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.
return <span className="foo" />;
      }
    }
    test(<NamedComponent />, 'SPAN', 'foo');
    if (__DEV__) {
      expect(console.error.calls.count()).toBe(1);
      expect(console.error.calls.argsFor(0)[0]).toBe(
        'Warning: ' +
          'NamedComponent has a method called componentWillRecieveProps(). Did ' +
          'you mean componentWillReceiveProps()?',
      );
    }
  });
  it('should throw AND warn when trying to access classic APIs', () => {
    spyOnDev(console, 'warn');
    var instance = test(<Inner name="foo" />, 'DIV', 'foo');
    expect(() => instance.replaceState({})).toThrow();
    expect(() => instance.isMounted()).toThrow();
    if (__DEV__) {
      expect(console.warn.calls.count()).toBe(2);
      expect(console.warn.calls.argsFor(0)[0]).toContain(
        'replaceState(...) is deprecated in plain JavaScript React classes',
      );
      expect(console.warn.calls.argsFor(1)[0]).toContain(
        'isMounted(...) is deprecated in plain JavaScript React classes',
      );
    }
  });
  it('supports this.context passed via getChildContext', () => {
    class Bar extends React.Component {