MDEV-9544 FLUSH [RELAY] LOGS does not rotate logs for a named slave9544

Problem:- In the case of multisource replication/named slave
when we run "FLUSH LOGS" , it does not flush logs.

Solution:- A new function Master_info_index->flush_all_relay_logs()
is created which will rotate relay logs for all named slave.
This will be called in reload_acl_and_cache function when
connection_name.length == 0

1 files changed, 112 insertions, 0 deletions

diff --git a/mysql-test/suite/multi_source/mdev-9544.test b/mysql-test/suite/multi_source/mdev-9544.test
new file mode 100644
index 00000000000..025a86d660b
--- /dev/null
+++ b/mysql-test/suite/multi_source/mdev-9544.test
@@ -0,0 +1,112 @@
+--source include/not_embedded.inc
+--source include/have_innodb.inc
+--source include/have_debug.inc
+
+--connect (server_1,127.0.0.1,root,,,$SERVER_MYPORT_1)
+--connect (server_2,127.0.0.1,root,,,$SERVER_MYPORT_2)
+--connect (server_3,127.0.0.1,root,,,$SERVER_MYPORT_3)
+--connect (server_4,127.0.0.1,root,,,$SERVER_MYPORT_4)
+
+--connection server_1
+create database a;
+use a;
+create table t1(a int);
+insert into t1 values(1);
+create table t2(a int);
+insert into t2 values(1);
+--save_master_pos
+
+--connection server_2
+create database b;
+use b;
+create table t1(a int);
+insert into t1 values(1);
+create table t2(a int);
+insert into t2 values(1);
+--save_master_pos
+
+--connection server_3
+create database c;
+use c;
+create table t1(a int);
+insert into t1 values(1);
+create table t2(a int);
+insert into t2 values(1);
+--save_master_pos
+
+--connection server_4
+--disable_warnings
+--replace_result $SERVER_MYPORT_1 MYPORT_1
+eval change master 'm1' to master_port=$SERVER_MYPORT_1 , master_host='127.0.0.1', master_user='root';
+--replace_result $SERVER_MYPORT_2 MYPORT_2
+eval change master 'm2' to master_port=$SERVER_MYPORT_2 , master_host='127.0.0.1', master_user='root';
+--replace_result $SERVER_MYPORT_3 MYPORT_3
+eval change master  to master_port=$SERVER_MYPORT_3 , master_host='127.0.0.1', master_user='root';
+start all slaves;
+set default_master_connection = 'm1';
+--source include/wait_for_slave_to_start.inc
+set default_master_connection = 'm2';
+--source include/wait_for_slave_to_start.inc
+set default_master_connection = '';
+--source include/wait_for_slave_to_start.inc
+
+--enable_warnings
+--sync_with_master 0,'m1'
+--sync_with_master 0,'m2'
+--sync_with_master 0,''
+use a;
+show tables;
+use b;
+show tables;
+use c;
+show tables;
+--echo #TEST
+SET default_master_connection = "m1";
+--let $old_m1 = query_get_value("show relaylog events;", "Log_name",1)
+SET default_master_connection = "m2";
+--let $old_m2 = query_get_value("show relaylog events;", "Log_name",1)
+SET default_master_connection = "";
+--let $old__ = query_get_value("show relaylog events;", "Log_name",1)
+flush logs;
+--sleep 2
+SET default_master_connection = "m1";
+--let $new_m1 = query_get_value("show relaylog events;", "Log_name",1)
+--if ($new_m1 != $old_m1) {
+	--echo #log Rotated
+}
+SET default_master_connection = "m2";
+--let $new_m2 = query_get_value("show relaylog events;", "Log_name",1)
+--if ($new_m2 != $old_m2) {
+	--echo #log Rotated
+}
+SET default_master_connection = "";
+--let $new__ = query_get_value("show relaylog events;", "Log_name",1)
+--if ($new__ != $old__) {
+	--echo #log Rotated
+}
+
+--echo #CleanUp
+--connection server_1
+drop database a;
+--save_master_pos
+
+--connection server_2
+drop database b;
+--save_master_pos
+
+--connection server_3
+drop database c;
+--save_master_pos
+
+--connection server_4
+--sync_with_master 0,'m1'
+--sync_with_master 0,'m2'
+--sync_with_master 0,''
+stop all slaves;
+SET default_master_connection = "m1";
+--source include/wait_for_slave_to_stop.inc
+SET default_master_connection = "m2";
+--source include/wait_for_slave_to_stop.inc
+SET default_master_connection = "";
+--source include/wait_for_slave_to_stop.inc
+