Fixed the long stack trace example (#349)

* The longStackTraceZoneSpec delegates the handling of the error to the parent zone. Without the changes I've made, the handling was passed to the 'root' zone which doesn't handle the error object. By adding a parentZone which handles the printing of the error in the 'onHandleError' hook, the full stack trace is visible.

* Fixed the formatting (back to before).

Author: KwintenP

Diff for: example/basic.html

@@ -46,8 +46,14 @@ <h1>Basic Example</h1>
    * Bootstrap the app
    */
   //main();
-  Zone.current.fork(Zone.longStackTraceZoneSpec).run(main);
+  Zone.current.fork(
+          {
+              onHandleError: function (parentZoneDelegate, currentZone, targetZone, error) {
+                  console.log(error.stack);
+              }
+          }
+  ).fork(Zone.longStackTraceZoneSpec).run(main);
 
   </script>
 </body>
-</html>
+</html>