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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

unhideInstance,
  unhideTextInstance,
} from './ReactFiberHostConfig';
import {
  captureCommitPhaseError,
  flushPassiveEffects,
  requestCurrentTime,
  scheduleWork,
} from './ReactFiberScheduler';
import {
  NoEffect as NoHookEffect,
  UnmountSnapshot,
  UnmountMutation,
  MountMutation,
  UnmountLayout,
  MountLayout,
  UnmountPassive,
  MountPassive,
} from './ReactHookEffectTags';
let didWarnAboutUndefinedSnapshotBeforeUpdate: Set<mixed> | null = null;
if (__DEV__) {
  didWarnAboutUndefinedSnapshotBeforeUpdate = new Set();
}
export function logError(boundary: Fiber, errorInfo: CapturedValue<mixed>) {
  const source = errorInfo.source;
  let stack = errorInfo.stack;
  if (stack === null && source !== null) {
    stack = getStackByFiberInDevAndProd(source);
  }
  const capturedError: CapturedError = {