Using std::optional<unsigned> instead of UINT_MAX to indicate when there is no selected scroll offset will more easily prevent errors in the code.
<rdar://problem/79208115>
Created attachment 431423 [details] Patch
Created attachment 431432 [details] Patch
Committed r278923 (238854@main): <https://commits.webkit.org/238854@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 431432 [details].