The attached testcase shows that repainting with a layoutDelta in effect is broken when an ancestor is transformed.
Created attachment 26585 [details] Testcase
Actually I think the testcase is showing an issue with LayoutState, not layoutDelta.
Created attachment 26595 [details] Patch, LayoutTest changelog I changed RenderBlock::layoutOnlyPositionedObjects() to use the same criteria as RenderBlock::layoutBlock() for disabling layoutState, because testing showed that layoutOnlyPositionedObjects() could be hit for a block with a reflection. I think this is the right thing to do.
Committing to http://svn.webkit.org/repository/webkit/trunk ... M LayoutTests/ChangeLog A LayoutTests/fast/repaint/transform-disable-layoutstate.html A LayoutTests/platform/mac/fast/repaint/transform-disable-layoutstate-expected.checksum A LayoutTests/platform/mac/fast/repaint/transform-disable-layoutstate-expected.png A LayoutTests/platform/mac/fast/repaint/transform-disable-layoutstate-expected.txt M WebCore/ChangeLog M WebCore/rendering/RenderBlock.cpp M WebCore/rendering/RenderFlexibleBox.cpp Committed r39781
See also bug 23233.