Remove blank fields from a bound form

gistfile1.aw

<?php
// ...
        $formData = $request->request->get('splashmedia_bundle_oxygenbundle_usertype');
        if ( 0 === strlen( $formData['expiresAt']['date']['year'] ) ) {
            $editForm->remove( 'expiresAt' );
            unset( $formData['expiresAt']);
        }
        if ( 0 === strlen( $formData['passwordRequestedAt']['date']['year'] ) ) {
            $editForm->remove( 'passwordRequestedAt' );
            unset( $formData['passwordRequestedAt']);
        }
        $request->request->set( 'splashmedia_bundle_oxygenbundle_usertype', $formData );