Summary:
`enum class` types do not provide default conversion to integers and reguire use typename before value names.
This must prevent bugs like the previous one where we used `Undefined` as a number value.
Reviewed By: fkgozali
Differential Revision: D7554548
fbshipit-source-id: b19379aae48c9aebe03043e08cf3acc712da3cb8
Summary: `Undefined` is actually equal `0` (becasuse it is `LayoutDirection::Undefined`), whereas `kFloatUndefined` is a magic huge number.
Reviewed By: fkgozali
Differential Revision: D7554550
fbshipit-source-id: 3ea37f0b8b6a59b4b0e00d205b75cd7252247d03