BUG#46166

Post merge fix. In write_incident, check if binlog file is
opened before actually trying to write the incident event.

sql/log.cc

@@ -4828,6 +4828,10 @@ bool MYSQL_BIN_LOG::write_incident(THD *thd, bool lock)
 {
   uint error= 0;
   DBUG_ENTER("MYSQL_BIN_LOG::write_incident");
+
+  if (!is_open())
+    DBUG_RETURN(error);
+
   LEX_STRING const write_error_msg=
     { C_STRING_WITH_LEN("error writing to the binary log") };
   Incident incident= INCIDENT_LOST_EVENTS;