Change of -webkit-overflow-scrolling causes a layout regardless of whether a stacking context was removed or added

• Component: Layout and Rendering
• Status: NEW ---

[Nick Maynard]

This bug: 
https://bugs.webkit.org/show_bug.cgi?id=120535

Adds a changeset to ensure that a layout is performed when the value of -webkit-overflow-scrolling changes, down to the creation/destruction of a stacking context.

In situations where the element has a stacking context for another reason (-webkit-transform, for example), there will already be a stacking context on the element.  Consequently, a change to -webkit-overflow-scrolling will have no effect on the existence of a stacking context.

In these cases, we see a visible flicker when the (unnecessary) layout is performed.

Perhaps a check to see if a layout is required based on the consequent creation/destruction of a stacking context would be more appropriate.

[Simon Fraser (smfr)]

(In reply to comment #0)
> In these cases, we see a visible flicker when the (unnecessary) layout is performed.

A layout which results in the same rendering should not cause a flicker.  What OS are you reporting this flicker on?