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

'It is not supported to run the profiling version of a renderer (for example, `react-dom/profiling`) ' +
      'without also replacing the `schedule/tracing` module with `schedule/tracing-profiling`. ' +
      'Your bundler might have a setting for aliasing both modules. ' +
      'Learn more at http://fb.me/react-profiling',
  );
}
if (__DEV__) {
  didWarnAboutStateTransition = false;
  didWarnSetStateChildContext = false;
  const didWarnStateUpdateForUnmountedComponent = {};
  warnAboutUpdateOnUnmounted = function(fiber: Fiber, isClass: boolean) {
    
    
    const componentName = getComponentName(fiber.type) || 'ReactComponent';
    if (didWarnStateUpdateForUnmountedComponent[componentName]) {
      return;
    }
    warningWithoutStack(
      false,
      "Can't perform a React state update on an unmounted component. This " +
        'is a no-op, but it indicates a memory leak in your application. To ' +
        'fix, cancel all subscriptions and asynchronous tasks in %s.%s',
      isClass
        ? 'the componentWillUnmount method'
        : 'a useEffect cleanup function',
      ReactCurrentFiber.getStackByFiberInDevAndProd(fiber),
    );
    didWarnStateUpdateForUnmountedComponent[componentName] = true;
  };
  warnAboutInvalidUpdates = function(instance: React$Component<any>) {