Item12952: Don't NOT_SET keys that are UNDEFINEDOK

Older configurations that don't use short URLs probably won't have
{ScriptUrlPaths}{view} defined.  Since that key is UNDEFINEDOK, don't
initialize it to "NOT SET" and invalidate the configuration.

The Save Wizard however uses this same list and the variables to
preserve from bootstrap, so we can't just remove it from the list.