ssia.
Created attachment 243218 [details] Test reduction. 1. Turn on ‘show compositing layer’ setting in Safari. 2. Open attached test case. Observe that the before content does not get composited. (lack of compositing border) 
rdar://problem/19237334
Created attachment 243226 [details] Patch
Created attachment 243227 [details] Patch
Comment on attachment 243227 [details] Patch Attachment 243227 [details] did not pass mac-ews (mac): Output: http://webkit-queues.appspot.com/results/5649633896300544 New failing tests: compositing/fixed-positioned-pseudo-content-no-compositing.html
Created attachment 243232 [details] Archive of layout-test-results from ews100 for mac-mountainlion The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews100 Port: mac-mountainlion Platform: Mac OS X 10.8.5
Created attachment 243261 [details] Patch
Comment on attachment 243261 [details] Patch Attachment 243261 [details] did not pass mac-ews (mac): Output: http://webkit-queues.appspot.com/results/6165668579770368 New failing tests: compositing/fixed-positioned-pseudo-content-no-compositing.html
Created attachment 243263 [details] Archive of layout-test-results from ews102 for mac-mountainlion The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews102 Port: mac-mountainlion Platform: Mac OS X 10.8.5
Created attachment 243264 [details] Patch
Comment on attachment 243264 [details] Patch Clearing flags on attachment: 243264 Committed r177258: <http://trac.webkit.org/changeset/177258>
All reviewed patches have been landed. Closing bug.