Import web-platform-tests/worklets tests from usptream.
Created attachment 414495 [details] Patch
Created attachment 414513 [details] Patch
Comment on attachment 414513 [details] Patch rs=me
Created attachment 414527 [details] Patch
Committed r270016: <https://trac.webkit.org/changeset/270016> All reviewed patches have been landed. Closing bug and clearing flags on attachment 414527 [details].
<rdar://problem/71573074>