CSSOMViewScrollingAPIEnabled should be on by default in WK1 and WK2.
Created attachment 374626 [details]
See my reply bug 182053 comment 37. I personally don't have any objection to enable this everywhere :-)
Comment on attachment 374626 [details]
Clearing flags on attachment: 374626
Committed r247708: <https://trac.webkit.org/changeset/247708>
All reviewed patches have been landed. Closing bug.