patch 8.2.3394: filler lines are wrong when changing text in diff mode

Problem:    Filler lines are wrong when changing text in diff mode.
Solution:   Don't change the filler lines on every change.  Check
            scrollbinding when updating the filler lines. (closes #8809)

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3394,
 /**/
     3393,
 /**/