refactor(webapp): remove no-op function arg
refactor(webapp): remove no-op function arg

This was added in an attempt to silence an error/warning during debugging the upgrade to React 16,
but the fix was a red herring (something else was the matter).

opentripplanner/otp-react-redux,opentripplanner/otp-react-redux,opentripplanner/otp-react-redux,opentripplanner/otp-react-redux