This WPT test used to fail because its assertions which were failing included multipart/form-data payloads, which have a random boundary string. Those assertions are now succeeding since bug 227718.
Correction: the expectation file doesn't match the test's output, but it can be updated to match it since the output is no longer random.
Created attachment 445470 [details] Patch
Committed r286362 (244721@main): <https://commits.webkit.org/244721@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 445470 [details].
<rdar://problem/85921634>