"There is an enum property of type 'ECollisionChannel' with an invalid value of '(INVALID)" warning when opening Level Blueprint

REGRESSION

Yes, does not occur in 4.14 at CL 3232073.

When opening the level blueprint, the user sees the following warning in the output log:

In asset 'None', there is an enum property of type 'ECollisionChannel' with an invalid value of '(INVALID)'

1. Open QAGame in editor.
2. Open the level blueprint.

RESULT

In the output log, a warning appears.

UE4Editor-CoreUObject.dll!UEnum::FindEnumIndex(FName InName) Line 436 C++
UE4Editor-BlueprintGraph.dll!UEdGraphSchema_K2::DefaultValueSimpleValidation(const FEdGraphPinType & PinType, const FString & PinName, const FString & NewDefaultValue, UObject * NewDefaultObject, const FText & InNewDefaultText, FString * OutMsg) Line 3961 C++
UE4Editor-BlueprintGraph.dll!UEdGraphSchema_K2::IsPinDefaultValid(const UEdGraphPin * Pin, const FString & NewDefaultValue, UObject * NewDefaultObject, const FText & InNewDefaultText) Line 2832 C++
> UE4Editor-BlueprintGraph.dll!UK2Node_MakeStruct::FMakeStructPinManager::CustomizePinData(UEdGraphPin * Pin, FName SourcePropertyName, int ArrayIndex, UProperty * Property) Line 104 C++
UE4Editor-BlueprintGraph.dll!FOptionalPinManager::CreateVisiblePins(TArray<FOptionalPinFromProperty,FDefaultAllocator> & Properties, UStruct * SourceStruct, EEdGraphPinDirection Direction, UK2Node * TargetNode, unsigned char * StructBasePtr) Line 1109 C++
UE4Editor-BlueprintGraph.dll!UK2Node_MakeStruct::AllocateDefaultPins() Line 162 C++
UE4Editor-BlueprintGraph.dll!UBlueprintNodeSpawner::Prime() Line 94 C++
UE4Editor-BlueprintGraph.dll!FBlueprintActionDatabase::Tick(float DeltaTime) Line 1097 C++
UE4Editor-UnrealEd.dll!FTickableEditorObject::TickObjects(float DeltaSeconds) Line 21 C++
UE4Editor-UnrealEd.dll!UEditorEngine::Tick(float DeltaSeconds, bool bIdleMode) Line 1397 C++
UE4Editor-UnrealEd.dll!UUnrealEdEngine::Tick(float DeltaSeconds, bool bIdleMode) Line 391 C++
UE4Editor.exe!FEngineLoop::Tick() Line 3019 C++
UE4Editor.exe!GuardedMain(const wchar_t * CmdLine, HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, int nCmdShow) Line 166 C++
UE4Editor.exe!WinMain(HINSTANCE__ * hInInstance, HINSTANCE__ * hPrevInstance, char * __formal, int nCmdShow) Line 195 C++
[External Code]