There is a 7th argument where one can specify some extra fields like nonInteractive described here :
https://developers.google.com/analytics/devguides/collection/analyticsjs/events
This framework wraps the ga method and exposes an event function that forwards the parameters only the first six, it would be nice if it could pass all the parameters that ga function supports.
The workaround ofcourse is to use the ga method directly from the global scope.