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

Tools/GardeningServer/model/test/ct-failure-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.html">
 
 <script>
 (function () {
 
 var assert = chai.assert;
 
 describe('ct-failure model', function() {
   var tests = [
     {
       failure: new CTFailure('browser_tests', 'FooTest.Bar', {}, 123, 123),
-      expectedGroupName: 'FooTest'
+      expectedGroupName: 'FooTest',
+      expectedFingerprint: 'browser_tests::FooTest.Bar',
     },
     {
       failure: new CTFailure('webkit_tests', 'fast/text/foo.html', {}, 123, 123),
-      expectedGroupName: 'fast/text'
+      expectedGroupName: 'fast/text',
+      expectedFingerprint: 'webkit_tests::fast/text/foo.html',
     },
     {
       failure: new CTFailure('compile', undefined, {}, 123, 123),
-      expectedGroupName: undefined
+      expectedGroupName: undefined,
+      expectedFingerprint: 'compile::undefined',
     }
   ];
   it('group name', function() {
     tests.forEach(function(test) {
       assert.equal(test.failure.reasonGroupName(), test.expectedGroupName);
     });
   });
+  it('has fingerprint', function() {
+    tests.forEach(function(test) {
+      assert.propertyVal(test.failure, 'fingerprint', test.expectedFingerprint);
+    });
+  });
 });
 
 })();
 </script>