Ember array methods

I'm seeing, `filterBy is not a function`, which is used in the application controller _outside_ the main class scope:

```javascript
const {
defaultLayerGroupState,
} = config;

const defaultLayerGroups = defaultLayerGroupState.filterBy('visible').mapBy('id').sort();

export default class ApplicationController extends Controller
```

Are ember array prototype extensions not supported? I'm guessing [this](https://github.com/ember-fastboot/fastboot/issues/170) is the relevant issue?