Now that @twpayne reminded me of the fact that `ol.xml.pushParseAndPop` can indeed return `undefined` in the case of an error, there should be no type cast on the return value. Instead, the `else` block should go away, and something like this would be done:
```js
if (!goog.isDef(features) {
  features = [];
}
return features;
```
Sorry, my bad.