To reproduce: 0. Enable tiled drawing 1. Search for "w-4" on Google 2. Click the first result, which should be a link to a W-4 PDF When the PDF loads, a cross-fade happens between the Google search results page. This looks kind of nice, but I don't think it's intentional.
<rdar://problem/10910808>
Created attachment 131932 [details] Patch
Created attachment 131937 [details] Patch
Committed r110780: <http://trac.webkit.org/changeset/110780>