When tabbing: on Enter open the current submenu and close other submenus if open, see #19394

git-svn-id: http://svn.automattic.com/wordpress/trunk@19505 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/js/common.dev.js

@@ -229,6 +229,7 @@ $(document).ready( function() {
 		e.stopPropagation();
 		e.preventDefault();
 
+		menu.find('.wp-submenu').removeClass('sub-open');
 		target.siblings('.wp-submenu').toggleClass('sub-open').find('a[role="menuitem"]').each(refresh);
 	}).each(refresh);