Bug 246002

Summary:	Fix calculation of SeenFixedContainingBlockLayer in RenderLayer::flagsForUpdateLayerPositions
Product:	WebKit	Reporter:	Frédéric Wang (:fredw) <fred.wang>
Component:	Scrolling	Assignee:	Frédéric Wang (:fredw) <fred.wang>
Status:	RESOLVED FIXED
Severity:	Normal	CC:	simon.fraser, webkit-bug-importer
Priority:	P2	Keywords:	InRadar
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified

Description Frédéric Wang (:fredw) 2022-10-03 21:16:52 PDT

In  https://commits.webkit.org/253809@main, both RenderLayer::recursiveUpdateLayerPositions and RenderLayer::flagsForUpdateLayerPositions check RenderElement::canContainFixedPositionObjects() to decide whether to add the SeenFixedContainingBlockLayer flag, but this function always render true for RenderView. RenderLayer::recursiveUpdateLayerPositions excludes that case while RenderLayer::flagsForUpdateLayerPositions does not, they should be made consistent.

Comment 1 Frédéric Wang (:fredw) 2022-10-03 21:25:06 PDT

Pull request: https://github.com/WebKit/WebKit/pull/4964

Comment 2 EWS 2022-10-04 01:29:36 PDT

Committed 255114@main (a945e2b05441): <https://commits.webkit.org/255114@main>

Reviewed commits have been landed. Closing PR #4964 and removing active labels.

Comment 3 Radar WebKit Bug Importer 2022-10-04 01:30:19 PDT

<rdar://problem/100752757>