Hack fix to include Mock in the API documentation.

pkg/unittest/lib/unittest.dart

 // Copyright (c) 2011, 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.
 
 /**
  * A library for writing dart unit tests.
  *
  * To import this library, use the pub package manager.
  * Create a pubspec.yaml file in your project and add
  * a dependency on unittest with the following lines:
@@ skipping 133 matching lines @@
  *       });
  *     }
  *
  */
 library unittest;
 
 import 'dart:isolate';
 import 'matcher.dart';
 export 'matcher.dart';
 
+// TODO(amouravski): We should not need to import mock here, but it's necessary
+// to enable dartdoc on the mock library, as it's not picked up normally.
+import 'mock.dart';
+
 part 'src/config.dart';
 part 'src/test_case.dart';
 
 /** [Configuration] used by the unittest library. */
 Configuration _config = null;
 
 Configuration get config => _config;
 
 /**
  * Set the [Configuration] used by the unittest library. Returns any
@@ skipping 731 matching lines @@
 }
 
 /** Enable a test by ID. */
 void enableTest(int testId) => _setTestEnabledState(testId, true);
 
 /** Disable a test by ID. */
 void disableTest(int testId) => _setTestEnabledState(testId, false);
 
 /** Signature for a test function. */
 typedef void TestFunction();