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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

state = {
          name: 'foo',
        };
        componentDidMount() {
          this.setState({
            name: 'bar',
          });
        }
        render() {
          return <Text text="Loading..." />;
        }
      }
      class Demo extends React.Component {
        render() {
          return (
            <Suspense fallback={<Fallback />}>
              <AsyncText text="Hi" ms={100} />
            </Suspense>
          );
        }
      }
      ReactNoop.renderLegacySyncRoot(<Demo />);
      expect(ReactNoop.getChildren()).toEqual([span('Loading...')]);
      await advanceTimers(100);
      expect(ReactNoop.getChildren()).toEqual([span('Hi')]);
    });
  });
  it('does not call lifecycles of a suspended component', async () => {
    class TextWithLifecycle extends React.Component {