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**Do you want to request a *feature* or report a *bug*?** Bug, I guess

**What is the current behavior?** 


```
  console.error node_modules/fbjs/lib/warning.js:33
    Warning: Detected multiple renderers concurrently rendering the same context provider. This is currently unsupported.
```

Steps to reproduce the behavior:
1. `git clone https://github.com/stereobooster/react-context-issue`
2. `cd react-context-issue`
3. `yarn`
4. `yarn test`

**What is the expected behavior?** no warning

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?** React 16.4. Browser not affected, because error is in node.js

Open this because of https://github.com/facebook/react/pull/13127#issuecomment-402527012

Issue happens because of Enzyme (https://github.com/airbnb/enzyme/issues/1693), code is unreleased, so I copy-pasted it from master. 

I'm looking for advice or some clue on how to fix this, so I would be able to create PR in Enzyme repo (or in React repo if this is the case). Thank you.


log.push('Boundary componentDidMount');
      }
      componentWillUnmount() {
        log.push('Boundary componentWillUnmount');
      }
      onClick() {
        
      }
      componentDidCatch() {
        log.push('Boundary componentDidCatch');
        this.setState({error: true});
      }
    }
    const renderer = ReactTestRenderer.create(<Boundary />);
    expect(renderer.toJSON()).toEqual({
      type: 'div',
      props: {},
      children: ['Happy Birthday!'],
    });
    expect(log).toEqual([
      'Boundary render',
      'Angry render',
      'Boundary componentDidMount',
      'Boundary componentDidCatch',
      'Boundary render',
    ]);
  });
  it('can update text nodes', () => {
    class Component extends React.Component {