- Properly load the core libraries as libraries and not as scripts.

sdk/lib/utf/utf_sources.gypi

 # 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.
 
 # This file contains all sources for the dart:utf library.
 #
 # TODO(ager): When the VM can use the #source directive for libraries.
 # At that point utf.dart should be the only utf library file.
 {
   'sources': [
+    'utf.dart',
+    # The above file contains the parts listed below.
     'utf_core.dart',
     'utf_stream.dart',
     'utf8.dart',
     'utf16.dart',
     'utf32.dart',
   ],
 }