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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

ReactNoop.yield('componentDidMount');
        }
        render() {
          ReactNoop.yield(this.state.text);
          return <span prop={this.state.text} />;
        }
      }
      ReactNoop.renderLegacySyncRoot(
        <Suspense fallback={<Text text="Loading..." />}>
          <AsyncTextInConstructor ms={100} text="Hi" />
        </Suspense>,
      );
      expect(ReactNoop.clearYields()).toEqual([
        'constructor',
        'Suspend! [Hi]',
        'Loading...',
      ]);
      expect(ReactNoop.getChildren()).toEqual([span('Loading...')]);
      await advanceTimers(1000);
      expect(ReactNoop.clearYields()).toEqual([
        'Promise resolved [Hi]',
        'constructor',
        'Hi',
        'componentDidMount',
      ]);
      expect(ReactNoop.getChildren()).toEqual([span('Hi')]);
    });
    it('does not infinite loop if fallback contains lifecycle method', async () => {
      class Fallback extends React.Component {