change summary:
- added a new "InternalUseParam" UFUNCTION() meta to support tagging function parameters as internal use only (=> hidden | not connectable)
- added a UK2Node_CallFunction::IsConnectionDisallowed() override method; returns 'true' if the 'bNotConnectable' flag is set on the node's pin (and will emit a compile error in existing projects if something is connected to it)
- modified FBlueprintEditorUtils::GetHiddenPinsForFunction() to accept an optional 'InternalPins' TSet as an output; on return, this will contain the subset of hidden pins that are marked as "InternalUseParam"
- modified UK2Node_CallFunction::CreatePinsForFunctionCall() to set the 'bNotConnectable' pin attribute to 'true' if "InternalUseParam == '<PinName>'" is included within the UFunction metadata
- modified the AActor::AddComponent UFUNCTION() decl to switch the "HidePin" meta to "InternalUseParam" for the 'ComponentTemplateContext' parameter (because it should not be connectable)
- modified UK2Node_CallFunction::NotifyPinConnectionListChanged() to refresh the node to hide pins corresponding to internal-only params once the (invalid) connection in an existing project has been broken
#codereview Mike.Beach
[CL 2606203 by Phillip Kavan in Main branch]
f864e2455c