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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

{unstable_isConcurrent: true},
          );
          
          
          
          expect(renderer).toFlushAndYield([
            'FirstComponent:1',
            'Yield:4',
            'SecondComponent:2',
            'Yield:7',
          ]);
          expect(callback).toHaveBeenCalledTimes(1);
          let call = callback.mock.calls[0];
          expect(call[2]).toBe(14); 
          expect(call[3]).toBe(14); 
          expect(call[4]).toBe(5); 
          expect(call[5]).toBe(19); 
          callback.mockClear();
          advanceTimeBy(100); 
          
          
          first.setState({renderTime: 10});
          expect(renderer).toFlushAndYieldThrough(['FirstComponent:10']);
          expect(callback).toHaveBeenCalledTimes(0);
          
          advanceTimeBy(100); 
          
          
          renderer.unstable_flushSync(() => second.setState({renderTime: 30}));
          expect(ReactTestRenderer).toHaveYielded([