Create a new team UI has optional renewal period, then returns an error when not supplied

[Brian Fromme]

I selected "Create a new team" (https://launchpad.net/people/+newteam). I see that the "Renewal period" is labeled "(Optional)" So, I left this field blank, but I set Renewal Policy to Ondemand or Automatic,

After I submit the page, I get this error:

You must specify a default renewal period greater than 0.

The UI does not reflect the rules. Renewal Period is optional because the value is ignored when the Renewal Policy is None (the default value) The UI must not suggest the user provide the value if it will not be used. When the Renewal Policy is Ondemand or Automatic, the UI must ask the user to provide a Renewal Period.

Since users can be confused when choosing a sensible Renewal Period, the field could contain 365 by default. So regardless of what policy the user chooses, the period has a value that will be accepted.

[Curtis Hovey (sinzui)]

Updating the field to have a sensible period is trivial. Toggling the period field to disabled when the policy is None requires Javascript. The Enable Bug Expiration field has similar rules and maybe the JS can be extended or used as a template. The Period field should be indented under the policy field to show that it is subordinate (as is done with the Enable Bug Expiration field).