MDEV-9051 mysqld got signal 11, after upgrade to 10.1.8

feedback plugin needs to set tables->select_lex properly

mysql-test/suite/plugins/r/feedback_plugin_send.result

@@ -14,5 +14,6 @@ FEEDBACK_SEND_RETRY_WAIT	60
 FEEDBACK_SEND_TIMEOUT	60
 FEEDBACK_URL	http://mariadb.org/feedback_plugin/post
 FEEDBACK_USER_INFO	mysql-test
+set global sql_mode=ONLY_FULL_GROUP_BY;
 6: feedback plugin: report to 'http://mariadb.org/feedback_plugin/post' was sent
 6: feedback plugin: server replied 'ok'

mysql-test/suite/plugins/t/feedback_plugin_send.test

@@ -13,7 +13,11 @@ if (!$MTR_FEEDBACK_PLUGIN) {
 # Let's wait, and hope that mtr is started with --parallel and
 # is doing some work in other workers.
 #
-sleep 310;
+
+sleep 100;
+set global sql_mode=ONLY_FULL_GROUP_BY;
+sleep 210;
+
 
 # The test expects that the plugin will send a report at least 2 times,
 # now (5 min after loading) and on server shutdown which happens below. 

plugin/feedback/sender_thread.cc

@@ -124,6 +124,7 @@ static int prepare_for_fill(TABLE_LIST *tables)
   if (!tables->table)
     return 1;
 
+  tables->select_lex= thd->lex->current_select;
   tables->table->pos_in_table_list= tables;
 
   return 0;