test: add test for https agent servername option

PR-URL: https://github.com/joyent/node/pull/9368
Reviewed-By: jasnell - James M Snell <jasnell@gmail.com>

test/simple/test-https-agent-servername.js

@@ -0,0 +1,40 @@
+var common = require('../common');
+var assert = require('assert');
+
+if (!common.hasCrypto) {
+  console.log('1..0 # Skipped: missing crypto');
+  process.exit();
+}
+
+var https = require('https');
+var fs = require('fs');
+
+var options = {
+  key: fs.readFileSync(common.fixturesDir + '/keys/agent1-key.pem'),
+  cert: fs.readFileSync(common.fixturesDir + '/keys/agent1-cert.pem'),
+  ca:  fs.readFileSync(common.fixturesDir + '/keys/ca1-cert.pem')
+};
+
+
+var server = https.Server(options, function(req, res) {
+  res.writeHead(200);
+  res.end('hello world\n');
+});
+
+
+server.listen(common.PORT, function() {
+  https.get({
+    path: '/',
+    port: common.PORT,
+    rejectUnauthorized: true,
+    servername: 'agent1',
+    ca: options.ca
+  }, function(res) {
+    res.resume();
+    console.log(res.statusCode);
+    server.close();
+  }).on('error', function(e) {
+    console.log(e.message);
+    process.exit(1);
+  });
+});