An additional "Blocked access to external URL" message is frequently added to the top of the output in Debug bots, which causes the test to fail. I'm marking it flaky for now.
Created attachment 182664 [details] Patch
This test was flaky earlier. I had hoped that http://trac.webkit.org/changeset/139502 would alleviate the flakiness, but my hopes are now dashed on the rocks. This patch reverts back to the non-flaky version of the test (which omits checking for image loads).
Comment on attachment 182664 [details] Patch TY!
Comment on attachment 182664 [details] Patch Clearing flags on attachment: 182664 Committed r139703: <http://trac.webkit.org/changeset/139703>
All reviewed patches have been landed. Closing bug.