patch 8.2.4915: sometimes the cursor is in the wrong position

Problem:    Sometimes the cursor is in the wrong position.
Solution:   When the cursor moved to another line, recompute w_botline.
            (closes #9736)
diff --git a/src/move.c b/src/move.c
index 31dc95b..5e31e71 100644
--- a/src/move.c
+++ b/src/move.c
@@ -489,7 +489,8 @@
     if (wp->w_cursor.lnum != wp->w_valid_cursor.lnum)
     {
 	wp->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL
-				     |VALID_CHEIGHT|VALID_CROW|VALID_TOPLINE);
+				      |VALID_CHEIGHT|VALID_CROW|VALID_TOPLINE
+				      |VALID_BOTLINE|VALID_BOTLINE_AP);
 	wp->w_valid_cursor = wp->w_cursor;
 	wp->w_valid_leftcol = wp->w_leftcol;
     }