bug #32682 [HttpFoundation] Revert getClientIp @return docblock (ossi…

…nkine)

This PR was merged into the 3.4 branch.

Discussion
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[HttpFoundation] Revert getClientIp @return docblock

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| License       | MIT

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This PR reverts #22418, see the comment #22418 (comment)

Commits
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7568d34 [HttpFoundation] Revert getClientIp @return docblock

src/Symfony/Component/HttpFoundation/Request.php

@@ -912,7 +912,7 @@ public function getClientIps()
      * ("Client-Ip" for instance), configure it via the $trustedHeaderSet
      * argument of the Request::setTrustedProxies() method instead.
      *
-     * @return string|null The client IP address
+     * @return string The client IP address
      *
      * @see getClientIps()
      * @see http://en.wikipedia.org/wiki/X-Forwarded-For