Summary:
@public
`YGFloatOptional::getValue()` has the unfortunate property of calling `std::exit` if the wrapped value is undefined.
That forces `x.isUndefined() ? fallback : x.getValue()` as access pattern.
Here, we replace that by introducing `YGFloatOptional::orElse(float)` which encapsulates that pattern. Other additions are `orElseGet([] { … })` and some extra operators.
Reviewed By: SidharthGuglani
Differential Revision: D13209152
fbshipit-source-id: 4e5deceaaaaf8eaed44846a8c152cc8b235e815c
50ec35575f