Move unicode tests to utf package.

utils/tests/string_encoding/unicode_test.dart

-#!/usr/bin/env 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.
-
-library unicode_tests;
-import 'dunit.dart';
-
-void main() {
-  TestSuite suite = new TestSuite();
-  suite.registerTestClass(new UnicodeTests());
-  suite.run();
-}
-
-class UnicodeTests extends TestClass {
-  static const String testPhrase =
-      "The quick brown fox jumps over the lazy dog.";
-
-  static 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];
-
-  void registerTests(TestSuite suite) {
-    register("testCodepointsToString", testCodepointsToString, suite);
-    register("testStringCharCodes", testStringCharCodes, suite);
-    register("testEmptyStringFromCharCodes", testEmptyStringFromCharCodes, suite);
-    register("testEmptyStringCharCodes", testEmptyStringCharCodes, suite);
-  }
-
-  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);
-  }
-}