(Mlatin): Don't declare it here.

(Mlatin): Don't declare it here.
(visual_order): Fix reordering of combining characters.
(compose_glyph_string): Fix detection of script.
(layout_glyphs): Don't fix reordering of combining characters
here.
(layout_glyph_string): Pay attention to
control->disable_overlapping_adjustment.
(truncate_gstring): Include at least on character in a line.
(get_gstring): Always scan one full line.
(mdraw__init): Don't initialize Mlatin here.
(mdraw_text_per_char_extents): Fix iteration.  If a glyph doesn't
have a font, use ascent/descent of an ASCII font.  Allow
ink_array_return and logical_array_return to be NULL.
(mdraw_coordinates_position): Fix iteration.