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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

expect(getWorkForReactThreads(onWorkStopped)).toHaveLength(0);
        
        
        
        expect(onWorkScheduled).toHaveBeenCalled();
        expect(onWorkScheduled.mock.calls[0][0]).toMatchInteractions([
          interactionOne,
        ]);
        expect(onWorkScheduled.mock.calls[0][1] > 0).toBe(true);
        expect(renderer).toFlushAndYieldThrough(['first']);
        expect(onRender).not.toHaveBeenCalled();
        expect(onInteractionTraced).toHaveBeenCalledTimes(2);
        expect(onInteractionTraced).toHaveBeenLastNotifiedOfInteraction(
          interactionOne,
        );
        expect(onInteractionScheduledWorkCompleted).toHaveBeenCalledTimes(1);
        expect(getWorkForReactThreads(onWorkStarted)).toHaveLength(1);
        expect(getWorkForReactThreads(onWorkStarted)[0][0]).toMatchInteractions(
          [interactionOne],
        );
        expect(getWorkForReactThreads(onWorkStopped)).toHaveLength(0);
        renderer.unstable_flushAll(['last']);
        expect(onRender).toHaveBeenCalledTimes(1);
        call = onRender.mock.calls[0];
        expect(call[0]).toEqual('test-profiler');
        expect(call[5]).toEqual(mockNow());
        if (ReactFeatureFlags.enableSchedulerTracing) {
          expect(call[6]).toMatchInteractions([interactionOne]);
        }
        didRunCallback = true;