If the gconf var abbreviate_tab_names be changed, this method will
        be called and will update tab names.

def abbreviate_tab_names_changed(self, settings, key, user_data):
        """If the gconf var abbreviate_tab_names be changed, this method will
        be called and will update tab names.
        """
        abbreviate_tab_names = settings.get_boolean('abbreviate-tab-names')
        self.guake.abbreviate = abbreviate_tab_names
        self.guake.recompute_tabs_titles()