neovim

Problem:  File info disappears immediately when 'cmdheight' has just
          decreased due to switching tabpage and 'shortmess' doesn't
          contain 'o' or 'O'.
Solution: Make sure msg_row isn't smaller than cmdline_row.

fixes: vim/vim#13560
closes: vim/vim#13561

https://github.com/vim/vim/commit/40ed6711bd385051021691980e8ce16375b4b510