Fix shadowing in tests. Constructor and method are not allowed to have

tests/standalone/io/echo_server_stream_test.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.
 //
 // Echo server test program to test socket streams.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
@@ skipping 10 matching lines @@
 
   EchoServerGame.start()
       : _receivePort = new ReceivePort(),
         _sendPort = null,
         _buffer = new List<int>(MSGSIZE),
         _messages = 0 {
     for (int i = 0; i < MSGSIZE; i++) {
       _buffer[i] = FIRSTCHAR + i;
     }
     _sendPort = spawnFunction(startEchoServer);
-    start();
+    initialize();
   }
 
   void sendData() {
 
     void errorHandler(Exception e) {
       Expect.fail("Socket error $e");
     }
 
     void connectHandler() {
 
@@ skipping 62 matching lines @@
     }
 
     _socket = new Socket(TestingServer.HOST, _port);
     if (_socket !== null) {
       _socket.onConnect = connectHandler;
     } else {
       Expect.fail("socket creation failed");
     }
   }
 
-  void start() {
+  void initialize() {
     _receivePort.receive((var message, SendPort replyTo) {
       _port = message;
       sendData();
     });
     _sendPort.send(TestingServer.INIT, _receivePort.toSendPort());
   }
 
   void shutdown() {
     _sendPort.send(TestingServer.SHUTDOWN, _receivePort.toSendPort());
     _receivePort.close();
@@ skipping 46 matching lines @@
 
     inputStream = connection.inputStream;
     inputStream.onData = dataReceived;
     connection.onError = errorHandler;
   }
 }
 
 main() {
   EchoServerGame echoServerGame = new EchoServerGame.start();
 }