This speeds up FreeType's handling of malformed fonts.
* src/truetype/ttinterp.c (TT_RunIns): Set up limits for the number
of twilight points, the total number of negative jumps, and the
total number of loops in LOOPCALL opcodes. The values are based on
the number of points and entries in the CVT table.
(Ins_JMPR): Test negative jump counter.
(Ins_LOOPCALL): Test loopcall counter.
* src/truetype/ttinterp.h (TT_ExecContext): Updated.
* docs/CHANGES: Updated.