Call OnFacename() for each font which supports given encoding (only if it is not wxFONTENCODING_SYSTEM) and is of fixed width (if fixedWidthOnly is true).
Call OnFacename() for each font which supports given encoding (only if it is not wxFONTENCODING_SYSTEM) and is of fixed width (if fixedWidthOnly is true).