References to im_class.__name__ are not compatible with python3

[Tom Cameron]

References to im_class.__name__ will need to be changed to __self__.__class__.__name__.

For example, in notifications.py references to callback.im_class.__name__ should be callback.__self__.__class__.__name__.

https://github.com/openstack/keystone/blob/4f0107e43491ec5ed829b83eae7be32fea5ba659/keystone/notifications.py#L137-L143

[Tom Cameron (drdabbles)]

This bug report was requested as part of comments from Boris Bobrov in https://review.openstack.org/#/c/147313

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/158777

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/158777
Committed: https://git.openstack.org/cgit/openstack/keystone/commit/?id=dbb98ef7dbf85c3e03caa54250283c05d9087732
Submitter: Jenkins
Branch: master

commit dbb98ef7dbf85c3e03caa54250283c05d9087732
Author: Matthieu Huin <email address hidden>
Date: Tue Feb 24 17:29:21 2015 +0100

    Get method's class name in a python3-compatible way

    This way of getting an instance method's class name does not rely on
    the im_class attribute and is compatible with any version of python
    after 2.7

    Co-Authored-By: David Stanek <email address hidden>
    Change-Id: I7fffa2ec3c5fd68b8d36324ded6f58f26a93d419
    Closes-Bug: 1418643