Surprise :x

![screen shot 2014-10-13 at 09 28 12 am](https://cloud.githubusercontent.com/assets/154595/4613344/9ac6a1ae-52d4-11e4-8867-f1d846074564.png)


![screen shot 2014-10-13 at 09 27 41 am](https://cloud.githubusercontent.com/assets/154595/4613345/9c58bf5c-52d4-11e4-84fc-09e56ffbccd5.png)

This stub is not necessary any longer.
And if it is it should use the new syntax:
```ruby
allow(controller).to receive(:last_tweets).and_return([])
```