Group similar failures (same directory, same fixture)

Tools/GardeningServer/model/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 () {
+
+module("ct-failure");
+
+test("basic", 3, function() {
+  var tests = [
+    {
+      failure: new CTFailure('browser_tests', 'FooTest.Bar', {}, 123, 123),
+      expectedGroupName: 'FooTest'
+    },
+    {
+      failure: new CTFailure('webkit_tests', 'fast/text/foo.html', {}, 123, 123),
+      expectedGroupName: 'fast/text'
+    },
+    {
+      failure: new CTFailure('compile', undefined, {}, 123, 123),
+      expectedGroupName: undefined
+    }
+  ];
+  tests.forEach(function(test) {
+    equal(test.failure.reasonGroupName(), test.expectedGroupName);
+  }.bind(this));
+});
+
+})();
+</script>