Use cloned unhandledReasons array

This allows it be inspected in the dev tools even after it has been modified.

### Before

![screen shot 2014-02-05 at 11 05 57 am](https://f.cloud.github.com/assets/671378/2090768/ac64fefc-8e98-11e3-817d-81e89a107557.png)

### After

![screen shot 2014-02-05 at 11 06 16 am](https://f.cloud.github.com/assets/671378/2090771/b12fc57a-8e98-11e3-921d-4be3756db4eb.png)