patch 8.1.1419: listener callbacks may be called recursively

Problem:    Listener callbacks may be called recursively.
Solution:   Set "updating_screen" while listener callbacks are invoked.

src/version.c

@@ -767,6 +767,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1419,
 /**/
     1418,
 /**/