This is currently called "rootContentsLayer" in the compositor and "scrolledContentsLayer" in the scrolling tree. We want to free term "scrolledContentsLayer" to mean the direct child layer of the scrollview layer.
Created attachment 360721 [details] patch
Created attachment 360722 [details] patch
Created attachment 360723 [details] patch
Comment on attachment 360723 [details] patch Clearing flags on attachment: 360723 Committed r240800: <https://trac.webkit.org/changeset/240800>
All reviewed patches have been landed. Closing bug.
<rdar://problem/47710199>