From the buildbot output:
ASSERTION FAILED: loader->handle()
(/Users/buildbot/Desktop/BuildData/WebKit-BuildSlave/post-commit-leaks-powerpc-mac-os-x/build/WebCore/loader/loader.cpp:142 virtual void WebCore::Loader::didReceiveResponse(WebCore::SubresourceLoader*, const WebCore::ResourceResponse&))
I am seeing this locally with 100% reproducibility on editing/pasteboard/paste-RTFD.html and editing/pasteboard/paste-TIFF.html. This has been broken since the tests were landed in r19244 as part of the fix for bug 10725.
I have disabled the two tests that are causing the assertion failure so that the layout tests run to completion. Having the layout tests busted for over 10 hours makes me nervous.
Fixed in r19267 by Anders.