On the WebAdmin Permissions panel, invalid permissions should be styled differently

[Ryan J Ollos <ryano@…>]

An issue I've encountered when administering a Trac project is that permissions remain assigned to users and groups after the plugin that registers the permission has been removed, which presents a confusing view and makes manual cleanup a bit difficult. I've seen one user on the mailing list get confused by the permission being defined for a user and therefore they expected the permission to have its effect, even though the plugin was no longer loading.

The proposal is to use the light grey color that is used for a missing link, to indicate that a permission is not valid. It will make cleanup after a plugin uninstall easier.