Description: use a domain that is more likely invalid
 avoids test failures in unisolated builds
--- a/tornado/test/netutil_test.py
+++ b/tornado/test/netutil_test.py
@@ -60,7 +60,7 @@ class _ResolverTestMixin(object):
             return True  # Halt propagation.
 
         with ExceptionStackContext(handler):
-            self.resolver.resolve('an invalid domain', 80, callback=self.stop)
+            self.resolver.resolve('anasdas23dadasdasdasdi2n1validsdasdbwefrwfejnefsegfsdomain', 80, callback=self.stop)
 
         result = self.wait()
         self.assertIsInstance(result, Exception)
@@ -69,7 +69,7 @@ class _ResolverTestMixin(object):
     def test_future_interface_bad_host(self):
         self.skipOnCares()
         with self.assertRaises(Exception):
-            yield self.resolver.resolve('an invalid domain', 80,
+            yield self.resolver.resolve('ana8sdasdadasdasdas1d12invalidsdasdbwefrwfejnefsegfsdomain', 80,
                                         socket.AF_UNSPEC)