pkg/(unit)test: include a copy of old matcher

lib/unittest.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;
 
 import 'dart:async';
 import 'dart:collection';
 
-import 'package:matcher/matcher.dart' show TestFailure, wrapAsync;
-
 import 'src/configuration.dart';
 import 'src/expected_function.dart';
 import 'src/group_context.dart';
 import 'src/internal_test_case.dart';
+import 'src/matcher.dart' show TestFailure, wrapAsync;
 import 'src/test_case.dart';
 import 'src/test_environment.dart';
 
-export 'package:matcher/matcher.dart';
-
 export 'src/configuration.dart';
+export 'src/matcher.dart';
 export 'src/simple_configuration.dart';
 export 'src/test_case.dart';
 
 /// The signature for a function passed to [test].
 typedef dynamic TestFunction();
 
 /// [Configuration] used by the unittest library.
 ///
 /// Note that if a configuration has not been set, calling this getter will
 /// create a default configuration.
@@ skipping 401 matching lines @@
 /// Creates a test environment running in its own zone scope.
 ///
 /// This allows for multiple invocations of the unittest library in the same
 /// application instance. This is useful when, for example, creating a test
 /// runner application which needs to create a new pristine test environment on
 /// each invocation to run a given set of tests.
 withTestEnvironment(callback()) {
   return runZoned(callback,
       zoneValues: {#unittest.environment: new TestEnvironment()});
 }