Promote WKPreferences._needsSiteSpecificQuirks to API
<rdar://83255206>
Created attachment 439096 [details] WIP patch
Created attachment 441127 [details] Patch
The two API test failures on api-gtk bot are not relevant to this patch.
Committed r284214 (243024@main): <https://commits.webkit.org/243024@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 441127 [details].