fixup! fix($sanitize): prevent clobbered elements from freezing the browser

Author: gkalpak

src/ngSanitize/sanitize.js

@@ -531,7 +531,7 @@ function $SanitizeProvider() {
   function getNonDescendant(propName, node) {
     // An element is clobbered if its `propName` property points to one of its descendants
     var nextNode = node[propName];
-    if (nodeContains.call(node, nextNode)) {
+    if (nextNode && nodeContains.call(node, nextNode)) {
       throw $sanitizeMinErr('elclob', 'Failed to sanitize html because the element is clobbered: {0}', node.outerHTML || node.outerText);
     }
     return nextNode;