Description of problem:
Create a hostgroup with a KS repository and save. Go to edit it and notice the ks group is not displayed (even though it is in the database)

Version-Release number of selected component (if applicable):
6.15,6.14 (might be in 6.13 also...)

How reproducible: always

Steps to Reproduce:
1. Sync a kickstart repository ks-zoo (I synced => https://partha.fedorapeople.org/test-repos/kickstart-zoo/)
2. Create a hostgroup with Library/Default Org View/x86_64/Redhat-7/ks-zoo in synced content.
3. Save the hostgroup
4. Click on the hostgroup again and go to Operating System tab

Actual results:
Notice that Synced Content is not populated

Expected results:
Synced Content should be showing ks-zoo

Additional info:

If you looked at the content facet of the host group in rails console you clearly see that the KS repo is actually set. Its just not populated in the dropdown