Created attachment 922059 [details]
development.log

Description of problem:
Given a scalable app has multiplier and min_gears set, when scaling down the application, an exception is raised 'Unable to complete the requested operation due to: comparison of Fixnum with nil failed\nReference ID: 4c4136d21460b7355833a0c152b4c3e4'

Version-Release number of selected component (if applicable):
On devenv_5021

How reproducible:
Always

Steps to Reproduce:
1. Create a scalable application, set min gears to 2
rhc create-app php5s php-5.3 -s
rhc cartridge-scale -c php-5.3 -a php5s --min 2
2. Set multiplier on broker
oo-admin-ctl-app -l jhou@redhat.com -a php5s --cartridge haproxy-1.4 -c set-multiplier --multiplier 1
3. Set min gears to 1 so that app can be scaled down
rhc cartridge-scale -c php-5.3 -a php5s --min 1
4. Scale down the app via RESTAPI
curl -s -k -H 'Content-Type: Application/json' --user jhou@redhat.com:xxx https://ec2-54-81-3-234.compute-1.amazonaws.com/broker/rest/domains/jhou/applications/php5s/events -X POST -d '{"event":"scale-down"}' | json_reformat

Actual results:
After step 4:
{
    "api_version": 1.7,
    "data": null,
    "messages": [
        {
            "exit_code": 1,
            "field": null,
            "index": null,
            "severity": "error",
            "text": "Unable to complete the requested operation due to: comparison of Fixnum with nil failed\nReference ID: fd678bcd499e924ad65de65fe109a30e"
        }
    ],
    "status": "internal_server_error",
    "supported_api_versions": [
        1.0,
        1.1,
        1.2,
        1.3,
        1.4,
        1.5,
        1.6,
        1.7
    ],
    "type": null,
    "version": "1.7"
}


Expected results:
Should scale down successfully

Additional info:
development.log attached.