Fix Illegal invocation when accessing childNodes for pages including …

…Universal Viewer video #72197

src/polyfills/custom.js

@@ -79,7 +79,13 @@ if (!Element.prototype.closest) {
     constructor.prototype.children == null) {
     Object.defineProperty(constructor.prototype, 'children', {
       get: function() {
-        let i = 0, node, nodes = this.childNodes, children = [];
+	    let nodes = [];
+		try {
+		  nodes = this.childNodes;
+		} catch(error) {
+		  console.log(error);
+		}
+        let i = 0, node, children = [];
         while (node = nodes[i++]) {
           if (node.nodeType === 1) {
             children.push(node);