gboolean gtk_widget_get_hexpand_set ( GtkWidget* widget )
gtk_widget_set_hexpand() has been used
to explicitly set the expand flag on this widget.
GtkWidget:hexpand property is set, then it
overrides any computed expand value based on child widgets.
hexpand is not set, then the expand value depends on
whether any children of the widget would like to expand.
There are few reasons to use this function, but it’s here for completeness and consistency.