Remove unittest and matcher from the repo.

pkg/matcher/lib/src/description.dart

-// Copyright (c) 2012, 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 matcher.description;
-
-import 'interfaces.dart';
-import 'pretty_print.dart';
-
-/// The default implementation of [Description]. This should rarely need
-/// substitution, although conceivably it is a place where other languages
-/// could be supported.
-class StringDescription implements Description {
-  final StringBuffer _out = new StringBuffer();
-
-  /// Initialize the description with initial contents [init].
-  StringDescription([String init = '']) {
-    _out.write(init);
-  }
-
-  int get length => _out.length;
-
-  /// Get the description as a string.
-  String toString() => _out.toString();
-
-  /// Append [text] to the description.
-  Description add(String text) {
-    _out.write(text);
-    return this;
-  }
-
-  /// Change the value of the description.
-  Description replace(String text) {
-    _out.clear();
-    return add(text);
-  }
-
-  /// Appends a description of [value]. If it is an IMatcher use its
-  /// describe method; if it is a string use its literal value after
-  /// escaping any embedded control characters; otherwise use its
-  /// toString() value and wrap it in angular "quotes".
-  Description addDescriptionOf(value) {
-    if (value is Matcher) {
-      value.describe(this);
-    } else {
-      add(prettyPrint(value, maxLineLength: 80, maxItems: 25));
-    }
-    return this;
-  }
-
-  /// Append an [Iterable] [list] of objects to the description, using the
-  /// specified [separator] and framing the list with [start]
-  /// and [end].
-  Description addAll(String start, String separator, String end,
-                       Iterable list) {
-    var separate = false;
-    add(start);
-    for (var item in list) {
-      if (separate) {
-        add(separator);
-      }
-      addDescriptionOf(item);
-      separate = true;
-    }
-    add(end);
-    return this;
-  }
-}