Both the Nicosia and Cocoa ports duplicate code specific to making sticky nodes work in the scrolling tree. Instead, this code could be moved to a shared class.
Overflow and frame scrolling nodes also share a bit of code.
Created attachment 441056 [details]
Created attachment 441064 [details]
Created attachment 441117 [details]
Created attachment 442576 [details]
Committed r284920 (243591@main): <https://commits.webkit.org/243591@main>
All reviewed patches have been landed. Closing bug and clearing flags on attachment 442576 [details].