MWL#90: subquery optimizations

- Remove redundant changes againist 5.3-main

sql/sql_base.cc

@@ -7788,6 +7788,7 @@ bool setup_tables(THD *thd, Name_resolution_context *context,
       }
       DBUG_ASSERT(item == table_list->jtbm_subselect);
       table_list->jtbm_subselect->setup_engine(FALSE);
+      //psergey-merge: ^ todo: error checking!
     }
   }