result of wsrep logic in queue_for_group_commit was being ignored

This could cause out of order wsrep checkpoints due wsrep specific leader
code not being executed in `MYSQL_BIN_LOG::write_transaction_to_binlog_events`.
Move original result assignment to before wsrep logic to prevent that.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

Author: Leandro Pacheco

sql/log.cc

@@ -7768,6 +7768,8 @@ MYSQL_BIN_LOG::queue_for_group_commit(group_commit_entry *orig_entry)
     cur= entry->thd->wait_for_commit_ptr;
   }
 
+  result= orig_queue == NULL;
+
 #ifdef WITH_WSREP
   if (wsrep_is_active(entry->thd) &&
       wsrep_run_commit_hook(entry->thd, entry->all))
@@ -7791,7 +7793,6 @@ MYSQL_BIN_LOG::queue_for_group_commit(group_commit_entry *orig_entry)
 
   DBUG_PRINT("info", ("Queued for group commit as %s",
                       (orig_queue == NULL) ? "leader" : "participant"));
-  result= orig_queue == NULL;
 
 end:
   if (backup_lock_released)