Before I can do anything with our non-standard 'symbol.ttf', I have
to register this font, otherwise CoreText (silently) returns font descriptor for
some arbitrary (well, algorithm is unknown) substitute font and obviously our
"trick" with code positions from private range fails.

Funny, on my Mac I was not able to reproduce the problem, since many years/many Mac OS versions ago I accidentally clicked on a symbol.ttf and _registered_ it. Even after I installed 10.6, 10.7, 10.8 this font is still registered
(tell me about evil Microsoft Windows :)).

Many thanks to Olivier for spotting the problem.


git-svn-id: https://root.cern.ch/svn/root/trunk@48266 27541ba8-7e3a-0410-8455-c3a389f83636