<!--
  Note: if the issue is about documentation or the website, please file it at:
  https://github.com/reactjs/reactjs.org/issues/new
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**Do you want to request a *feature* or report a *bug*?**

bug.

**What is the current behavior?**

```js
  renderer.create(
    <Fragment>
      <Fragment>foo</Fragment>
    </Fragment>
  )
  .toTree()
```

> Invariant Violation: toTree() does not yet know how to handle nodes with tag=10

https://codesandbox.io/s/olky92m01y

**What is the expected behavior?**

returns a tree.

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**

16.2.0

if (!node) {
    return;
  }
  if (Array.isArray(node)) {
    node.forEach(cleanNodeOrArray);
    return;
  }
  if (node && node.instance) {
    node.instance = null;
  }
  if (node && node.props && node.props.children) {
    
    const {children, ...props} = node.props;
    node.props = props;
  }
  if (Array.isArray(node.rendered)) {
    node.rendered.forEach(cleanNodeOrArray);
  } else if (typeof node.rendered === 'object') {
    cleanNodeOrArray(node.rendered);
  }
}
describe('ReactTestRenderer', () => {
  it('renders a simple component', () => {
    function Link() {