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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

render() {
            return this.props.children;
          }
        }
        const renderer = ReactTestRenderer.create(
          <React.unstable_Profiler id="outer" onRender={callback}>
            <Updater>
              <React.unstable_Profiler id="middle" onRender={callback}>
                <Pure>
                  <React.unstable_Profiler id="inner" onRender={callback}>
                    <div />
                  </React.unstable_Profiler>
                </Pure>
              </React.unstable_Profiler>
            </Updater>
          </React.unstable_Profiler>,
        );
        
        expect(callback).toHaveBeenCalledTimes(3);
        callback.mockReset();
        renderer.unstable_flushSync(() => {
          instance.setState({
            count: 1,
          });
        });