Decrements the reference count for the type corresponding to the
interface default vtable g_iface. If the type is dynamic, then
when no one is using the interface and all references have
been released, the finalize function for the interface's default
vtable (the class_finalize member of GTypeInfo) will be called.
Decrements the reference count for the type corresponding to the interface default vtable g_iface. If the type is dynamic, then when no one is using the interface and all references have been released, the finalize function for the interface's default vtable (the class_finalize member of GTypeInfo) will be called.