In NetworkJob::handleNotifyMultipartHeaderReceived function: when m_multipartResponse is null, we just created new one but not called setHTTPHeaderField. so we missed this received multipart Header.
Created attachment 157130 [details] Patch
Comment on attachment 157130 [details] Patch Looks good to me.
Comment on attachment 157130 [details] Patch Clearing flags on attachment: 157130 Committed r125022: <http://trac.webkit.org/changeset/125022>
All reviewed patches have been landed. Closing bug.