Properly refactored variables.

app/js/common/Utils.js

     // https://stackoverflow.com/questions/384286/javascript-isdom-how-do-you-check-if-a-javascript-object-is-a-dom-object
     try {
       // Using W3 DOM2 (works for FF, Opera and Chrome)
-      return obj instanceof HTMLElement;
+      return el instanceof HTMLElement;
     } catch(e) {
       // Browsers not supporting W3 DOM2 don't have HTMLElement and
       // an exception is thrown and we end up here. Testing some
       // properties that all elements have (works on IE7)
-      return (typeof obj==="object") && 
-        (obj.nodeType===1) && 
-        (typeof obj.style === "object") &&
-        (typeof obj.ownerDocument ==="object");
+      return (typeof(el) === "object") && 
+        (el.nodeType === 1) && 
+        (typeof(el.style) === "object") &&
+        (typeof(el.ownerDocument) === "object");
       }
   },