Migrate test block 30 + corelib portion of block 31 to Dart 2.0.

tests/corelib_strong/unicode2_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.
-
-import 'package:expect/expect.dart';
-
-const String testPhrase = "The quick brown fox jumps over the lazy dog.";
-
-const List<int> testCodepoints = const <int>[
-  84,
-  104,
-  101,
-  32,
-  113,
-  117,
-  105,
-  99,
-  107,
-  32,
-  98,
-  114,
-  111,
-  119,
-  110,
-  32,
-  102,
-  111,
-  120,
-  32,
-  106,
-  117,
-  109,
-  112,
-  115,
-  32,
-  111,
-  118,
-  101,
-  114,
-  32,
-  116,
-  104,
-  101,
-  32,
-  108,
-  97,
-  122,
-  121,
-  32,
-  100,
-  111,
-  103,
-  46
-];
-
-main() {
-  testCodepointsToString();
-  testStringCharCodes();
-  testEmptyStringFromCharCodes();
-  testEmptyStringCharCodes();
-}
-
-void testStringCharCodes() {
-  Expect.listEquals(testCodepoints, testPhrase.codeUnits);
-}
-
-void testCodepointsToString() {
-  Expect.stringEquals(testPhrase, new String.fromCharCodes(testCodepoints));
-}
-
-void testEmptyStringFromCharCodes() {
-  Expect.stringEquals("", new String.fromCharCodes(<int>[]));
-}
-
-void testEmptyStringCharCodes() {
-  Expect.listEquals([], "".codeUnits);
-}