bug#21428: 24.5; Crash of emacs on OS X, installed via homebrew cask

[Eli Zaretskii <eliz@gnu.org>]

> From: Rainer M Krug <Rainer@krugs.de>
> Cc: 21428@debbugs.gnu.org,  mituharu+bug-gnu-emacs-mac@math.s.chiba-u.ac.jp
> Date: Wed, 23 Sep 2015 10:58:19 +0200
> 
> And here is the next one:
> 
> ,----
> | xdisp.c:24330: Emacs fatal error: assertion failed: face != NULL
> | Fatal error 6: Abort trap
> | Program received signal SIGABRT, Aborted.
> | 0x00007fff89f08c82 in __kill ()
> | (gdb) bt
> | #0  0x00007fff89f08c82 in __kill ()
> | #1  0x0000000100179390 in terminate_due_to_signal (sig=6, backtrace_limit=40) at emacs.c:397
> | #2  0x00000001001b0fe3 in emacs_abort () at sysdep.c:2219
> | #3  0x000000010033d2f8 in ns_term_shutdown (sig=6) at nsterm.m:4599
> | #4  0x0000000100179683 in shut_down_emacs (sig=6, stuff=0) at emacs.c:2038
> | #5  0x000000010017932b in terminate_due_to_signal (sig=6, backtrace_limit=2147483647) at emacs.c:381
> | #6  0x00000001002256eb in die (msg=0x1003b67ea "face != NULL", file=0x1003b24d0 "xdisp.c", line=24330) at alloc.c:6951
> | #7  0x0000000100063797 in get_glyph_face_and_encoding (f=0x1018371a0, glyph=0x11c8687e0, char2b=0x7fff5fbfb3e0) at xdisp.c:24330
> | #8  0x00000001000b5ffd in fill_glyph_string (s=0x7fff5fbfb410, face_id=44, start=10, end=30, overlaps=0) at xdisp.c:24555

Very similar to the previous one, except that there's no call to
debugger here.