BUG #11517: the pg_stat_replication.sync_stat show sync when synchronous_commit is set to be off

The following bug has been logged on the website:

Bug reference:      11517
Logged by:          the pg_stat_replication.sync_stat show sync when synchronous_commit is set
to be off
Email address:      amutu@amutu.com
PostgreSQL version: 9.2.4
Operating system:   suse linux 10 x86_64
Description:

from the doc,when synchronous_commit set to off or local,the commit will not
wait the remote slave reveive data,so it is not asynchronous replication.but
I find the pg_stat_replication wrongly report the sync_stat to sync.This can
be confused for people.

postgres=# select * from pg_stat_replication ;
-[ RECORD 1 ]----+------------------------------
pid              | 3213
usesysid         | 16387
usename          | rep
application_name | sync_slave
client_addr      | 172.25.38.154
client_hostname  |
client_port      | 54333
backend_start    | 2014-09-29 15:17:19.927457+08
state            | streaming
sent_location    | 21/A0F01C0
write_location   | 21/A0F01C0
flush_location   | 21/A0F01C0
replay_location  | 21/A0EFC88
sync_priority    | 1
sync_state       | sync

postgres=# show synchronous_standby_names ;
-[ RECORD 1 ]-------------+-----------------------
synchronous_standby_names | sync_slave,walreceiver


postgres=# show synchronous_commit ;
-[ RECORD 1 ]------+----
synchronous_commit | off