Private and Protected functions do not display in the context menu in child BPs

This was introduce by changes to UEdGraphSchema_K2::CanFunctionBeUsedInGraph in CL 9230757 for [Link Removed].

1. Create a blueprint (derived from actor), call it BP_Base
2. Right click it in the content browser and click 'Create Child Blueprint Class', call it BP_Child
3. Open BP_Child for editing
4. Add a function, call it MyPrivateFunction, and mark the access specifier as Private
5. Add a function, call it MyProtectedFunction, and mark the access specifier as Protected
6. Go to the event graph, drag an execution line from BeginPlay and type MyPr (with context sensitive on). Observe that both functions don't show up to be called. This is incorrect.