* src/dispextern.h (FACE_FROM_ID_OR_NULL): Renamed from
FACE_OPT_FROM_ID; all callers changed.
* src/xdisp.c (extend_face_to_end_of_line): Call FACE_FROM_ID, not
FACE_FROM_ID_OR_NULL, as the resulting face is immediately
dereferenced.
(fill_gstring_glyph_string): Call FACE_FROM_ID, not
FACE_FROM_ID_OR_NULL, as the resulting face will be dereferenced
when the glyph string is drawn.
(BUILD_COMPOSITE_GLYPH_STRING): Call FACE_FROM_ID, not
FACE_FROM_ID_OR_NULL, as the resulting face will be dereferenced
in fill_composite_glyph_string.
(calc_line_height_property): Call FACE_FROM_ID_OR_NULL rather that
FACE_FROM_ID, since the function and its caller can cope with that
situation. Conflate 3 tests of missing face or font into just
one.
* src/xfaces.c (Fx_list_fonts, Fface_font, lookup_face): Call
FACE_FROM_ID_OR_NULL rather that FACE_FROM_ID, since these
functions can cope with that situation.
(lookup_derived_face): Don't call FACE_FROM_ID if the result will
not be used.
* src/w32console.c (w32_face_attributes): Remove redundant 'eassert'.