Comment 5 for bug 1473042

Reviewed: https://review.openstack.org/246844
Committed: https://git.openstack.org/cgit/openstack/keystone/commit/?id=bce8575c2027fc9f9cd2c2a7ad0cfc286df83c58
Submitter: Jenkins
Branch: master

commit bce8575c2027fc9f9cd2c2a7ad0cfc286df83c58
Author: Andrey Pavlov <email address hidden>
Date: Wed Nov 18 13:08:08 2015 +0300

    Fix string conversion in s3 handler for python 2

    creds_ref['secret'] in s3/ec2 controller has type unicode.
    and result type of six.b('AWS4' + secret) is an unicode.
    but hmac.new decoder can't work with unicode strings - it
    needs 'str' type in python 2.
    So here simple change is needed - encode result string as 'utf-8'.
    Same conversion we have in signature v1 checking.

    Also two comments from previous review was fixed.

    Change-Id: I80d862956eace35753f00459d49150a62f07101a
    Related-Bug: #1473042