Protect against StyleGetProperty exceptions
Protect against StyleGetProperty exceptions

This happens when the property is not set in the gtkrc,
which seems to be a fairly common case.

GNOME/hyena,dufoli/hyena,dufoli/hyena,petejohanson/hyena,petejohanson/hyena,GNOME/hyena,arfbtwn/hyena,arfbtwn/hyena