No validation UI for some form elements

[CarlosNZ]

I.e. there's no visual indicator for the user when they've failed to complete the element.

In particular (add to this list as we check them):

• fileUpload
• password

This is mainly because we're not using a standard "form" component (e.g. "input"), which has an "error" state. So for these ones we'll need to implement our own error UI for them.