MAGETWO-91504: Mobile PDP accordion widget hides accordion content on phones with iOS

- only scroll to element when element gets out of the viewport

Author: cpartica

lib/web/mage/collapsible.js

@@ -559,10 +559,11 @@ define([
         },
 
         /**
+         * @param {HTMLElement} elem
          * @private
          */
-        _isElementOutOfViewport: function (el) {
-            var rect = el.getBoundingClientRect();
+        _isElementOutOfViewport: function (elem) {
+            var rect = elem.getBoundingClientRect();
             return rect.bottom < 0 || rect.right < 0 || rect.left > window.innerWidth || rect.top > window.innerHeight;
         }
     });