apparently the only difference between a non-floating float avoider (regular formatting context root) and a float box is that while float boxes intersect their margin box, simple float avoiders use their border box. We can do that without subclassing FloatAvoider.
Created attachment 401863 [details]
Comment on attachment 401863 [details]
Committed r263144: <https://trac.webkit.org/changeset/263144>
All reviewed patches have been landed. Closing bug and clearing flags on attachment 401863 [details].