Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1256
X-link: https://github.com/facebook/react-native/pull/37076
This adds a `YGErrata` bitset enum matching the API and guarantees described in https://github.com/facebook/yoga/issues/1247.
It is hooked up in later diffs. There are a couple of `YGExperimentalFeature` values that belong here, but keeping the current options means that the default `YGErrataNone` corresponds to existing default behavior, letting us stage the series of changes as:
1. Implement errata API
2. Update internal Yoga users we want to de-risk to `YGErrataClassic` or `YGErrataAll` (if setting `UseLegacyStretchBehaviour`)
3. Add new errata, changing Yoga defaults to be conformant, while letting internal apps opt into compatibility modes pending experimentation.
I also added a macro to let C++ users of Yoga perform bitwise operations on the enum without casting (already available for C users).
Reviewed By: rshest
Differential Revision: D45254098
fbshipit-source-id: 55cf5a0e0859a4ce17e3f3a6481a0afe549b6e55
