<!--
  Note: if the issue is about documentation or the website, please file it at:
  https://github.com/reactjs/reactjs.org/issues/new
-->

**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

expect(getWorkForReactThreads(onWorkStarted)).toHaveLength(0);
      expect(getWorkForReactThreads(onWorkStopped)).toHaveLength(0);
      onRender.mockClear();
      advanceTimeBy(3);
      
      const interactionTwo = {
        id: 2,
        name: 'root update event',
        timestamp: mockNow(),
      };
      SchedulerTracing.unstable_trace(interactionTwo.name, mockNow(), () => {
        renderer.update(
          <React.unstable_Profiler id="test-profiler" onRender={onRender}>
            <Example />
          </React.unstable_Profiler>,
        );
      });
      expect(onInteractionTraced).toHaveBeenCalledTimes(3);
      expect(onInteractionTraced).toHaveBeenLastNotifiedOfInteraction(
        interactionTwo,
      );
      expect(onInteractionScheduledWorkCompleted).toHaveBeenCalledTimes(2);
      
      
      expect(getWorkForReactThreads(onWorkStarted)).toHaveLength(0);
      expect(getWorkForReactThreads(onWorkStopped)).toHaveLength(0);
      
      
      
      expect(onWorkScheduled).toHaveBeenCalled();