Replace the existing unittest APIs with the new runner infrastructure.

lib/html_individual_config.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-/// A unit test library for running groups of tests in a browser, instead of the
-/// entire test file. This is especially used for large tests files that have
-/// many subtests, so we can mark groups as failing at a finer granularity than
-/// the entire test file.
-///
-/// To use, import this file, and call [useHtmlIndividualConfiguration] at the
-/// start of your set sequence. Important constraint: your group descriptions
-/// MUST NOT contain spaces.
 library unittest.html_individual_config;
 
-import 'dart:html';
-import 'unittest.dart' as unittest;
-import 'html_config.dart' as htmlconfig;
+import 'html_config.dart';
 
-class HtmlIndividualConfiguration extends htmlconfig.HtmlConfiguration {
+/// This is a stub class used to preserve compatibility with unittest 0.11.*.
+///
+/// It will be removed before the next version is released.
+@deprecated
+class HtmlIndividualConfiguration extends HtmlConfiguration {
   HtmlIndividualConfiguration(bool isLayoutTest) : super(isLayoutTest);
-
-  void onStart() {
-    var search = window.location.search;
-    if (search != '') {
-      var groups = search
-          .substring(1)
-          .split('&')
-          .where((p) => p.startsWith('group='))
-          .toList();
-
-      if (!groups.isEmpty) {
-        if (groups.length > 1) {
-          throw new ArgumentError('More than one "group" parameter provided.');
-        }
-
-        var testGroupName = groups.single.split('=')[1];
-        var startsWith = "$testGroupName${unittest.groupSep}";
-        unittest.filterTests(
-            (unittest.TestCase tc) => tc.description.startsWith(startsWith));
-      }
-    }
-    super.onStart();
-  }
 }
 
-void useHtmlIndividualConfiguration([bool isLayoutTest = false]) {
-  unittest.unittestConfiguration =
-      isLayoutTest ? _singletonLayout : _singletonNotLayout;
-}
-
-final _singletonLayout = new HtmlIndividualConfiguration(true);
-final _singletonNotLayout = new HtmlIndividualConfiguration(false);
+@deprecated
+void useHtmlIndividualConfiguration([bool isLayoutTest]) {}