Comment 4 for bug 1249971

Reviewed: https://review.openstack.org/64008
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=ed41b6804a8eafb710f8faec425e22ebe0b85ca9
Submitter: Jenkins
Branch: stable/havana

commit ed41b6804a8eafb710f8faec425e22ebe0b85ca9
Author: ling-yun <email address hidden>
Date: Mon Nov 11 22:00:03 2013 +0800

    Update quota-set throw 500 error

    The server doesn't check whether the parameter "quota_set" or
    "quota_class_set" is in request
    body.So the 500 error has been thrown.

    We should catch the KeyError and transfer the KeyError to
    400(HTTPBadRequest) instead of 500.

    Closes-Bug: #1249971
    (cherry picked from commit 2ed2f3aff8eee70e02eb995780af292057cfcad4)
    Change-Id: I01260c77efa50324f3d203888689cdb1e94d2c21