dvAdminHiddenHeaders top-level constant
The headers a hidden request is answered with.
Nothing that names the admin. A WWW-Authenticate here, or a body that
mentions a studio, gives away in one response everything the status code
was chosen to withhold.
Implementation
const Map<String, String> dvAdminHiddenHeaders = <String, String>{
'content-type': 'text/plain; charset=utf-8',
};