Deprecation warning - datepicker

I have the following error in my Chrome console:

Deprecation warning: use moment.updateLocale(localeName, config) to change an existing locale. moment.defineLocale(localeName, config) should only be used for creating a new locale See http://momentjs.com/guides/#/warnings/define-locale/ for more info.

I have been searching for hours now, does anybody know how to remove/fix this error? It is related to datepicker.