Initial version of mocking support. There is still quite a bit of

tests/lib/unittest/test_utils.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.
 
 int errorCount;
 String errorString;
 var _testHandler = null;
 
 class MyFailureHandler extends DefaultFailureHandler {
   void fail(String reason) {
     ++errorCount;
     errorString = reason;
   }
 }
 
 void initUtils() {
   if (_testHandler == null) {
     _testHandler = new MyFailureHandler();
   }
 }
 
 void shouldFail(value, Matcher matcher, expected) {
-  configureExpectHandler(_testHandler);
+  configureExpectFailureHandler(_testHandler);
   errorCount = 0;
   errorString = '';
   expect(value, matcher);
-  configureExpectHandler(null);
+  configureExpectFailureHandler(null);
   expect(errorCount, equals(1));
   if (expected is String) {
     expect(errorString, equalsIgnoringWhitespace(expected));
   } else {
    expect(errorString, expected);
   }
 }
 
 void shouldPass(value, Matcher matcher) {
-  configureExpectHandler(_testHandler);
+  configureExpectFailureHandler(_testHandler);
   errorCount = 0;
   errorString = '';
   expect(value, matcher);
-  configureExpectHandler(null);
+  configureExpectFailureHandler(null);
   expect(errorCount, equals(0));
 }