Update unittest to new package layout.

tests/isolate/message2_test.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.
 
 // Dart test program for testing serialization of messages.
 // VMOptions=--enable_type_checks --enable_asserts
 
 #library('Message2Test');
 #import("dart:isolate");
 
-#import('../../pkg/unittest/unittest.dart');
+#import('../../pkg/unittest/lib/unittest.dart');
 
 // ---------------------------------------------------------------------------
 // Message passing test 2.
 // ---------------------------------------------------------------------------
 
 class MessageTest {
   static void mapEqualsDeep(Map expected, Map actual) {
     Expect.equals(true, expected is Map);
     Expect.equals(true, actual is Map);
     Expect.equals(expected.length, actual.length);
@@ skipping 39 matching lines @@
     m[1] = "eins";
     m[2] = "deux";
     m[3] = "tre";
     m[4] = "four";
     remote.call(m).then(expectAsync1((var received) {
       MessageTest.mapEqualsDeep(m, received);
       remote.send(-1, null);
     }));
   });
 }