Update region if it has changed after rendering footer (bug 1066774)

Follow-up to #663 
https://bugzilla.mozilla.org/show_bug.cgi?id=1066774

We do wait for the consumer info promise before triggering 'navigate', so the region in the views is OK, but the footer can be rendered before that.


`if 'rest of world' != old_region`? I'm confused