Add testing resources from SkyDart branch

sky/tests/resources/third_party/matcher/matcher.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.
+
+/// Support for specifying test expectations, such as for unit tests.
+library matcher;
+
+export 'src/core_matchers.dart';
+export 'src/description.dart';
+export 'src/error_matchers.dart';
+export 'src/expect.dart';
+export 'src/future_matchers.dart';
+export 'src/interfaces.dart';
+export 'src/iterable_matchers.dart';
+export 'src/map_matchers.dart';
+export 'src/numeric_matchers.dart';
+export 'src/operator_matchers.dart';
+export 'src/prints_matcher.dart';
+export 'src/string_matchers.dart';
+export 'src/throws_matcher.dart';
+export 'src/throws_matchers.dart';
+export 'src/util.dart';