Summary:
X-link: https://github.com/facebook/react-native/pull/46741
Pull Request resolved: https://github.com/facebook/yoga/pull/1711
box sizing is really just a reinterpretation of what length properties (like `width`, `height`, `max-width`, etc) mean. So to implement this I just add the border and padding if we are in content box when we ask for any of these properties. All the math that gets done by the algorithm is still in border box land, and the layout we return is to be interpreted as the border box (this is actually the expected behavior per https://drafts.csswg.org/css-sizing/#box-sizing). This makes this implementation pretty simple actually.
Changelog: [Internal]
Reviewed By: NickGerleman
Differential Revision: D63416833
fbshipit-source-id: fd76132cf51e8a5092129802c3a12ab24023018b