bug#35702: xref revert-buffer

[Eli Zaretskii]

> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Fri, 24 May 2019 04:51:51 +0300
> 
> Version: 27.1
> 
> On 12.05.2019 22:45, Juri Linkov wrote:
> > I tried to use project-find-regexp more often than rgrep,
> > but xref misses an important feature: typing 'g' in the
> > *xref* buffer
> 
> Should work now, please see the commit 62349fe82a.

Thanks, but that changeset has a few problems:

  . the new command xref--revert-xref-buffer uses an internal name,
    and has no doc string
  . neither NEWS nor the user manual document the 'g' key in XREF
    buffers
  . it looks like this new command is not useful after M-., because I
    get an error message when I try using it (perhaps this is because
    I didn't understand its use case due to lack of docs)

Let me know if I can help in fixing any of the above.  (I tried to
figure out what this command does and how, but quickly got lost in a
chain of indirections via undocumented internal functions and
variables, sorry.)