Problem:
A successful `BufReadCmd` can leave an existing `filetype` without
rerunning its `FileType` setup, so state cleared during reload may not
be restored.
This also causes `:edit`/reload syntax `directoryDirectory` groups to
not be reapplied.
Solution:
After `BufReadCmd` handles a read, trigger `FileType` for the existing
`filetype` if no `FileType` event fired during the read.