Info:
* Source: en:Kanthkot Fort
* Target: gu
* Envionment: CX2 on master, localhoost
Steps to reproduce:
1. Start an article (like example)
2. Translate some content.
3. Scroll till end to add new category. It fails with following console error:
```
TypeError: this.categoryWidget.getCategories is not a function
at CategoryInputWidget.ve.ui.MWCategoryInputWidget.getLookupMenuOptionsFromData (http://localhost/core/extensions/VisualEditor/modules/ve-mw/ui/widgets/ve.ui.MWCategoryInputWidget.js?8f79f:124:44)
at CategoryInputWidget.<anonymous> (http://localhost/core/resources/lib/oojs-ui/oojs-ui-widgets.js?106e3:877:15)
at mightThrow (http://localhost/core/load.php?debug=true&lang=en&modules=jquery%2Cmediawiki%7Cmediawiki.base&only=scripts&skin=vector&version=02igl38:3583:29)
at process (http://localhost/core/load.php?debug=true&lang=en&modules=jquery%2Cmediawiki%7Cmediawiki.base&only=scripts&skin=vector&version=02igl38:3651:12) undefined