Fake test logger didn't appointed to an instance attribute.

[Ilya Pekelny]

Fake logger didn't appointed to an instance attribute https://github.com/openstack/oslo.test/blob/master/oslotest/base.py#L64 .

From FakeLogger docstring follows:

     test_log(self)
          fixture = self.useFixture(LoggerFixture())
          logging.info('message')
          self.assertEqual('message', fixture.output)

A fake logger instance has a property `output` which must be accessible from BaseTestCase subclasses instances.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/78993
Committed: https://git.openstack.org/cgit/openstack/oslo.test/commit/?id=7d06dac0c0fba493c62274557215ac339a1e9093
Submitter: Jenkins
Branch: master

commit 7d06dac0c0fba493c62274557215ac339a1e9093
Author: Ilya Pekelny <email address hidden>
Date: Fri Mar 7 17:34:34 2014 +0200

    Fake logger as instance attribute

    Fake logger returned by fixtures.FakeLogger must be BaseTestCase instance
    attribute. Suchwise fake logger is accesible in BaseTestCase subclasses.

    Closes-Bug: #1289403
    Change-Id: I44afc23483f3bf0f031ba15d7f88e83b8be6f413