Bug#14157: utf8 encoding in binlog without set character_set_client

adapting to pushbuild's custom to switch from default pathes. The name for
var directory must be set with MYSQLTEST_VARDIR.

mysql-test/t/mysqlbinlog.test

@@ -131,7 +131,7 @@ flush logs;
 # resulted binlog, parly consisting of multi-byte utf8 chars, 
 # must be digestable for both client and server. In 4.1 the client 
 # should use default-character-set same as the server.
---exec $MYSQL_BINLOG --short-form $MYSQL_TEST_DIR/var/log/master-bin.000006 | $MYSQL
+--exec $MYSQL_BINLOG --short-form $MYSQLTEST_VARDIR/log/master-bin.000006 | $MYSQL
 select * from t5  /* must be (1),(1) */;
 
 # clean up