Created attachment 373416 [details]
Attached test case shows a bug with async scrolling where a content resize fails to scroll the scroller back to the top.
It does scroll to the top, but it fails to reposition non-paint-order composited descendants.
Created attachment 373453 [details]
Comment on attachment 373453 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=373453&action=review
> + Some layers inside overflow:scroll move back to correct positions when the contents are shrunk
Title needs fixing.