Observed this on react@16.0.0-beta.5

```js
import React from 'react';
import { renderToString } from 'react-dom/server';

const B = () => 'b';

console.log(renderToString(<div>{'a'}<B />{'c'}</div>));
```

This renders as `<div data-reactroot="">a<!-- -->bc</div>`. If you try to hydrate this you'll get the error: Text content did not match. Server: "bc" Client: "b".
<select value={['bar', 'baz']} multiple={true} readOnly={true}>
              {options}
            </select>,
          );
          expectSelectValue(e, ['bar', 'baz']);
        },
      );
      itRenders(
        'a select with a value and no onChange/readOnly',
        async render => {
          
          
          const e = await render(<select value="bar">{options}</select>, 1);
          expectSelectValue(e, 'bar');
        },
      );
      itRenders('a select with a defaultValue', async render => {
        const e = await render(<select defaultValue="bar">{options}</select>);
        expectSelectValue(e, 'bar');
      });
      itRenders('a select value overriding defaultValue', async render => {
        const e = await render(
          <select value="bar" defaultValue="baz" readOnly={true}>
            {options}
          </select>,
          1,
        );
        expectSelectValue(e, 'bar');
      });
      itRenders(