Ensure the execute() method returns a valid response on 405 exceptions.
public function test405HTML() {
$exception = new \Exception('Test exception');
$flat_exception = FlattenException::create($exception, 405);
$exception_controller = new ExceptionController(new ContentNegotiation());
$response = $exception_controller
->execute($flat_exception, new Request());
$this
->assertEqual($response
->getStatusCode(), 405, 'HTTP status of response is correct.');
$this
->assertEqual($response
->getContent(), 'Method Not Allowed', 'HTTP response body is correct.');
}