Array inputs in Custom Events cause a compiler "note"

Array inputs in Custom Events cause a compiler "note". On compile, "NOTE" is added to the node, and this appears in the Compiler Results: "Info No value will be returned by reference. Parameter 'List'. Node: SendList"

Did NOT occur in 4.8.3. Reproduced in 4.9 binary and Main (CL 2675088)

1. Open any project
2. Create a new Actor Blueprint
3. Create a Custom Event
4. Add an input of any type
5. Make the input an array
6. Compile

Result:
A Note is added to the Custom Event, and this is in the Compiler Results:
No value will be returned by reference. Parameter 'NewParam'.