In Khmer, a final subjoined consonant or independent vowel can occur
after matras. This final subjoined thing should NOT be reordered to
before the matra even though it's subjoined.
Fixes another 1k of the Khmer failures. Not much left really.
We are going to split matras without a Unicode decompositions in a way
that the second half takes the codepoint of the whole matra. So,
position them where the second half is supposed to end up.
And this, concludes the HarfBuzz Massala Hackfest.
I like to specially thank Jonathan Kew for doing all the decription and
letting me get commit points.
For dotted-circle independent clusters, Uniscribe does no Reph shaping
for the exact sequence Ra+Halant+25CC. Which also is the only possible
sequence with 25CC at the end.
This introduced a failure, which we tracked down to a test case like this:
U+092E,U+094B,U+094D,U+0930
The final character is a Ra that should be put in a syllable of it's
own. And we do. But it will interact with the Halant before it. So
now we finally are convinced that we have to limit features to syllable
boundaries. That's coming after lunch!