Fixes https://github.com/behdad/harfbuzz/issues/243
With javatext.ttf, the reodering medial Ra gets its advance width
zero'ed in Uniscribe implementation, and the font adds the advance
back. Our Indic shaper does not do that, but USE does. So, route
Javanese through USE. That's what Microsoft does anyway. Test:
U+A9A5,U+A9BA
This also seems to fix the following sequence, and variations thereof:
U+A99F,U+A9C0,U+A9A2,U+A9BF
In Khmer coeng model, a V,Ra can go *after* matras. If it goes after a
split matra, it should be reordered to *before* the left part of such matra.
Khmer failures down from 136 to 39 (0.0130381%).
Mark stuff after a pre-base reordering Ro 'cfar'. Used in Khmer.
This allows distinguishing the following cases with MS Khmer fonts:
U+1784,U+17D2,U+179A,U+17D2,U+1782
U+1784,U+17D2,U+1782,U+17D2,U+179A
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.
Amend the syllable structure to allow a final subscripted consonant
(Coeng+C) and a final subscripted independent vowel (Coeng+V).
Fixes another 2k of Khmer failures.