Implements secure sockets on Mac OS with SecureTransport API

tests/standalone/io/https_bad_certificate_test.dart

Index: tests/standalone/io/https_bad_certificate_test.dart
diff --git a/tests/standalone/io/https_bad_certificate_test.dart b/tests/standalone/io/https_bad_certificate_test.dart
index 90c630f693a954228a67f9732f08b45ef39197fd..7dc5aa2081c45ee72d35d5fb6cff3473d9fca9f5 100644
--- a/tests/standalone/io/https_bad_certificate_test.dart
+++ b/tests/standalone/io/https_bad_certificate_test.dart
@@ -57,8 +57,8 @@ Future runClient(int port,
                  result) async {
   HttpClient client = new HttpClient(context: context);
   client.badCertificateCallback = (X509Certificate certificate, host, port) {
-    Expect.equals('/CN=rootauthority', certificate.subject);
-    Expect.equals('/CN=rootauthority', certificate.issuer);
+    Expect.isTrue(certificate.subject.contains('rootauthority'));
+    Expect.isTrue(certificate.issuer.contains('rootauthority'));
     // Throw exception if one is requested.
     if (callbackReturns == 'exception') throw new CustomException();
     return callbackReturns;