When toggling an element background from a color to a translucent gradient the gradient sometimes gets a black background.
This only appears to happen when will-change transform is enabled for the element.
1) View the example: https://codepen.io/jonastreub/pen/XwbWaR
2) Toggle the element background by clicking it
3) Notice that the gradient has a black background
Expected Results: The gradient to be translucent.
Sounds like we're failing to update contentsOpaque.
We currently re-evaluate contentsOpaque in RenderLayerBacking::updateGeometry(), but that doesn't fire for just a background change (repaint triggers an updateConfiguration()). However, contentsOpaque depends on geometry, and updateConfiguration() runs first, so I think we'll have to move it to updateAfterDescendants().
Created attachment 369658 [details]
Comment on attachment 369658 [details]
Clearing flags on attachment: 369658
Committed r245207: <https://trac.webkit.org/changeset/245207>
All reviewed patches have been landed. Closing bug.
This did not fix bug 197611, so something else is going on there.