Various clang 8.0 static analyzer fixes.

Reported by Sender Ghost <lightside@gmx.com>.

* src/autofit/afcjk.c (af_cjk_hints_compute_edges): Catch a corner
case where `edge->first' could be NULL.

* src/pfr/pfrobjs.c (pfr_slot_load): Remove unnecessary test of
`size'.

* src/raster/ftraster.c (Draw_Sweep): Catch a corner case where
`draw_right' might be NULL.

* src/sfnt/ttmtx.c (tt_face_get_metrics): Fix limit test for
`aadvance'.
Ensure `abearing' always hold a meaningful result.

* src/truetype/ttgload.c (load_truetype_glyph): Ensure `subglyph' is
not NULL before accessing it.
* src/truetype/ttgxvar.c (TT_Set_Named_Instance): Remove unnecessary
test of `namedstyle'.

* src/type42/t42parse.c (t42_parser_done): Ensure
`parser->root.funcs.done' is not NULL before accessing it.
9 files changed