RenderBox::applyVisualEffectOverflow() and RenderBox::outlineBoundsForRepaint() use different ways of computing outline/shadow extent

[Simon Fraser (smfr)]

RenderBox::applyVisualEffectOverflow() and RenderBox::outlineBoundsForRepaint() have different logic for combining outline/shadow extents, and give different answers on an element like:

        .box {
            margin: 30px;
            width: 50%;
            height: 500px;
            border: 12px solid gray;
            outline: 5px solid green;
            box-shadow: 0 0 0px 20px black;
        }

[Simon Fraser (smfr)]

RenderBox 0x138003430 outlineBoundsForRepaint - outline bounds (-25,-25) width=225 height=574 bigger than visual overflow (-20,-20) width=215 height=564

[Simon Fraser (smfr)]

These should give the same result:

    applyVisualEffectOverflow(borderBoxRect())

and

    LayoutRect box = borderBoundingBox();
    adjustRectForOutlineAndShadow(box);

[Radar WebKit Bug Importer]

<rdar://problem/118582062>

[Simon Fraser (smfr)]

Pull request: https://github.com/WebKit/WebKit/pull/20961

[EWS]

Committed 271254@main (6aa1f6767674): <https://commits.webkit.org/271254@main>

Reviewed commits have been landed. Closing PR #20961 and removing active labels.