bug#30320: 26.0.91; Crash when using lsp-ui-doc-mode

[Eli Zaretskii]

> Date: Sat, 10 Feb 2018 11:45:08 +0100
> From: martin rudalics <rudalics@gmx.at>
> CC: jake.goulding@gmail.com, 30320@debbugs.gnu.org
> 
>  > Does the below look reasonable and safe for emacs-26?
> 
> It does (the comments should be fixed) unless we want to guarantee a
> minimum width as well.

I considered the case of width, but couldn't find a case where 1 is
too few.  Is there some configuration where one or more columns are
taken by some display element other than text?  Also, cm.c only aborts
if the Y coordinate is wrong, it doesn't care about the X coordinate.