Like we did for flexbox in bug 191460 let's update the WPT import of css-grid tests and deduplicate old layout tests in favor of WPT ones.
Created attachment 399933 [details] Patch test EWS, ignore
Created attachment 399964 [details] Patch test EWS, ignore
Created attachment 399977 [details] Patch test EWS, ignore.
Created attachment 400031 [details] Patch
Comment on attachment 400031 [details] Patch r? Asking for review now. All EWS green.
Committed r262056: <https://trac.webkit.org/changeset/262056> All reviewed patches have been landed. Closing bug and clearing flags on attachment 400031 [details].
<rdar://problem/63539293>