Make the repeating argument to timers optional.

samples/socket/SocketExample.dart

Index: samples/socket/SocketExample.dart
diff --git a/samples/socket/SocketExample.dart b/samples/socket/SocketExample.dart
index 5eed2e704e68b213a13cd7119e0e1902cb0d394c..66885d0427ae04991c1cdc79798a033b6d1440ee 100755
--- a/samples/socket/SocketExample.dart
+++ b/samples/socket/SocketExample.dart
@@ -46,14 +46,14 @@ class SocketExample {
     }
 
     // send next 4 bytes slowly
-    new Timer((Timer t) {
+    new Timer.repeating((Timer t) {
       sendByte();
       if (bytesSent == bytesTotal) {
         sendSocket.close();
         t.cancel();
         print("finished sending");
       }
-    }, 500, true );
+    }, 500);
   }
 
   void onConnect(Socket connection) {