Steps to reproduce:
1. register capture agent with URL
2. update agent's state, and pass url field just like in /docs.html?path=/capture-admin
3. agent's URL is not saved into database / not displayed on Capture Admin tab
Workaround (if any):
Committed to trunk in rev 12272. Merged to 1.3.x in rev 12273. Merged to 1.4.x in rev 12274.