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

tests/standalone/io/socket_close_test.dart

Index: tests/standalone/io/socket_close_test.dart
diff --git a/tests/standalone/io/socket_close_test.dart b/tests/standalone/io/socket_close_test.dart
index f21abb77a8d29df83bf0403224819bb21940d053..6966a70770394133d24cd09178da8a70e2ddcd6a 100644
--- a/tests/standalone/io/socket_close_test.dart
+++ b/tests/standalone/io/socket_close_test.dart
@@ -27,7 +27,7 @@ class SocketClose {
         _errorEvents = 0,
         _iterations = 0 {
     _sendPort = spawnFunction(startSocketCloseServer);
-    start();
+    initialize();
   }
 
   void proceed() {
@@ -144,7 +144,7 @@ class SocketClose {
     _socket.onConnect = connectHandler;
   }
 
-  void start() {
+  void initialize() {
     _receivePort.receive((var message, SendPort replyTo) {
       _port = message;
       proceed();