ref: eb5676d4be3915af8e23071a4130922d634cebb4
parent: 9b194f23b2a544fab666e40f4f574c8fceb7601f
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Wed Dec 12 14:33:08 EST 2018
upas/fs: handle errors from fetch for cachebody()/cacheheaders() for imap, when a fetch fails, error out of read and stat. also don't add failed to download messages into the lru.