REGRESSION (r252161): Incorrect rendering of some inset box-shadow with spread and border-radius

[Antoine Quint]

Created attachment 398657 [details]
Testcase

See the attached test case which consists of:

<style>

div {
    width: 100px;
    height: 30px;

    box-shadow: rgb(0, 0, 0) 0px 0px 0px 1px inset;

    border-radius: 100px;

    /* Slowed down from 0.1s in original content */
    transition: box-shadow 1s linear;
}

div:hover {
    box-shadow: inset 0 0 0 2px #000;
}

</style>
<div></div>

Hovering the <div> shows an unpleasant behavior. This used to work fine before regressing in to r252161 and this was then improved a bit in r252689.

[Antoine Quint]

<rdar://problem/62570229>

[Simon Fraser (smfr)]

Created attachment 398662 [details]
Go big or go home

[Simon Fraser (smfr)]

Created attachment 398669 [details]
Static testcase

[Simon Fraser (smfr)]

Everything looks OK from the drawing side; we do the same drawing:

applying 2  (save)
applying 3  (clip-path (path move to (318,60), add line to (318,60), add curve to (318,87.61) (295.61,110) (268,110), add line to (68,110), add curve to (40.39,110) (18,87.61) (18,60), add line to (18,60), add curve to (18,32.39) (40.39,10) (68,10), add line to (268,10), add curve to (295.61,10) (318,32.39) (318,60), close subpath) (wind-rule EVEN-ODD))
applying 4  (translate (x 661.00) (y 0.00))
applying 5  (set-state (change-flags 512) (shadow-blur 0.00) (shadow-offset width=-661 height=0) (shadows-use-legacy-radius 0))
applying 6  (fill-rect-with-rounded-hole (extent (18,10) width=300 height=100) (rect (18,10) width=300 height=100) (rounded-hole-rect 48.00 40.00 240.00 40.00
topLeft=20.03 20.03
topRight=20.03 20.03
bottomLeft=20.03 20.03
bottomRight=20.03 20.03) (color #000000))
applying 7  (restore)

[Simon Fraser (smfr)]

Ah we're giving CG a non-renderable around hole rect:

applying 12  (fill-rect-with-rounded-hole (extent (18,120) width=300 height=100) (rect (18,120) width=300 height=100) (rounded-hole-rect 48.00 150.00 240.00 40.00
topLeft=20.23 20.23
topRight=20.23 20.23
bottomLeft=20.23 20.23
bottomRight=20.23 20.23) (color #000000))

[Simon Fraser (smfr)]

Created attachment 398705 [details]
Patch

[Simon Fraser (smfr)]

Created attachment 398754 [details]
For Windows EWS

[Simon Fraser (smfr)]

Created attachment 398769 [details]
For EWS

[Simon Fraser (smfr)]

Created attachment 398784 [details]
For EWS

[EWS]

Committed r261334: <https://trac.webkit.org/changeset/261334>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 398784 [details].