Constants polyfill mixes named and default exports, breaks graceful-fs

I've found that when named and default exports are mixed, the helper function `getDefaultExportFromNamespaceIfNotNamed` doesn't work correctly, it's defined as:

```
function getDefaultExportFromNamespaceIfNotNamed (n) {
return n && Object.prototype.hasOwnProperty.call(n, 'default') && Object.keys(n).length === 1 ? n['default'] : n;
}
```

Which means that code being compiled would need to import the `default` key specifically. This is mentioned here as well: https://rollupjs.org/guide/en/#outputexports.

The spot I'm seeing this cause problems is with `graceful-fs`. It has an `var constants = require('constants');`, and then later on it does a check for `constants.hasOwnProperty('O_SYMLINK')`, which blows up because it's treating the import as a `import * as constants`, which doesn't have `hasOwnProperty` and thus blows up.

I'm not sure what the right approach is, other than maybe only exporting a default object? Does node.js support `import {ENETDOWN} from 'constants'?