Adding a Pass By-Reference input parameter to an event dispatcher is allowed, but causes a warning when called.

You can add a pass-by-reference input variable to an Event Dispatcher, but it will will result in compile warnings, and changes to that input will not affect the value of the variable in the caller.

1. Create a new Blueprint
2. Add an Event Dispatcher
3. Open the Event Dispatcher
4. Add an input parameter to the Event Dispatcher function, and tick 'Pass-By-Reference'
5. Go to the Event Graph (or any other graph) and add a call to the new Event Dispatcher.
6. Wire up the execution pin into the call (e.g. to Event BeginPlay)
7. Right-click on the input parameter and Promote to Variable
8. Compile the Blueprint

Results: Warning: "No value will be returned by reference."

Expected: The editor should not allow pass-by-reference parameters to be added to Event Dispatchers