Add built-in root certificates to dart:io SecureSocket.

tests/standalone/io/secure_builtin_roots_test.dart

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import "dart:io";
+import "dart:uri";
+import "dart:isolate";
+
+void testGoogleUrl() {
+  HttpClient client = new HttpClient();
+
+  void testUrl(String url) {
+    var requestUri = new Uri.fromString(url);
+    var conn = client.getUrl(requestUri);
+
+    conn.onRequest = (HttpClientRequest request) {
+      request.outputStream.close();
+    };
+    conn.onResponse = (HttpClientResponse response) {
+      Expect.isTrue(response.statusCode < 500);
+      Expect.isTrue(response.statusCode != 404);
+      response.inputStream.onData = () {
+        response.inputStream.read();
+      };
+      response.inputStream.onClosed = () {
+        client.shutdown();
+      };
+    };
+    conn.onError = (error) => Expect.fail("Unexpected IO error $error");
+  }
+
+  testUrl('https://www.google.com');
+}
+
+void InitializeSSL() {
+  SecureSocket.initialize();
+}
+
+void main() {
+  InitializeSSL();
+  testGoogleUrl();
+}