Fixed location pref tests for iOS7 iOS8

@jlipps can you check if this fixes the test for you. There was instability cause by failed xcrun erase leaving the Simulator folder in a bad state. 

@Jonahss could you check the xcrun erase part, 500ms was not enough.


i think it'd be nice to have a comment here explaining what this does, like:

```js
// wait at least 2s for simctl to do its thing
```

also, there's a spacing issue.