Fix global object ref in core package's output
Fix global object ref in core package's output

Without the parenthesis this resulted in invalid code
```
var chunkLoadingGlobal = typeof self !== 'undefined' ? self : this["webpackChunkngHotReloadCore"] =
```

See https://github.com/webpack/webpack/issues/12924

noppa/ng-hot-reload,noppa/ng-hot-reload,noppa/ng-hot-reload