We need to ensure that layout is up-to-date when hit testing, but there are many code paths that don't do this currently. We should add ASSERT(!needsLayout()) to RenderView::needsLayout() and fix all the callers. Also need to remove the renderer().document().updateLayout(); in RenderLayer:hitTest().
Done by the patch in bug 136651. *** This bug has been marked as a duplicate of bug 136651 ***