master 7f6dba0 1/3: Unbreak xref-goto-xref in Emacs 26

[Dmitry Gutov]

branch: master
commit 7f6dba00edcccd6510185108a5c4bbb010393230
Author: Dmitry Gutov <dgutov@yandex.ru>
Commit: Dmitry Gutov <dgutov@yandex.ru>

    Unbreak xref-goto-xref in Emacs 26
    
    * lisp/progmodes/xref.el (xref-goto-xref):
    Call next-error-found only if it's defined (bug#42981).
---
 lisp/progmodes/xref.el | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lisp/progmodes/xref.el b/lisp/progmodes/xref.el
index bbf899e..4da7b4e 100644
--- a/lisp/progmodes/xref.el
+++ b/lisp/progmodes/xref.el
@@ -608,7 +608,10 @@ buffer."
                    (user-error "No reference at point")))
          (xref--current-item xref))
     (xref--show-location (xref-item-location xref) (if quit 'quit t))
-    (next-error-found buffer (current-buffer))))
+    (if (fboundp 'next-error-found)
+        (next-error-found buffer (current-buffer))
+      ;; Emacs < 27
+      (setq next-error-last-buffer buffer))))
 
 (defun xref-quit-and-goto-xref ()
   "Quit *xref* buffer, then jump to xref on current line."