void gtk_widget_class_add_shortcut ( WidgetClass* self )
Installs a shortcut in
Every instance created for
widget_class or its subclasses will
inherit this shortcut and trigger it.
Shortcuts added this way will be triggered in the
phase, which means they may also trigger if child widgets have focus.
This function must only be used in class initialization functions otherwise it is not guaranteed that the shortcut will be installed.