The tests in http/tests/referrer-policy do not test all referrer-policy values.
Created attachment 363497 [details] Patch
Created attachment 363500 [details] Patch
I wonder how difficult it would be rely on WPT tests instead? Also, you should probably cc' a reviewer who is familiar with referrer-policy.
Comment on attachment 363500 [details] Patch Clearing flags on attachment: 363500 Committed r242531: <https://trac.webkit.org/changeset/242531>
All reviewed patches have been landed. Closing bug.
<rdar://problem/48630557>