dart:io | Add test for HttpClient requests that never complete their future.

tests/standalone/io/https_bad_certificate_client.dart

Index: tests/standalone/io/https_bad_certificate_client.dart
diff --git a/tests/standalone/io/https_bad_certificate_client.dart b/tests/standalone/io/https_bad_certificate_client.dart
index da160ed0b6984af209d3954d3996c24b48c2cd36..4fe59a95b61d939b050ff698ad7943cd22d3eefc 100644
--- a/tests/standalone/io/https_bad_certificate_client.dart
+++ b/tests/standalone/io/https_bad_certificate_client.dart
@@ -47,7 +47,7 @@ Future runHttpClient(int port, result) {
     }));
 
   client.badCertificateCallback = badCertificateCallback;
-  testFutures.add( client.getUrl(Uri.parse('https://$HOST_NAME:$port/$result'))
+  testFutures.add(client.getUrl(Uri.parse('https://$HOST_NAME:$port/$result'))
     .then((HttpClientRequest request) {
       expect(result == 'true');
       request.close().then((result) { });