[webkit-reviews] review requested: [Bug 80744] [chromium] Threaded opacity animation jump to opacity of 0 : [Attachment 132080] Patch

[bugzilla-daemon at webkit.org]

vollick at chromium.org has asked	for review:
Bug 80744: [chromium] Threaded opacity animation jump to opacity of 0
https://bugs.webkit.org/show_bug.cgi?id=80744

Attachment 132080: Patch
https://bugs.webkit.org/attachment.cgi?id=132080&action=review

------- Additional Comments from vollick at chromium.org
(In reply to comment #13)
> (From update of attachment 131843 [details])
> View in context:
https://bugs.webkit.org/attachment.cgi?id=131843&action=review
>
> > Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHostCommon.cpp:115
> > +static bool subtreeShouldBeSkipped(LayerType* layer, float drawOpacity)
>
> I think this is wrong for impl-side since we calculate this for every frame.
If on the impl side a layer has opacity == 0 on a given frame then we
definitely can and should skip it, even if there's an active animation, because
we'll redo the calculation on the next frame.  On the main thread side I think
we shouldn't skip the subtree if there is an animation active since we don't
run through this code for every frame.
>
> You could specialize this for the two layer types to get divergent behavior.

Done.

I've also removed the crasher fix.