Implemented by subclasses to return a custom version of the supplied error object that is more suitable for presentation in alert sheets and dialogs.
Original signature is '- (NSError *)willPresentError:(NSError *)anError'
Available in Mac OS X v10.4 and later.
- anError (NSError)
- The error object to be customized.
- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)