*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


<div>
            <form className="container">
              <fieldset>
                <legend>Controlled</legend>
                <textarea value={this.state.value} onChange={this.onChange} />
              </fieldset>
              <fieldset>
                <legend>Uncontrolled</legend>
                <textarea defaultValue="" />
              </fieldset>
            </form>
            <div className="container">
              <h4>Controlled Output:</h4>
              <div className="output">{this.state.value}</div>
            </div>
          </div>
        </TestCase>
        <TestCase title="Placeholders">
          <TestCase.ExpectedResult>
            The textarea should be rendered with the placeholder "Hello, world"
          </TestCase.ExpectedResult>
          <div style={{margin: '10px 0px'}}>
            <textarea placeholder="Hello, world" />
          </div>
        </TestCase>
      </FixtureSet>
    );
  }
}