Replace 2 checks in rmailsum.el with 'pos-visible-in-window-p'

* lisp/mail/rmailsum.el (rmail-summary-scroll-msg-up)
(rmail-summary-scroll-msg-down): Use 'pos-visible-in-window-p'
instead of checking the condition by hand.

1 files changed, 2 insertions, 9 deletions

diff --git a/lisp/mail/rmailsum.el b/lisp/mail/rmailsum.el
index e5363d2198c..10345b63ae2 100644
--- a/lisp/mail/rmailsum.el
+++ b/lisp/mail/rmailsum.el
@@ -1315,11 +1315,7 @@ advance to the next message."
                 (select-window rmail-buffer-window)
                 (prog1
                     ;; Is EOB visible in the buffer?
-                    (save-excursion
-                      (let ((ht (window-height)))
-                        (move-to-window-line (- ht 2))
-                        (end-of-line)
-                        (eobp)))
+                    (pos-visible-in-window-p (point-max))
                   (select-window rmail-summary-window)))
               (if (not rmail-summary-scroll-between-messages)
                   (error "End of buffer")
@@ -1342,10 +1338,7 @@ move to the previous message."
                 (select-window rmail-buffer-window)
                 (prog1
                     ;; Is BOB visible in the buffer?
-                    (save-excursion
-                      (move-to-window-line 0)
-                      (beginning-of-line)
-                      (bobp))
+                    (pos-visible-in-window-p (point-min))
                   (select-window rmail-summary-window)))
               (if (not rmail-summary-scroll-between-messages)
                   (error "Beginning of buffer")