Replace the existing unittest APIs with the new runner infrastructure.

test/async_exception_with_future_test.dart

-// Copyright (c) 2014, 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.
-
-library unittest.async_exception_with_future_test;
-
-import 'dart:async';
-
-import 'package:metatest/metatest.dart';
-import 'package:unittest/unittest.dart';
-
-void main() => initTests(_test);
-
-void _test(message) {
-  initMetatest(message);
-
-  expectTestResults('async exception with future test', () {
-    var tearDownHappened = false;
-
-    tearDown(() {
-      tearDownHappened = true;
-    });
-
-    test('test', () {
-      expect(tearDownHappened, isFalse);
-      // The "throw" statement below should terminate the test immediately.
-      // The framework should not wait for the future to complete.
-      // tearDown should still execute.
-      new Future.sync(() {
-        throw "error!";
-      });
-      return new Completer().future;
-    });
-
-    test('follow up', () {
-      expect(tearDownHappened, isTrue);
-    });
-  }, [
-    {'description': 'test', 'message': 'Caught error!', 'result': 'fail',},
-    {'description': 'follow up', 'result': 'pass',}
-  ]);
-}