This is in preparation for the column span work
Created attachment 396208 [details] Patch
Created attachment 396220 [details] Patch
Created attachment 396222 [details] Patch
Committed r259981: <https://trac.webkit.org/changeset/259981> All reviewed patches have been landed. Closing bug and clearing flags on attachment 396222 [details].
<rdar://problem/61676609>
Filed: Bug 210592 – MSVC: LayoutUnits.h(248): warning C4245: 'argument': conversion from 'const int' to 'size_t', signed/unsigned mismatch