*Bug*

When a `textarea` has the `required` attribute it renders in the invalid state using FireFox. 

This behavior is visible here: https://codesandbox.io/s/rough-frog-f00ow. Remember to view it in FireFox.  

I expect the required field to validate on form submit and not before. 

I have tested this with FireFox 68 and 69 and React 16.8.6

This appears appears to be a re-occurrence of: https://github.com/facebook/react/issues/8395


if (__DEV__) {
        warning(
          false,
          'Use the `defaultValue` or `value` props instead of setting ' +
            'children on <textarea>.',
        );
      }
      invariant(
        defaultValue == null,
        'If you supply `defaultValue` on a <textarea>, do not pass children.',
      );
      if (Array.isArray(children)) {
        invariant(
          children.length <= 1,
          '<textarea> can only have at most one child.',
        );
        children = children[0];
      }
      defaultValue = children;
    }
    if (defaultValue == null) {
      defaultValue = '';
    }
    initialValue = defaultValue;
  }
  node._wrapperState = {
    initialValue: getToStringValue(initialValue),
  };
}
export function updateWrapper(element: Element, props: Object) {