Update subseting expected files to match latest version of fontTools.
- subset class def 1 against the coverage table. - Don't re-use class 0 in class def 2. - Ignore class 0 glyphs for the purposes of determing format 1 vs format 2 encoding for ClassDef. Add an additional test case which demonstrates these issues.
do subset based on variation indices collected in step 1
Garret Rieger
Qunxin Liu