patch 8.2.4739: accessing freed memory after WinScrolled autocmd event

Problem:    Accessing freed memory after WinScrolled autocmd event.
Solution:   Check the window pointer is still valid. (closes #10156)
            Remove the argument from may_trigger_winscrolled().
diff --git a/src/version.c b/src/version.c
index 27de4e5..84c669b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -747,6 +747,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4739,
+/**/
     4738,
 /**/
     4737,