Small comment update according to PSR-2
Small comment update according to PSR-2

See [PSR-2](http://www.php-fig.org/psr/psr-2/) paragraph 5.2

> There MUST be a comment such as `// no break` when fall-through is intentional in a non-empty case body.

Related to #11181

ygerasimov/HttpFoundation,symfony/http-foundation,nichdu/HttpFoundation,oswaldderiemaecker/HttpFoundation,mneuhaus/HttpFoundation,symfony/HttpFoundation