Test rpl.rpl_percona_userstat fails with --repeat=2

[Laurynas Biveinis]

On 5.6 trunk, with --repeat=2:

rpl.rpl_percona_userstat 'mix' w3 [ pass ] 330
rpl.rpl_percona_userstat 'mix' w3 [ fail ]
        Test ended at 2017-02-11 11:37:00

CURRENT_TEST: rpl.rpl_percona_userstat
mysqltest: In included file "./include/assert.inc":
included from ./include/assert.inc at line 75:
At line 74: Test assertion failed in assert.inc

The result from queries just before the failure was:
include/master-slave.inc
Warnings:
Note #### Sending passwords in plain text without SSL/TLS is extremely insecure.
Note #### Storing MySQL user name or password information in the master info repository is not secure and is therefore not recommended. Please consider using the USER and PASSWORD connection options for START SLAVE; see the 'START SLAVE Syntax' in the MySQL Manual for more information.
[connection master]
#
# Bug 995624 RBR events are not reflected in userstat's
# Rows_updated
#
SET @slave_userstat_saved= @@global.userstat;
SET GLOBAL userstat=ON;
include/assert.inc [Rows updated on slave should be equal to 0]
SET @master_userstat_saved= @@global.userstat;
SET GLOBAL userstat=ON;
include/assert.inc [Rows updated on master should be equal to 0]
######## Test assertion failed: Rows updated on master should be equal to 0 ########

The testcase probably needs FLUSH CLIENT_STATISTICS at the start and end

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PS-2237