bug#28407: 26.0.50; xref should use imenu

[Eli Zaretskii]

> Cc: Tom Tromey <tom@tromey.com>, 28407@debbugs.gnu.org
> From: Visuwesh <visuweshm@gmail.com>
> Date: Sat, 25 Jun 2022 19:34:48 +0530
> 
> [ To elaborate, say that I visited the TAGS residing in Emacs' src/
>   directory then switched to another project.  Now, if I do C-u
>   M-. Fplist_get RET, then it will take me to the Emacs project!!  This
>   seems to be a general problem with the etags backend tho.  ]

In general, when you visit a new TAGS file, etags asks you whether to
replace the previous one or to keep them both.  Maybe the way you
"switch to another project" somehow hides that prompt/decision?