divide by zero crash in mp4.c: MP4_TrackCreate()

Opening the attached file causes a crash, on 0.8.6e and on the latest git revision as of yesterday. Mac OS X 10.5.2 on a Mac Pro.

Program received signal EXC_ARITHMETIC, Arithmetic exception.
[Switching to process 1875 thread 0x6003]
0x9306531e in __udivdi3 ()
(gdb) bt
[#0](https://code.videolan.org/videolan/vlc/-/issues/0)  0x9306531e in __udivdi3 ()
[#1](https://code.videolan.org/videolan/vlc/-/issues/1)  0x027e8ec6 in MP4_TrackCreate (p_demux=0x4a6928, p_track=0x1206400, p_box_trak=0x4a6c70) at mp4.c:2040
[#2](https://code.videolan.org/videolan/vlc/-/issues/2)  0x027eb380 in Open (p_this=0x4a6928) at mp4.c:509
[#3](https://code.videolan.org/videolan/vlc/-/issues/3)  0x00161ffe in __module_Need (p_this=0x4a6928, psz_capability=0x18d83f "demux2", psz_name=0x19a4f7 "mp4", b_strict=0) at modules/modules.c:629
[#4](https://code.videolan.org/videolan/vlc/-/issues/4)  0x001102cd in __demux2_New (p_obj=0x4a4ad8, psz_access=0x18c4cc "", psz_demux=0x18c4cc "", psz_path=0x4a68a0 "00005035.mov", s=0x4a6728, out=0x4a61a0, b_quick=0) at input/demux.c:165
[#5](https://code.videolan.org/videolan/vlc/-/issues/5)  0x0011bf28 in InputSourceInit (p_input=0x4a4ad8, in=0x11dbe54, psz_mrl=0x4a43a0 "00005035.mov", psz_forced_demux=0x0) at input/input.c:2397
[#6](https://code.videolan.org/videolan/vlc/-/issues/6)  0x0011fbcd in Init (p_input=0x4a4ad8) at input/input.c:885
[#7](https://code.videolan.org/videolan/vlc/-/issues/7)  0x001222ad in Run (p_input=0x4a4ad8) at input/input.c:495
[#8](https://code.videolan.org/videolan/vlc/-/issues/8)  0x92902c55 in _pthread_start ()
[#9](https://code.videolan.org/videolan/vlc/-/issues/9)  0x92902b12 in thread_start ()