bug#11850: bug#11813: bug#11850: crash (null font) running emacs built from git

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> (gdb) p s->f->output_data.x->font
> (gdb) p *(s->f->output_data.x->font)

(gdb) frame 3
#3  0x000000000048eb18 in fill_glyphless_glyph_string
(s=0x7fffffffba40, face_id=13, start=8, end=68, overlaps=0) at
xdisp.c:22578
22578     eassert (s->font);
(gdb) p s->f->output_data.x->font
$1 = (struct font *) 0x146efd8
(gdb) p *(s->f->output_data.x->font)
$2 = {header = {size = 4611686018429485074, next = {nbytes = 264,
buffer = 0x108, vector = 0x108}}, props = {15296386, 15541218,
15541266, 15541170, 15362930, 102728, 102532, 102656, 68,
    400, 0, 400, 18785894, 15120722, 15558113, 15558113, 15120722,
15296386}, max_width = 40, pixel_size = 17, height = 18, space_width =
10, average_width = 10, min_width = 10,
  ascent = 14, descent = 4, underline_thickness = 1,
underline_position = 2, vertical_centering = 0, encoding_type = 0
'\000', baseline_offset = 0, relative_compose = 0,
  default_ascent = 0, font_encoder = 0x1000040800001008, driver =
0xdd5f60, encoding_charset = 1, repertory_charset = 1}
(gdb)

Here's the output.