Try to fix assertion failures at slave shutdown when running

rpl_ndb tests on sapsrv1.


sql/ha_ndbcluster_binlog.cc:
  Try to fix assertion failures at slave shutdown when running
  rpl_ndb tests. If the binlog thread is killed, which happens during
  shutdown, open_tables returns error without setting an error
  in THD. Therefore one can't access thd->main_da.message() if thd->killed.

sql/ha_ndbcluster_binlog.cc

@@ -2326,6 +2326,9 @@ static int open_ndb_binlog_index(THD *thd, TABLE_LIST *tables,
   thd->clear_error();
   if (open_tables(thd, &tables, &counter, MYSQL_LOCK_IGNORE_FLUSH))
   {
+    if (thd->killed)
+      sql_print_error("NDB Binlog: Opening ndb_binlog_index: killed");
+    else
       sql_print_error("NDB Binlog: Opening ndb_binlog_index: %d, '%s'",
                       thd->main_da.sql_errno(),
                       thd->main_da.message());