OSX Unicode Coretext crash bug

[Alexander Thurgood]

I don't know whether we have this referenced in our BZ (where it would
be a NOTOURBUG), and I don't recall seeing a discussion on here about
it, but this bug also affects my master build and also LO 4.1.1.2 on OSX
10.8.4, at least in Writer.

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_PROTECTION_FAILURE at address: 0x000000010c100000
0x00007fff91336adb in vDSP_sveD ()

How to reproduce :
Open a new Writer document.
Paste in the offending string of unicode characters.
Now attempt to move the cursor along the string - crash.

I guess we're dependent on Apple fixing their own mess in CoreText, but
in the meantime, this is a way to bring down LO (e.g. by sending someone
a document containing the string), at least on OSX 10.8.


Alex