Mail w/ only inline image not display: Closes #7563
Mail w/ only inline image not display: Closes #7563

Problem with internal processing of message not recognizing that
the ImageReplacer's HTML qualifies as "processed" HTML.

emersion/geary,glebihan/geary,aatishnn/geary,geekvigilante/geary,tshikaboom/geary,tshikaboom/geary,aatishnn/geary,martinra/geary,rschroll/geary,AtticHacker/geary,tshikaboom/geary,AtticHacker/geary,jimbonator/geary,githubnemo/geary,robol/geary,rschroll/geary,emersion/geary,aatishnn/geary,githubnemo/geary,githubnemo/geary,mjog/geary,glebihan/geary,MohamedIM/geary-unofficial,robol/geary,abn/geary,emersion/geary,robol/geary,martinra/geary,AtticHacker/geary,glebihan/geary,jimbonator/geary,kpiwko/geary,mpdeimos/geary,mjog/geary,martinra/geary,mjog/geary,jimbonator/geary