Glance API returns a 500 response code for invalid request params

[Unmesh Gurjar]

When the Glance API for replace image members is provided with an invalid request body, it returns an Internal Server Error(500).
The API should return a Bad Request(400) response instead.

Here is the sample Json request body:
{"test": [ {"member_id": "demo", "can_share": false}]}

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/3228

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/3228
Committed: http://github.com/openstack/glance/commit/eb2ab3a40a7ddc6038a254c27870f92cfd012d24
Submitter: Jenkins
Branch: master

commit eb2ab3a40a7ddc6038a254c27870f92cfd012d24
Author: Kevin L. Mitchell <email address hidden>
Date: Fri Jan 20 13:31:47 2012 -0600

    Return 400 if registry returns 400.

    Fixes bug 919244. The registry would return 400 for invalid input,
    which resulted in an exception.Invalid being thrown in the registry
    client. There was no exception handler for this exception, so it
    got bubbled up and turned into a 500. This should fix the problem
    by adding the missing exception handlers.

    Change-Id: I75ecfec1c0b0b4b3df1a8c9ace83e75d19527c93