Reset to default arrow doesn't appear for BP Struct variables in Blueprints

When a variable of a struct is added to a blueprint, the reset to defaults arrow does not appear when the variable values and struct defaults differ.

Note:
A child of (or placed instance of) the blueprint will properly get the reset arrow when the struct variable values change.

Note2:
A code struct with values defined in the constructor will cause the arrow to appear when changed in a blueprint

Regression:
No - same behavior occurs in 4.16.3 (CL 3561208)

1. Open UE4 Editor (any project)
2. Right click in Content Browser and select Blueprints->Structure (StructBP)
3. Add String / Float / Boolean member variables
4. Save StructBP
5. Create a blueprint based on Actor (ActorBP)
6. Add a variable to the actor based on StructBP
7. Compile ActorBP
8. Change the defaults of StructBP variable

Result:
The yellow "reset to defaults" arrow does not appear giving no indication that the struct values have changed.

Expected:
Reset to defaults arrow appears when the variable values differ from the source struct value