Update utils to new library syntax.

utils/tests/string_encoding/unicode_core_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_core_tests");
-#import("dunit.dart");
-#import("../../string_encoding/unicode_core.dart");
+library unicode_core_tests;
+import 'dunit.dart';
+import '../../string_encoding/unicode_core.dart';
 
 void main() {
   TestSuite suite = new TestSuite();
   suite.registerTestClass(new UnicodeCoreTests());
   suite.run();
 }
 
 class UnicodeCoreTests extends TestClass {
   void registerTests(TestSuite suite) {
     register("testPlatform", testPlatform, suite);
@@ skipping 77 matching lines @@
         "d800 dbff last byte missing");
 
     // impossible bytes
     Expect.listEquals([0xfffd], utf16CodeUnitsToCodepoints([0x110000]),
         "110000 out of bounds");
 
     // overlong sequences not possible in utf16 (nothing < x10000)
     // illegal code positions d800-dfff not encodable (< x10000)
   }
 }