2006-11-16  Michael Natterer  <mitch@imendio.com>

	Add new infrastructure for notifications of failed keyboard
	navigation and navigation with restricted set of keys.

	The patch handles configurable beeping, navigating the GUI with
	cursor keys only (as in phone environments), and configurable
	wrap-around. Fixes bugs #322640, #70986, #318827, #334726, #334742
	and #309291.

	* gtk/gtksettings.c: added properties gtk-keynav-cursor-only,
	gtk-keynav-wrap-around and gtk-error-bell.

	* gtk/gtkwidget.[ch]: added new signal "keynav-failed" and public
	API to emit it. Added New function gtk_widget_error_bell() which
	looks at the gtk-error-bell setting and calls gdk_window_beep()
	accordingly.

	* gtk/gtk.symbols: add the new widget symbols.

	* gtk/gtkcellrendereraccel.c
	* gtk/gtkimcontextsimple.c
	* gtk/gtkmenu.c
	* gtk/gtknotebook.c: use gtk_widget_error_bell() or look at the
	gtk-error-bell setting instead of calling gdk_display_beep()
	unconditionally.

	* gtk/gtkcombobox.c
	* gtk/gtkentry.c
	* gtk/gtkiconview.c
	* gtk/gtklabel.c
	* gtk/gtkmenushell.c
	* gtk/gtkspinbutton.c
	* gtk/gtktextview.c
	* gtk/gtktreeview.c: call gtk_widget_error_bell() on failed keynav.

	* gtk/gtkentry.c
	* gtk/gtklabel.c
	* gtk/gtkrange.c
	* gtk/gtktextview.c: consult gtk_widget_keynav_failed() on failed
	cursor navigation and leave the widget if it returns FALSE.

	* gtk/gtkmenushell.c
	* gtk/gtknotebook.c: only wrap around if gtk-keynav-wrap-around
	is TRUE.

	* gtk/gtkradiobutton.c: ask gtk_widget_keynav_failed() to decide
	whether to to wrap-around, and don't select active items on cursor
	navigation if gtk-keynav-cursor-only is TRUE. Should look at
	gtk-keynav-wrap-around too, will look into that.