Recognise that view isn't in the hierarchy with flow.has

[dariocravero]

In this app flowhasissue.zip, when /App/Content is No, then the button on /App/EditOneAction shouldn't have isSelected set to true because /App/Content/Content/Edit/One isn't set.

What happens now is that because One is the default view in /App/Content/Content/Edit, it wins because of this https://github.com/viewstools/morph/blob/master/views/ViewsFlow.js#L104.

The expected behaviour would be that the flow.has method goes all the way up trying to find whether a parent of the view being checked is in fact in the flow, be it that it is a default view of an active path or not.

A workaround for now is to add a new view called No in /App/Content/Content/Edit.

Side note:
Since that'll be a recursive operation, it might be slow. Since these checks happen on every render I suggest that whenever we implement this we also consider adding a local cache to flow.has, something like this:

export function useFlow() {
  let state = useFlowState()

  return useMemo(() => {
    let _has = {}

    return {
      has: key => {
        if (!key) return false

        if (!(key in _has)) {
          _has[key] = calculate()
        }
        return _has[key]

        function calculate() {
          // ...the actual logic we have in there now plus the changes
        }
      },
      flow: state.flow,
    }
  }, [state.flow])
}

This will need to be tested for side effects with flow items with arguments (eg, a list gets a new item or the item gets removed) but in principle it should work as-is.