[HarfBuzz] Javanese script in Harfbuzz

[R.S. Wihananto]

Hi, Behdad and every member!

I'm developing font for Javanese script based on Unicode on
http://sites.google.com/site/jawaunicode. Currently, my font only uses
SIL Graphite for smart shaping.
I see that recent versions of Firefox reorder U+A9BA JAVANESE VOWEL
SIGN TARUNG and U+A9BB JAVANESE VOWEL SIGN DIRGA MURE to the front of
base letter.

I tried to add OpenType table to my font using VOLT. I set the script
to 'Javanese <java>' and language to 'Default <dflt>'. I added
conjunct formation using 'blwf' and 'pstf' features. I tested the font
in Firefox but the conjunct was not formed. Nothing happened as if the
OpenType table ignored. Is there something wrong with my code or
Javanese script not implemented yet in Harfbuzz?

BTW, medial RA in Javanese (U+A9BF JAVANESE CONSONANT SIGN CAKRA) also
need reordering too.

Regards,
wihananto