<!--
  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, 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.


tag: 'TEXT',
|};
export type HydratableInstance = Instance | TextInstance;
export type PublicInstance = Instance | TextInstance;
export type HostContext = Object;
export type UpdatePayload = Object;
export type ChildSet = void; 
export type TimeoutHandle = TimeoutID;
export type NoTimeout = -1;
export * from 'shared/HostConfigWithNoPersistence';
export * from 'shared/HostConfigWithNoHydration';
const NO_CONTEXT = {};
const UPDATE_SIGNAL = {};
if (__DEV__) {
  Object.freeze(NO_CONTEXT);
  Object.freeze(UPDATE_SIGNAL);
}
export function getPublicInstance(inst: Instance | TextInstance): * {
  switch (inst.tag) {
    case 'INSTANCE':
      const createNodeMock = inst.rootContainerInstance.createNodeMock;
      return createNodeMock({
        type: inst.type,
        props: inst.props,
      });
    default:
      return inst;
  }
}
export function appendChild(