Revert "Remove Expect from core library."

tests/language/fauxverride_test.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.
 
-import "package:expect/expect.dart";
-
 // Test the semantics of static members mixed with instance members.
 
 // Following are relevant quotes from Dart Programming Language
 // Specification, Draft Version 0.10, June 7, 2012.
 
 // 7 Classes:
 
 // "It is a compile-time error if a class has an instance method and a
 // static member method with the same name."
 
@@ skipping 74 matching lines @@
   Expect.equals('sub', Sub.m());
   Expect.equals('super', Super.i);
   Expect.equals('sub', Sub.i);
   Expect.equals('super', Super.i2);
   Expect.equals('sub', Sub.i2());
   Expect.equals('super', new Super().instanceMethod());
   Expect.equals('sub', new Sub().instanceMethod());
   Expect.equals('super', new Super().instanceMethod2());
   Expect.equals('super', new Sub().instanceMethod2());
 }