Bug 104746 – REGRESSION (r137006): TileCache flashes to linen, rather than the background color, when scrolling fast

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Simon Fraser (smfr)]

After r137006, tile cache flashes now flash to linen rather than the background color, making them look much worse.

[Radar WebKit Bug Importer]

<rdar://problem/12860678>

[Noam Rosenthal]

How does one reproduce this?

[Simon Fraser (smfr)]

Scroll really fast (or hit Home/End) on a long page, like http://www.w3.org/2012/08/13-css-irc

[Simon Fraser (smfr)]

Created attachment 178942 [details]
Patch, but test updates needed

[Simon Fraser (smfr)]

Comment on attachment 178942 [details]
Patch, but test updates needed

I think this patch is correct, but it affects all the layout test results, and I wonder if we should set the root layer's background color on all platforms.

[WebKit Review Bot]

Comment on attachment 178942 [details]
Patch, but test updates needed

Attachment 178942 [details] did not pass chromium-ews (chromium-xvfb):
Output: http://queues.webkit.org/results/15277406

New failing tests:
compositing/geometry/bounds-clipped-composited-child.html
compositing/geometry/clip.html
compositing/geometry/limit-layer-bounds-positioned.html
compositing/geometry/bounds-ignores-hidden-composited-descendant.html
compositing/geometry/bounds-ignores-hidden.html
compositing/geometry/limit-layer-bounds-clipping-ancestor.html
compositing/backing/no-backing-for-clip-overlap.html
compositing/bounds-in-flipped-writing-mode.html
compositing/geometry/fixed-position-composited-switch.html
compositing/geometry/limit-layer-bounds-transformed-overflow.html
compositing/iframes/become-overlapped-iframe.html
compositing/geometry/foreground-layer.html
compositing/absolute-inside-out-of-view-fixed.html
compositing/geometry/limit-layer-bounds-overflow-root.html
compositing/geometry/limit-layer-bounds-fixed-positioned.html
compositing/geometry/layer-due-to-layer-children-deep-switch.html
compositing/geometry/ancestor-overflow-change.html
compositing/geometry/limit-layer-bounds-positioned-transition.html
compositing/geometry/clip-inside.html
compositing/geometry/layer-due-to-layer-children-switch.html
compositing/geometry/bounds-ignores-hidden-dynamic-negzindex.html
compositing/columns/composited-in-paginated.html
compositing/iframes/become-composited-nested-iframes.html
compositing/geometry/bounds-ignores-hidden-dynamic.html
compositing/geometry/limit-layer-bounds-transformed.html
compositing/clip-child-by-non-stacking-ancestor.html
compositing/geometry/flipped-writing-mode.html
compositing/overflow-trumps-transform-style.html
compositing/backing/no-backing-for-clip.html
compositing/backing/no-backing-for-perspective.html

[Simon Fraser (smfr)]

Created attachment 178963 [details]
Patch

[Darin Adler]

Comment on attachment 178963 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=178963&action=review

> Source/WebCore/ChangeLog:19
> +        (WebCore::clipBox): Remove blank linke.

Typo "linke".

[Simon Fraser (smfr)]

Comment on attachment 178963 [details]
Patch

This broke a couple of the new background tests.

[Noam Rosenthal]

(In reply to comment #9)
> (From update of attachment 178963 [details])
> This broke a couple of the new background tests.

> compositing/background-color/background-color-text-change.html failed unexpectedly (reference mismatch)

At least this one seems like a legitimate failure, probably from the change to updateBackgroundColor.
Let me know if you want me to take a look.

[Simon Fraser (smfr)]

http://trac.webkit.org/changeset/137800