test: expand test coverage for url.js

Add url example with more than 255 characters in the hostname
of the url.

PR-URL: https://github.com/nodejs/node/pull/8976
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ilkka Myller <ilkka.myller@nodefield.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

 Conflicts:
	test/parallel/test-url.js

test/parallel/test-url.js

@@ -1189,6 +1189,17 @@ var formatTests = {
     search: '?foo=bar#1#2#3&abc=#4##5',
     query: {},
     pathname: '/'
+  },
+
+  // more than 255 characters in hostname which exceeds the limit
+  [`http://${'a'.repeat(255)}.com/node`]: {
+    href: 'http:///node',
+    protocol: 'http:',
+    slashes: true,
+    host: '',
+    hostname: '',
+    pathname: '/node',
+    path: '/node'
   }
 };
 for (const u in formatTests) {