[autofit] Make autohint warping NORMAL option.

This moves warping option from LIGHT to NORMAL mode.  This makes LIGHT
truly void of hinting in x-direction, with left side bearing never
changed and right side bearing only altered by advance rounding.
Therefore, LIGHT is now ready to return fractional advance.  As a
NORMAL option, warping substitutes normal hinting.

* src/autofit/afcjk.c (af_cjk_hints_apply): Updated.
* src/autofit/aflatin.c (af_latin_hints_apply): Updated.
* src/autofit/aflatin2.c (af_latin2_hints_apply): Updated.

* src/autofit/afloader.c (af_loader_load_glyph): Handle warping
phantom points as normal.
5 files changed