signon_identity_signout does not delete credentials from gnome keyring

Hey,

In clean installation of raring, signon_identity_signout function does not work, and while it returns with success the login credentials are still kept in gnome-keyring.

Example python script to reproduce this issue:

#!/usr/bin/env python3

import argparse
import sys

from gi.repository import GLib
from gi.repository import GObject
from gi.repository import Accounts
from gi.repository import Signon

class AccountConsole:
    def __init__(self):
        self.manager = Accounts.Manager()

    def list_accounts(self, args):
        accounts = self.manager.list()
        if not accounts:
            print('No accounts')
            main_loop.quit()
            return

        for account_id in accounts:
            account = self.manager.get_account(account_id)
            enabledness = 'enabled' if account.get_enabled() else 'disabled'
            print('account: id %s, %s, provider: %s' % (account_id, enabledness, account.get_provider_name()))
        main_loop.quit()

    def remove_credentials(self, args):
        self.args = args
        self.account = account = self.manager.get_account(args.account)
        if self.account is None:
            print("no such account")
            main_loop.quit()
            return
        value, signon_id = account.get_variant(args.signon_id_field )
        if value is not None and signon_id != Accounts.SettingSource.NONE:
           self.account.set_enabled(False)
            # is still stored even though the user would believe they have been deleted
            print ( signon_id )
            self.identity = Signon.Identity.new_from_db( signon_id )
            if self.identity is not None:
                self.identity.signout(lambda x,y,z:
                        self.account.store(lambda x,y,z:
                            [print("done"),main_loop.quit() ], 0)
                    , 0 )
        else:
            print ("No credentials set for account")
            main_loop.quit()

    def on_credentials_stored(self, identity, id, error, account):
        self.account.set_variant(self.args.signon_id_field, GLib.Variant('u', id))
        self.account.store(lambda x,y,z: [print("done"), main_loop.quit() ], None)

app = AccountConsole()

parser = argparse.ArgumentParser(description='Command-line tool for account handling')
subparsers = parser.add_subparsers(title='Valid actions')

subparser = subparsers.add_parser('list',
        help='List existing accounts')
subparser.set_defaults(func=app.list_accounts)

subparser = subparsers.add_parser('remove_credentials',
        help='Remove credentials for an account')
subparser.add_argument('account', type=int,
        help='Id of the SignOn identity')
subparser.add_argument('--signon-id-field', type=str, default='CredentialsId',
        help='Name of the key holding the SignOn ID')
subparser.set_defaults(func=app.remove_credentials)

args = parser.parse_args()
if 'func' in args:
    main_loop = GLib.MainLoop()
    GLib.idle_add(args.func, args)
    main_loop.run()
else:
    parser.print_help()

steps:
1) Launch "credentials-preferences" and create a new account
2) check the password in gnome-keyring
3) execute the above script with "list" parameter
4) execute the above script with "remove_credentials <account_number>"
5) check the password in gnome-keyring (fail: the password have not been deleted). Expected result: credentials have been deleted

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: signond 8.49-0ubuntu2
ProcVersionSignature: Ubuntu 3.8.0-19.29-generic 3.8.8
Uname: Linux 3.8.0-19-generic i686
ApportVersion: 2.9.2-0ubuntu8
Architecture: i386
Date: Thu Apr 25 14:04:27 2013
InstallationDate: Installed on 2013-04-24 (0 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release i386 (20130424)
MarkForUpload: True
SourcePackage: signon
UpgradeStatus: No upgrade log present (probably fresh install)