Why GtkFontSelectionDialog doesn't implements GtkFontSelection?

[John Williams <asb1231 gmail com>]

Hi all,

I was reading the documentation of the GtkFontSelectionDialog and see
that it implements own methods to set and get the GtkFontSelection
properties. Why it is at this way? Isn't more correct and standard use
methods of GtkFontSelection just casting with GTK_FONT_SELECTION() the
font selection dialog?

Thank you.