C++ 4.19 Transition Guide

If upgrading a project to 4.19 and your project uses FVariant (Runtime/Core/Public/Misc/Variant.h) be warned that EVariantTypes has finally been converted to a proper enum class (was previously a collection of namespace-scoped constants). Any switches using the GetType() on an instance of FVariant will need to be updated accordingly to handle an enum rather than int32 constants.