…erializer default id (ogizanagi)This PR was merged into the 4.2 branch.Discussion----------[FrameworkBundle][Messenger] Restore check for messenger serializer default id| Q             | A| ------------- | ---| Branch?       | 4.2 <!-- see below -->| Bug fix?      | yes| New feature?  | no <!-- don't forget to update src/**/CHANGELOG.md files -->| BC breaks?    | no     <!-- seehttps://symfony.com/bc -->| Deprecations? | no <!-- don't forget to update UPGRADE-*.md and src/**/CHANGELOG.md files -->| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->| Fixed tickets |https://symfony-devs.slack.com/archives/C9PQ75TV3/p1543590611003500  <!-- #-prefixed issue number(s), if any -->| License       | MIT| Doc PR        | N/AFrom Slack:>@adamquaile [4:10 PM]> So, I just updated to 4.2 today, and got this message:> > The default Messenger serializer cannot be enabled as the Serializer support is not available. Try enabling it or running "composer require symfony/serializer-pack">> In the docs it's stated:> > In order to use Symfony's built-in AMQP transport, you will need the Serializer Component. Ensure that it is installed with:>>But I haven't yet configured AMQP - I'm using my own transport. Should I be getting this exception?---This check was removed in#28405, but is actually still necessary to not fail as soon as you can install the Messenger component without the Serializer one installed.Commits-------1cf17c0 [FrameworkBundle][Messenger] Restore check for messenger serializer default id