*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


node.defaultValue = node.innerHTML.replace(/^\n/, '');
      return node;
    };
  });
  it('should allow setting `defaultValue`', () => {
    const container = document.createElement('div');
    const node = renderTextarea(<textarea defaultValue="giraffe" />, container);
    expect(node.value).toBe('giraffe');
    
    renderTextarea(<textarea defaultValue="gorilla" />, container);
    expect(node.value).toEqual('giraffe');
    node.value = 'cat';
    renderTextarea(<textarea defaultValue="monkey" />, container);
    expect(node.value).toEqual('cat');
  });
  it('should display `defaultValue` of number 0', () => {
    const stub = <textarea defaultValue={0} />;
    const node = renderTextarea(stub);
    expect(node.value).toBe('0');
  });
  it('should display "false" for `defaultValue` of `false`', () => {
    const stub = <textarea defaultValue={false} />;
    const node = renderTextarea(stub);
    expect(node.value).toBe('false');
  });
  it('should display "foobar" for `defaultValue` of `objToString`', () => {
    const objToString = {
      toString: function() {