Turn off various preferences when in captive portal mode.
<rdar://84622396>
Created attachment 443841 [details] WIP Patch
Created attachment 443844 [details] WIP Patch
Created attachment 443850 [details] Patch
Created attachment 443852 [details] Patch
Comment on attachment 443852 [details] Patch r=me
Committed r285634 (244135@main): <https://commits.webkit.org/244135@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 443852 [details].