Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1525
Accidentally left this inconsistent with some of the refactoring. Rename the lone usage of `Length` within Style class to `Style::Length` to match the rest of the code.
This is functionally identical as before.
Changelog: [Internal]
bypass-github-export-checks
Reviewed By: yungsters
Differential Revision: D52096820
fbshipit-source-id: d6c569a02fb27a6e7548a9c12ff764afb823a282