I'm trying to express an admittedly fairly complex type, where it has to have at least one of two properties, if it has a certain property, it must have another property, etc. However, I'm getting weird errors.

Here's the type
```js
export type learningItemT = {
name: string,
id: string
} & (
| { dataStructure: any, Editor: React.ComponentType }
| { Creator: React.ComponentType, Editor?: React.ComponentType }
) &
(
| {
ThumbViewer: React.ComponentType,
Viewer?: React.ComponentType
}
| {
ThumbViewer?: React.ComponentType,
Viewer: React.ComponentType
}
);
```

When I declare an element, I get no errors.

```js
const f = () =>

Hi

const f1 = () =>

Hi

const f2 = () =>

Hi

const a = ({
name: 'file',
id: 'li-file',
Viewer: f,
ThumbViewer: f1,
Creator: f2
}: learningItemT);
```

However, when I try to access Creator, which is a valid member of the type above (otherwise the assignment should already have failed?), it doesn't let me:

```js
if(a.Creator) { console.log(a.Creator) }
```

(Flow error)

If I isolate this single union type, and do exactly the same, it works perfectly (no errors):

```js
type c = (
| { dataStructure: any, Editor: React.ComponentType }
| { Creator: React.ComponentType, Editor?: React.ComponentType }
)

const newtry: c = {Creator: f1}
if(newtry.Creator) { console.log('this time it worked') }
```

https://flow.org/try/#0PQKgBAAgZgNg9gdzCYAoVBLAtgBzgJwBdkwBDAZzACUBTUgY2KnzizAHJ87H2BudGgA88RMIQCeOGmBh18AOwzyA5gElCNLABUwAXjABvVGDDzSWGgC4w5QviXKANMbAYAJtdv2VqAL5gAMjAAChcAH0MwN1JCUgBlOwBXRkSua1J5cUcwAFE3DEICa1oGQgA6AGFWPHkaeUItSRoAHgzxAD4wX3DIiq4YoupucqrcOFr6xqlWzPbsvIKCAH5i4crq8bqGppmOrtQASkCXUJMTCKMzq7AtAAtErAAjADUMGgQafFXS9bGJ7embTmLmuYFe70+KyGP1GNS2UxaQJBZ26VwuyKudweLzeH3wUJKjF+cMmOyBzlBJnBeO+RNhm1JgNmGP2JgO-FQ9HGtjAUD0ISOuk6zVuAEZ2gAJDDNYBi9qc7lMUX84KC4VyqUyuUK+Q8qAAJhVarAIvFmtl4vQXN1xFI-JCl1M5isHCgGFk7Aprg8HBgGAAtG6PV7qZ9rFAvVinqGvrzRV6+nRCrGDX5rLJSAoHOpNFp2egMFBgqRKv1k0cDGBreQ4LIyvBlMXS0mCEdusYJFIqyqepXorEEvhkoRUi62vN8snaSMNv8EbtOqiwBcwImBrHCTO-vCybMJ4t8dPiQyAYjZvsDlbFaZ3nZxNZ6PyDGup3HuoXgrUEHfm+uK1XuVrGh6zgRt2EIW4MEoQhsGkAowAQAgAGsaDcdg2yAA