Fix typo in r33216

runtime/bin/builtin.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 builtin;
 import 'dart:io';
 import 'dart:async';
 // import 'root_library'; happens here from C Code
 
 // The root library (aka the script) is imported into this library. The
@@ skipping 187 matching lines @@
     _entryPointScript = scriptUri;
   } else {
     // Script does not have a scheme, assume that it is a path,
     // resolve it against the working directory.
     _entryPointScript = _workingDirectoryUri.resolve(scriptName);
   }
   _logResolution('# Resolved entry point to: $_entryPointScript');
   return _entryPointScript.toString();
 }
 
-const _DART_EXT 'dart-ext:';
+const _DART_EXT = 'dart-ext:';
 
 String _resolveUri(String base, String userString) {
   _logResolution('# Resolving: $userString from $base');
   var baseUri = Uri.parse(base);
   if (userString.startsWith(_DART_EXT)) {
     var uri = userString.substring(_DART_EXT.length);
     return '$_DART_EXT${baseUri.resolve(uri)}';
   } else {
     return '${baseUri.resolve(userString)}';
   }
@@ skipping 36 matching lines @@
 
     throw "URIs using the 'package:' scheme should look like "
           "'$right', not '$wrong'.";
   }
 
   var packageRoot = _packageRoot == null ?
                     _entryPointScript.resolve('packages/') :
                     _packageRoot;
   return _filePathFromUri(packageRoot.resolve(uri.path).toString());
 }