bug#22947: 25.0.92; xref-find-definitions fails for Perl & etags

[Bob Rogers]

   From: Eli Zaretskii <eliz@gnu.org>
   Date: Thu, 10 Mar 2016 22:32:24 +0200

   > Sure; I will do so when I get home this evening.  (If you could give me
   > a quick recipe for fetching the right branch, it might speed things up;
   > I'm still a Git beginner.)

     git clone git://git.savannah.gnu.org/emacs.git

   followed by

     git checkout emacs-25

Thank you; I wound up rebuilding the whole thing with revision 8b8a6ad.
The new etags builds the table without package qualifications, but after
"emacs -Q" and "M-x visit-tags-table", "M-." still doesn't find either
the parse_recipes or add_ingredient definitions.  FWIW, the previous
version of emacs was able to find both add_ingredient definitions, but
not parse_recipes.

   >    Also, FWIW, I thought I should mention that M-x find-tag works
   > correctly with the existing etags output . . .

   Yes, but we are switching away of find-tag towards the xref commands.

The user interface, yes, but it seemed worthy of note that the find-tag
backend works with the original etags output . . .

                                        -- Bob