Long story short: this is required to allow preserve initial alias after `clear()` for queries created by `ModelCriteria::create()

see https://github.com/alanbem/Propel/blob/cd22e0bbc2a9ec14c0fa3d72abe6020074ac1997/test/testsuite/runtime/query/ModelCriteriaTest.php#L2593

At the same time this change is backward compatible with possible custom query objects like 

```php

class CustomAuthorQuery extends ModelCriteria
{
    public function __construct($dbName = 'bookstore', $modelName = 'NOT_DEFAULT_MODEL_NAME', $modelAlias = null)
    {
        parent::__construct($dbName, $modelName, $modelAlias);
    }
}
```