anchor.diff:  
       _server.stdin.writeln('compile $scriptFilename');
   
  -    return stdoutHandler.compilerOutput.future;
  +    return _stdoutHandler.compilerOutput.future;
     }
   
     Future<CompilerOutput> compileExpression(String expression, List<String> definitions,
         List<String> typeDefinitions, String libraryUri, String klass, bool isStatic) {
  -    stdoutHandler.reset();
  +    _stdoutHandler.reset();
   
       // 'compile-expression' should be invoked after compiler has been started,
       // program was compiled.
  
positive.code:       _packagesPath = packagesPath,
        _fileSystemRoots = fileSystemRoots,
        _fileSystemScheme = fileSystemScheme,
        stdoutHandler = new _StdoutHandler(consumer: compilerMessageConsumer) {
      // This is a URI, not a file path, so the forward slash is correct even on Windows.
      if (!_sdkRoot.endsWith('/'))
        _sdkRoot = '$_sdkRoot/';
  
negative.code:   final String _fileSystemScheme;
    String _sdkRoot;
    Process _server;
    final _StdoutHandler _stdoutHandler;
  
    /// If invoked for the first time, it compiles Dart script identified by
    /// [mainPath], [invalidatedFiles] list is ignored.
  