Don't keep an empty draft

[mzorz]

Expected behavior

if I start a draft and do nothing, get out of the editor, we should delete the post entirely

Actual behavior

if I start a draft and do nothing, get out of the editor, it gets saved, so I get an empty draft in the list.

Tested on [device], Android [version]

[mzorz]

Not applicable anymore - tested both on Visual and Aztec editors, on current prod version.