Make sure to process WebSocket frames when closing a WebSocket

tests/standalone/io/web_socket_pipe_test.dart

Index: tests/standalone/io/web_socket_pipe_test.dart
diff --git a/tests/standalone/io/web_socket_pipe_test.dart b/tests/standalone/io/web_socket_pipe_test.dart
index b487b7473bd6bc5aa7a4ccd69d65ac9d82e8ecf1..5439e8a9aafbee0212158040e7c7879adbc156f0 100644
--- a/tests/standalone/io/web_socket_pipe_test.dart
+++ b/tests/standalone/io/web_socket_pipe_test.dart
@@ -40,7 +40,6 @@ testPipe({int messages, bool transform}) {
         }
       }
 
-      next();
       client.listen(
           (data) {
             count++;
@@ -52,6 +51,8 @@ testPipe({int messages, bool transform}) {
             next();
           },
           onDone: () => print("Client received close"));
+
+      next();
     });
   });
 }