master 03dc54b: Fix precision scrolling down for multi-line display strings

[Po Lu]

branch: master
commit 03dc54ba7fbd83e93b6841acbed14ae8ce319b7c
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Fix precision scrolling down for multi-line display strings
    
    * lisp/pixel-scroll.el
    (pixel-scroll-precision-scroll-down-page): Make sure Y delta
    is appropriate before deciding on next-pos.
---
 lisp/pixel-scroll.el | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lisp/pixel-scroll.el b/lisp/pixel-scroll.el
index 223bc7f..975c513 100644
--- a/lisp/pixel-scroll.el
+++ b/lisp/pixel-scroll.el
@@ -461,6 +461,11 @@ the height of the current window."
                      (when (zerop (vertical-motion (1+ scroll-margin)))
                        (set-window-start nil desired-start)
                        (signal 'end-of-buffer nil))
+                     (while (when-let ((posn (posn-at-point)))
+                              (< (cdr (posn-x-y posn)) delta))
+                       (when (zerop (vertical-motion 1))
+                         (set-window-start nil desired-start)
+                         (signal 'end-of-buffer nil)))
                      (point)))
          (scroll-preserve-screen-position nil)
          (auto-window-vscroll nil))