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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

loadModules({enableSchedulerTracing});
      });
      it('should handle errors thrown', () => {
        const callback = jest.fn(id => {
          if (id === 'throw') {
            throw Error('expected');
          }
        });
        let didMount = false;
        class ClassComponent extends React.Component {
          componentDidMount() {
            didMount = true;
          }
          render() {
            return this.props.children;
          }
        }
        
        
        expect(() =>
          ReactTestRenderer.create(
            <ClassComponent>
              <React.unstable_Profiler id="do-not-throw" onRender={callback}>
                <React.unstable_Profiler id="throw" onRender={callback}>
                  <div />
                </React.unstable_Profiler>
              </React.unstable_Profiler>
            </ClassComponent>,
          ),
        ).toThrow('expected');