Apply object updates from the network without blowing away object identity or UI attributes.

Tools/GardeningServer/ui/test/ct-failure-stream-tests.html

 <!--
 Copyright 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 -->
 
 <link rel="import" href="../ct-failure-stream.html">
 
 <script>
 (function () {
 
 var assert = chai.assert;
 
 describe('ct-failure-stream', function() {
 
   var stream;
 
   beforeEach(function(done) {
     stream = document.createElement('ct-failure-stream');
     setTimeout(done);
   });
 
   describe('default ui', function() {
     it('should show failure groups', function(done) {
       // FIXME: We should use some more interesting test data, but
       // ct-failure-stream will give these values to ct-commit-data,
       // which will hit the network unless we figure out how to mock
       // out ct-commit-data in a better way.
-      stream.groups = [new CTFailureGroup([], undefined), new CTFailureGroup([], undefined)];
+      stream.groups = [new CTFailureGroup('', [], undefined),
+                       new CTFailureGroup('', [], undefined)];
       stream.category = 'default';
       setTimeout(function() {
         var cards = stream.shadowRoot.querySelectorAll('ct-failure-card');
         assert.equal(cards.length, 2);
         done();
       });
     });
   });
 
   describe('category', function() {
     it('should only show failure groups for the specified category', function(done) {
       var failures = [new CTFailure('step', 'reason', [{key: 'a', annotation: {snoozeTime: Date.now() + 1000 * 1000}}])];
-      var snoozed = new CTFailureGroup(failures, undefined);
-      stream.groups = [new CTFailureGroup([], undefined), snoozed];
+      var snoozed = new CTFailureGroup('', failures, undefined);
+      stream.groups = [new CTFailureGroup('', [], undefined), snoozed];
       stream.category = 'snoozed';
       setTimeout(function() {
         var cards = stream.shadowRoot.querySelectorAll('ct-failure-card');
         assert.equal(cards.length, 1);
         assert.equal(cards[0].group, snoozed);
         done();
       });
     });
   });
 });
 
 })();
 </script>