bug#28407: 26.0.50; xref should use imenu

[Eli Zaretskii]

> From: Visuwesh <visuweshm@gmail.com>
> Cc: tom@tromey.com,  28407@debbugs.gnu.org,  dgutov@yandex.ru
> Date: Sat, 25 Jun 2022 20:07:25 +0530
> 
> [சனி ஜூன் 25, 2022] Eli Zaretskii wrote:
> 
> > 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?
> 
> It does ask me to replace the previous one but I expected Emacs to
> restrict the TAGS file to the buffer I selected it from

That'd be against the purpose of TAGS tables: their explicit purpose
is to allow you to find definitions in _other_ files.  And Emacs
cannot know whether the fact that you loaded another TAGS table means
that you want to "forget" about the previous one, as long as you keep
it loaded.