Annotate_rows_log_event written for each wsrep streaming fragment

Annotate_rows_log_event is written for each wsrep streaming fragment.

To reproduce, start servers with the following options:

wsrep-trx-fragment-size=1

wsrep-trx-fragment-unit=ROWS

log-bin

log-slave-updates

log-bin-index=binlog-index

Run the following statements:

CREATE TABLE t1 (f1 INT PRIMARY KEY);

INSERT INTO t1 VALUES (1),(2);

Now binlog contains INSERT statement twice:

$ .mysqlbinlog mysqld-bin.000003 | grep '#Q> INSERT INTO'

#Q> INSERT INTO t1 VALUES (1),(2)

#Q> INSERT INTO t1 VALUES (1),(2)

This behavior will effectively make replication traffic scale as N^2 with small fragment sizes and bulk inserts with N rows.