Backdrop Filter should repaint when changed via script

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[Joseph Pecoraro]

* SUMMARY
Backdrop Filter should repaint when changed via script.

* TEST
<style>
.back {
    width: 300px;
    height: 150px;
    margin: 100px;
    background: blue;
}
.top {
    width: 1000px;
    height: 50px;
    position: absolute;
    left: 0;
    top: 150px;
    -webkit-backdrop-filter: blur(50px);
}
</style>
<div class="back">
    <div id="x" class="top"></div>
</div>

<button id="a">Blur 10</button>
<button id="b">Blur -10</button>
<button id="c">Blur 50</button>
<button id="d">Show / Hide the element</button>

<script>
a.onclick = function() { x.style.webkitBackdropFilter = "blur(10px)"; }
b.onclick = function() { x.style.webkitBackdropFilter = "blur(-10px)"; }
c.onclick = function() { x.style.webkitBackdropFilter = "blur(50px)"; }
d.onclick = function() { x.hidden = !x.hidden; }
</script>

* STEPS TO REPRODUCE
1. Show test
2. Click on one of the Blur buttons to change the blur
  => nothing happens, expected the element to repaint
3. Click the button to hide the blur element
3. Click the button to show the blur element
  => blur is now updated

[Radar WebKit Bug Importer]

<rdar://problem/22749892>

[Jon Lee]

*** Bug 155794 has been marked as a duplicate of this bug. ***

[Simon Fraser (smfr)]

Created attachment 275445 [details]
Testcase

[Simon Fraser (smfr)]

Created attachment 275446 [details]
Patch

[Simon Fraser (smfr)]

https://trac.webkit.org/r198963

[Joseph Pecoraro]

Nice!

[David Kilzer (:ddkilzer)]

(In reply to comment #5)
> https://trac.webkit.org/r198963

New test is failing on most bots:

<http://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=css3%2Ffilters%2Fbackdrop%2Fdynamic-backdrop-filter-change.html>

[David Kilzer (:ddkilzer)]

(In reply to comment #7)
> (In reply to comment #5)
> > https://trac.webkit.org/r198963
> 
> New test is failing on most bots:
> 
> <http://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=css3%2Ffilters%2Fbackdrop%2Fdynamic-backdrop-filter-change.html>

Tried to fix:

Committed r198971: <http://trac.webkit.org/r198971>