symfony/symfony — pull request #5282 by Tobion (2012-08-17 00:23:05+00:00)
Title: [HttpFoundation] fixed undefined offset for assoc arrays in HeaderBag

`get` is assuming the headers are zero-indexed. So something like this would otherwise create a php warning.
```
$bag->set('foo', array('bad-assoc-index' => 'value'));
$this->assertSame('value', $bag->get('foo'));
```