Comment 5 for bug 1657459

So the fundamental part of this is that there's a subtle change in webob 1.7.0 in how webob.request.Request.is_body_readable is implemented.

On 1.7.0, it tells Glance that the body is not readable so it prevents it from reaching certain checks that would produce the appropriate responses. This commit is the root cause of several of Glance's test failures: https://github.com/Pylons/webob/commit/0e6fcbfbc58af6fdd4e125543bf8f5fb91b984c6