State consistency, url => components + state

Included in navigableMixin, the initialState of a component check for
the route.

For now, we have to delegate route :

for url /route/subroute we want to have View A (/) which include View B
(/route) which include View C (/route/subroute)
We have to tell A to delegate /route/subroute to B
route: {
  /route: B
  /route/subroute: B
}