gtk/gtk.go
func (v *ToolButton) SetIconWidget(iconWidget IWidget) {
	C.gtk_tool_button_set_icon_widget(v.native(), iconWidget.toWidget())
}
func (v *ToolButton) SetIconWidget(iconWidget IWidget) {
	C.gtk_tool_button_set_icon_widget(v.native(), iconWidget.toWidget())
}
// SetIconWidget is a wrapper around gtk_tool_button_set_icon_widget().