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third_party/polymer/components/iron-selector/test/basic.html

Index: third_party/polymer/components/iron-selector/test/basic.html
diff --git a/third_party/polymer/components/iron-selector/test/basic.html b/third_party/polymer/components/iron-selector/test/basic.html
index 972421eba4501bc2cf4023ff21d1bc58dccf9804..08866bb35112f307cc2c314f0b9b5395ae36aeb1 100644
--- a/third_party/polymer/components/iron-selector/test/basic.html
+++ b/third_party/polymer/components/iron-selector/test/basic.html
@@ -196,8 +196,12 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 
           newItem.id = 'item999';
 
-          s2.addEventListener('iron-items-changed', function() {
+          s2.addEventListener('iron-items-changed', function(event) {
             changeCount++;
+            var mutation = event.detail;
+            assert.notEqual(mutation, undefined);
+            assert.notEqual(mutation.addedNodes, undefined);
+            assert.notEqual(mutation.removedNodes, undefined);
           });
 
           Polymer.dom(s2).appendChild(newItem);