricks
we were not using in HarfBuzz before.

See https://github.com/behdad/harfbuzz/pull/590#issuecomment-341194673.

I simply removed the composite glyph and use the referenced simple
glyph directly.

This reverts commit 70137e2b.

Freetype and OT font functions give different positions for some glyphs
in this font (OT seems to be correct), but that is not what we are
interested in in this test.

See https://github.com/behdad/harfbuzz/pull/590#issuecomment-341045223.

https://github.com/behdad/harfbuzz/pull/590#issuecomment-340967271

These are CFF fonts and ot functions don’t support CFF glyph names yet.
The next commit will run all tests with ot functions.

https://github.com/behdad/harfbuzz/pull/592

Fixes https://github.com/behdad/harfbuzz/issues/589

See https://github.com/behdad/harfbuzz/pull/592