code: function handleLocationChange(location) {
      // ... unless we just caused that location change
      if (isTimeTraveling) {
        return;
      }
  
      // Remember where we are
      currentLocation = location;
  
      // Are we being called for the first time?
      if (!initialLocation) {
        // Remember as a fallback in case state is reset
        initialLocation = location;
  
        // Respect persisted location, if any
        if (getLocationInStore()) {
          return;
        }
      }
  
      // Tell the store to update by dispatching an action
      store.dispatch({
        type: _reducer.LOCATION_CHANGE,
        payload: location
      });
    }
docs: Whenever location changes, dispatch an action to get it in the store