Method with array-values as default parameter ends in invalid tag

I'm not sure if it's a bug or maybe the notation is not allowed. But this example here:

```
/**
 * @method mixed randomElement(array $array = array('a', 'b', 'c'))
 */
class Generator
{

}
```

ends up in an invalid tag with the message:

> "\'b'" is not a valid Fqsen.