Bug 183214

Summary: [GTK] compositing/video/poster.html: video bar inconsistently filled after 'canplaythrough'
Product: WebKit Reporter: Alicia Boya García <aboya>
Component: WebKitGTKAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: bugs-noreply
Priority: P2    
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   

Description Alicia Boya García 2018-02-28 09:45:27 PST
The following test has a ImageOnlyFailure flake:

compositing/video/poster.html

https://build.webkit.org/results/GTK%20Linux%2064-bit%20Release%20(Tests)/r229090%20(5649)/compositing/video/poster-diffs.html

It contains this code:

<video controls id="v" poster="../resources/simple_image.png"></video>
<script>
var v = document.getElementById("v");
if (window.testRunner) {
    testRunner.waitUntilDone();
    v.addEventListener("canplaythrough", function() {
        testRunner.notifyDone();
    });
}
v.setAttribute("src", findMediaFile("video", "../resources/video"));
</script>

The video poster looks perfectly fine, the problem is with the controls; particularly the bar.

notifyDone() is called after the "canplaythrough" event. At that point, enough video should be buffered for smooth playback, but most of the time when the screenshot is taken the bar is still empty.