Allow the internal login form to be in a collapsible area if there are
both internal and external login options

Don't show the generic 'fields are required' message when internal
form is hidden in collapse field

behatnotneeded

Change-Id: Ib097f5f33c9f9a85bc91bdd88df04e21d9c1a3e3
Signed-off-by: Robert Lyon <robertl@catalyst.net.nz>