Stop using assert_throws() under LayoutTests/http/wpt since it has been dropped from testharness.js upstream, in favor of assert_throws_dom() / assert_throws_js() variants.
Created attachment 402611 [details] Patch
Committed r263438: <https://trac.webkit.org/changeset/263438> All reviewed patches have been landed. Closing bug and clearing flags on attachment 402611 [details].
<rdar://problem/64680117>