Re-apply "Remove unittest and matcher from the repo."

pkg/unittest/test/async_setup_teardown_test.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.
-
-library unittest.async_setup_teardown;
-
-import 'dart:async';
-
-import 'package:metatest/metatest.dart';
-import 'package:unittest/unittest.dart';
-
-void main() => initTests(_test);
-
-void _test(message) {
-  initMetatest(message);
-
-  expectTestsPass('good setup/good teardown', () {
-    setUp(() {
-      return new Future.value(0);
-    });
-    tearDown(() {
-      return new Future.value(0);
-    });
-    test('foo1', () {});
-  });
-
-  expectTestResults('good setup/bad teardown', () {
-    setUp(() {
-      return new Future.value(0);
-    });
-    tearDown(() {
-      return new Future.error("Failed to complete tearDown");
-    });
-    test('foo2', () {});
-  }, [{
-    'result': 'error',
-    'message': 'Teardown failed: Caught Failed to complete tearDown'
-  }]);
-
-  expectTestResults('bad setup/good teardown', () {
-    setUp(() {
-      return new Future.error("Failed to complete setUp");
-    });
-    tearDown(() {
-      return new Future.value(0);
-    });
-    test('foo3', () {});
-  }, [{
-    'result': 'error',
-    'message': 'Setup failed: Caught Failed to complete setUp'
-  }]);
-
-  expectTestResults('bad setup/bad teardown', () {
-    setUp(() {
-      return new Future.error("Failed to complete setUp");
-    });
-    tearDown(() {
-      return new Future.error("Failed to complete tearDown");
-    });
-    test('foo4', () {});
-  }, [{
-    'result': 'error',
-    'message': 'Setup failed: Caught Failed to complete setUp'
-  }]);
-}