Remove old #import, #source, and #library syntax from tests/standalone.

tests/standalone/io/socket_many_connections_test.dart

Index: tests/standalone/io/socket_many_connections_test.dart
diff --git a/tests/standalone/io/socket_many_connections_test.dart b/tests/standalone/io/socket_many_connections_test.dart
index 7c3fd6a97a01f2dc4433fe449e5e8a76d3216bb6..6e718f90c0100d4a4dc284aa48f3400220ce014e 100644
--- a/tests/standalone/io/socket_many_connections_test.dart
+++ b/tests/standalone/io/socket_many_connections_test.dart
@@ -3,10 +3,11 @@
 // BSD-style license that can be found in the LICENSE file.
 //
 // Test creating a large number of socket connections.
+library ServerTest;
 
-#import("dart:io");
-#import("dart:isolate");
-#source("testing_server.dart");
+import "dart:io";
+import "dart:isolate";
+part "testing_server.dart";
 
 const CONNECTIONS = 200;