throw error when checking for the index of a node that has no parent.

it probably isn't in the dom if this is the case.
Check if it's there before using this function

www/common/treesome.js

@@ -89,6 +89,7 @@ define([], function () {
     var indexOfNode = tree.indexOfNode = function (el) {
         if (!(el && el.parentNode)) {
             console.log("No parentNode found!");
+            throw new Error('No parentNode found!');
         }
         return Array.prototype.indexOf.call(el.parentNode.childNodes, el);
     };