[HarfBuzz] Context matching

[Richard Wordingham]

On Mon, 14 Oct 2013 19:05:29 +0200
Behdad Esfahbod <behdad at behdad.org> wrote:

> Khaled, Richard, others, please test!!

At long last, I've repeated my context-related tests, using Version
0.9.22 plus commits up to 133eeba6a32769ec1a7520e7c8a0d2eb1ad986f8
time stamped Sun Oct 27 00:24:59 2013 +0200.

What worked in Version 0.9.18 still works.  Additionally, specifying
the character positions out of order for the subsidiary lookups also
works - in Version 0.9.18, it didn't.

Richard.