Canvas2DLayerChromium::updateCompositorResources should issue a glFlush after copying the canvas back buffer texture to the front buffer. Otherwise the canvas may start rendering new context before the copy is performed, causing the copy to source from partially rendered data.
The flush was there previously but got mistakenly removed when the new TextureCopier utility was added.
Created attachment 135313 [details]
Comment on attachment 135313 [details]
Clearing flags on attachment: 135313
Committed r113033: <http://trac.webkit.org/changeset/113033>
All reviewed patches have been landed. Closing bug.