[Security] Added target user to SwitchUserListener

[javiereguiluz]

This adds the target user to the SwitchUserListener's accessDecisionManager->decide() call as the $object parameter to give any registered voters extra information.

See symfony/symfony#25092

[jwmickey]

As the author of this new feature I have a working use-case and would like to contribute the docs. Should this be appended to the impersonating_user.html file or does it need it's own page?

[xabbuh]

I think the existing article is a good place to add this.

[jwmickey]

I submitted a PR for an example: #9353

I pushed this to the master branch. Would that be why the platform.sh check was not created?

[xabbuh]

I don't think that is related. It happens from time to time that builds are not triggered on platform.sh. I guess we need to check the logs. But thanks for notifying us anyway. 👍

[javiereguiluz]

Closing as fixed by #9353.