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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

nextRoot = root;
    nextRenderExpirationTime = expirationTime;
    nextUnitOfWork = createWorkInProgress(
      nextRoot.current,
      null,
      nextRenderExpirationTime,
    );
    root.pendingCommitExpirationTime = NoWork;
    if (enableSchedulerTracing) {
      // 
      // 
      // 
      const interactions: Set<Interaction> = new Set();
      root.pendingInteractionMap.forEach(
        (scheduledInteractions, scheduledExpirationTime) => {
          if (scheduledExpirationTime >= expirationTime) {
            scheduledInteractions.forEach(interaction =>
              interactions.add(interaction),
            );
          }
        },
      );
      // 
      // 
      // 
      // 
      root.memoizedInteractions = interactions;
      if (interactions.size > 0) {
        const subscriber = __subscriberRef.current;
        if (subscriber !== null) {