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**Do you want to request a *feature* or report a *bug*?**
bug, I believe, unless I misunderstand how it works
**What is the current behavior?**
Given a `Suspense` inside `Suspense` case like
```
<Suspense fallback="Fallback 1">
  <LazyText1 text="First text" />
  <Suspense fallback="Fallback 2">
    <LazyText2 text="Second text!" />
  </Suspense>
</Suspense>
```

Promises in `LazyTexts` start resolving at the same time, but if `LazyText2` is resolved first it never renders, `Fallback 2` stays.

Result:
```
First text

Fallback 2
```

Please see https://codesandbox.io/s/234o4zry7n

**What is the expected behavior?**

Every `LazyText` displayed in the end
```
First text

Second text!
```

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
react, react-dom 16.6.0

const {duration, id} = this.props;
        return (
          <React.Fragment>
            <Child duration={duration} id={id} />
            <Child duration={duration} id={id} />
          </React.Fragment>
        );
      }
    }
    ReactNoop.advanceTime(50);
    ReactNoop.renderToRootWithID(<Parent duration={3} id="one" />, 'one');
    
    
    const commitFirstRender = ReactNoop.flushWithoutCommitting(
      ['Child:render:one', 'Child:render:one'],
      'one',
    );
    expect(ReactNoop.getRoot('one').current.actualDuration).toBe(0);
    ReactNoop.advanceTime(100);
    
    ReactNoop.renderToRootWithID(<Parent duration={7} id="two" />, 'two');
    ReactNoop.flushThrough(['Child:render:two']);
    ReactNoop.advanceTime(150);
    
    commitFirstRender(['Parent:componentDidMount:one']);
    expect(ReactNoop.getRoot('one').current.actualDuration).toBe(6);
    expect(ReactNoop.getRoot('two').current.actualDuration).toBe(0);
    ReactNoop.advanceTime(200);
    ReactNoop.flush();
    expect(ReactNoop.getRoot('two').current.actualDuration).toBe(14);