bug symfony#21032 [SecurityBundle] Made collection of user provider unique when injecting them to the RemberMeService (lyrixx)

This PR was merged into the 2.7 branch.

Discussion
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[SecurityBundle] Made collection of user provider unique when injecting them to the RemberMeService

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Commits
-------

8227593 [SecurityBundle] Made collection of user provider unique when injecting them to the RemberMeService

Author: fabpot

src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/RememberMeFactory.php

@@ -96,7 +96,8 @@ public function create(ContainerBuilder $container, $id, $config, $userProvider,
         if (count($userProviders) === 0) {
             throw new \RuntimeException('You must configure at least one remember-me aware listener (such as form-login) for each firewall that has remember-me enabled.');
         }
-        $rememberMeServices->replaceArgument(0, $userProviders);
+
+        $rememberMeServices->replaceArgument(0, array_unique($userProviders));
 
         // remember-me listener
         $listenerId = 'security.authentication.listener.rememberme.'.$id;