Follow up from https://github.com/facebook/react/pull/11616.

Here's one I found. These two invariants:

https://github.com/facebook/react/blob/7e7127387ba64f57299eaff8656542cea6fb3a2d/packages/react-reconciler/src/ReactFiberClassComponent.js#L330-L343

are in a function that's behind a DEV block:

https://github.com/facebook/react/blob/7e7127387ba64f57299eaff8656542cea6fb3a2d/packages/react-reconciler/src/ReactFiberClassComponent.js#L447-L449

I don't think this is intentional, but need to verify.

There may be more. I'll use this issue to track while https://github.com/facebook/react/pull/11616 preserves existing behavior.
},
    };
    if (shouldConstruct(Component)) {
      inst = new Component(element.props, publicContext, updater);
    } else {
      inst = Component(element.props, publicContext, updater);
      if (inst == null || inst.render == null) {
        child = inst;
        validateRenderResult(child, Component);
        continue;
      }
    }
    inst.props = element.props;
    inst.context = publicContext;
    inst.updater = updater;
    var initialState = inst.state;
    if (initialState === undefined) {
      inst.state = initialState = null;
    }
    if (inst.componentWillMount) {
      inst.componentWillMount();
      if (queue.length) {
        var oldQueue = queue;
        var oldReplace = replace;
        queue = null;
        replace = false;
        if (oldReplace && oldQueue.length === 1) {
          inst.state = oldQueue[0];
        } else {
          var nextState = oldReplace ? oldQueue[0] : inst.state;