bug#68958: [PATCH] Support bookmarking Xref results buffers

[Juri Linkov]

>> Is that for use with desktop-mode only?
>
> What do you mean?  To be clear, this is unrelated to desktop-mode, or at
> least I didn't design/implement any of this with desktop-mode in mind.

Desktop-mode is from the parallel discussion that I started to consider
other beneficial outcomes of applying your patch.  It will also allow
to replace xref-revert-buffer with revert-buffer-function: currently
xref-revert-buffer uses xref--fetcher, but with revert-buffer-function
could use xref-fetcher-alist.