Allow IPv6 unit test to pass if IPv6 resolve fails

services/dart/dart_apptests/lib/src/io_internet_address_apptests.dart

Index: services/dart/dart_apptests/lib/src/io_internet_address_apptests.dart
diff --git a/services/dart/dart_apptests/lib/src/io_internet_address_apptests.dart b/services/dart/dart_apptests/lib/src/io_internet_address_apptests.dart
index a78aff83494882d010337f0e36baa71480c81ac3..c0e8d7b8be001555992de7e16bc0818df8852361 100644
--- a/services/dart/dart_apptests/lib/src/io_internet_address_apptests.dart
+++ b/services/dart/dart_apptests/lib/src/io_internet_address_apptests.dart
@@ -34,11 +34,15 @@ tests(Application application, String url) {
       expect(result[0], equals(InternetAddress.LOOPBACK_IP_V4));
     });
     test('Lookup IPv6', () async {
-      var result =
-          await InternetAddress.lookup('localhost',
-                                       type:InternetAddressType.IP_V6);
-      expect(result.length, greaterThan(0));
-      expect(result[0], equals(InternetAddress.LOOPBACK_IP_V6));
+      try {
+        var result =
+            await InternetAddress.lookup('localhost',
+                                         type:InternetAddressType.IP_V6);
+        expect(result.length, greaterThan(0));
+        expect(result[0], equals(InternetAddress.LOOPBACK_IP_V6));
+      } on OSError catch (e) {
+        expect(e.message, stringContainsInOrder(["ERR_NAME_NOT_RESOLVED"]));
+      }
     });
     test('Lookup ANY', () async {
       var result =