Raise 400 if credentials not provided (bug 1044032)
Raise 400 if credentials not provided (bug 1044032)

This request:

    POST /v2.0/tokens

    {
        "auth": {
            "RAX-KSKEY:apiKeyCredentials": {
                "apiKey": "pass",
                "tenantName": "admin",
                "username": "admin"
            }
        }
    }

Now results in:

    400 Bad Request

    {
        "error": {
            "code": 400,
            "message": "Expecting to find passwordCredentials or token in auth. The server could not comply with the request since it is eithermalformed or otherwise incorrect. The client is assumed to be in error.",
            "title": "Bad Request"
        }
    }

Change-Id: I5caf2b15b1bf60e0e31e8afcc7fc227744bd933a

jonnary/keystone,nuxeh/keystone,cbrucks/Federated_Keystone,dstanek/keystone,idjaw/keystone,mahak/keystone,citrix-openstack-build/keystone,rushiagr/keystone,vivekdhayaal/keystone,ajayaa/keystone,himanshu-setia/keystone,MaheshIBM/keystone,jumpstarter-io/keystone,mahak/keystone,rickerc/keystone_audit,cernops/keystone,reeshupatel/demo,promptworks/keystone,maestro-hybrid-cloud/keystone,jamielennox/keystone,rushiagr/keystone,kwss/keystone,klmitch/keystone,roopali8/keystone,ntt-sic/keystone,himanshu-setia/keystone,rajalokan/keystone,ging/keystone,ajayaa/keystone,promptworks/keystone,MaheshIBM/keystone,cbrucks/Federated_Keystone,reeshupatel/demo,ntt-sic/keystone,vivekdhayaal/keystone,derekchiang/keystone,citrix-openstack-build/keystone,mahak/keystone,cloudbau/keystone,maestro-hybrid-cloud/keystone,takeshineshiro/keystone,dims/keystone,openstack/keystone,dsiddharth/access-keys,ilay09/keystone,rickerc/keystone_audit,dstanek/keystone,blueboxgroup/keystone,jumpstarter-io/keystone,jumpstarter-io/keystone,openstack/keystone,JioCloud/keystone,dims/keystone,UTSA-ICS/keystone-kerberos,kwss/keystone,blueboxgroup/keystone,citrix-openstack-build/keystone,rajalokan/keystone,vivekdhayaal/keystone,JioCloud/keystone,kwss/keystone,idjaw/keystone,cloudbau/keystone,UTSA-ICS/keystone-kerberos,ilay09/keystone,rodrigods/keystone,openstack/keystone,nuxeh/keystone,dsiddharth/access-keys,rushiagr/keystone,cernops/keystone,reeshupatel/demo,townbull/keystone-dtrust,cloudbau/keystone,derekchiang/keystone,promptworks/keystone,dsiddharth/access-keys,klmitch/keystone,ntt-sic/keystone,ilay09/keystone,ging/keystone,rodrigods/keystone,jonnary/keystone,rickerc/keystone_audit,dstanek/keystone,derekchiang/keystone,townbull/keystone-dtrust,townbull/keystone-dtrust,roopali8/keystone,cbrucks/Federated_Keystone,nuxeh/keystone,jamielennox/keystone,rajalokan/keystone,takeshineshiro/keystone