Reduce flakiness of http_client_stays_alive_test.

tests/standalone/io/socket_ipv6_test.dart

Index: tests/standalone/io/socket_ipv6_test.dart
diff --git a/tests/standalone/io/socket_ipv6_test.dart b/tests/standalone/io/socket_ipv6_test.dart
index e3a2e9120e8417a862ce8ca31cabff3a9bb45194..54f8a5018b1ea478065c0653c4e44b94e6f4ffa2 100644
--- a/tests/standalone/io/socket_ipv6_test.dart
+++ b/tests/standalone/io/socket_ipv6_test.dart
@@ -124,12 +124,12 @@ void testIPv4toIPv6_IPV6Only() {
 }
 
 void main() {
-  testIPv6toIPv6();
-  testIPv4toIPv6();
-  testIPv6toIPv4();
-  testIPv4toIPv4();
-  testIPv6Lookup();
-  testIPv4Lookup();
+  testIPv6toIPv6();           /// none: ok

[Florian Schneider, 2016/12/12 21:05:14]

Unrelated, but seems good in general to split up tests like this into smaller
units.

+  testIPv4toIPv6();           /// 01: ok
+  testIPv6toIPv4();           /// 02: ok
+  testIPv4toIPv4();           /// 03: ok
+  testIPv6Lookup();           /// 04: ok
+  testIPv4Lookup();           /// 05: ok
 
-  testIPv4toIPv6_IPV6Only();
+  testIPv4toIPv6_IPV6Only();  /// 06: ok
 }