Bug 255434

Summary: [margin-trim] RenderBox should not be performing trimming
Product: WebKit Reporter: Sammy Gill <sgill26>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: bfulgham, simon.fraser, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   

Description Sammy Gill 2023-04-13 21:18:57 PDT 
RenderBox performs some trimming inside of constrainBlockMarginInAvailableSpaceOrTrim and computeOrTrimInlineMargin as the renderer goes through layout. This has some unfortunate side effects, such as requiring us to set the rare data bits to indicate the margin has been trimmed at the same location. This action requires a const_cast that could be avoided since trimming should not occur at the RenderBox level and should be occurring completely in the layout system it is in (flex, grid, or block). We should make sure that the trimming logic is contained wholly within each layout system and should remove this logic from RenderBox once it is
Comment 1 Radar WebKit Bug Importer 2023-04-13 21:19:14 PDT 
<rdar://problem/108030923>