Merge branch '4.4' into 5.1

* 4.4:
  fail properly when the required service is not defined
  Fix typo
  [Finder] Fix GitIgnore parser when dealing with (sub)directories and take order of lines into account
  Update UPGRADE-5.0.md
  Added the missing reset tag to mailer.logger_message_listener
  Updated README for the Mailer component
  fix error with custom function and web profiler routing tab

Author: fabpot

Resources/config/mailer.xml

@@ -41,6 +41,7 @@
 
         <service id="mailer.logger_message_listener" class="Symfony\Component\Mailer\EventListener\MessageLoggerListener">
             <tag name="kernel.event_subscriber"/>
+            <tag name="kernel.reset" method="reset" />
         </service>
     </services>
 </container>

Test/MailerAssertionsTrait.php

@@ -118,10 +118,10 @@ public static function getMailerMessage(int $index = 0, string $transport = null
 
     private static function getMessageMailerEvents(): MessageEvents
     {
-        if (!$logger = self::$container->get('mailer.logger_message_listener')) {
+        if (!self::$container->has('mailer.logger_message_listener')) {
             static::fail('A client must have Mailer enabled to make email assertions. Did you forget to require symfony/mailer?');
         }
 
-        return $logger->getEvents();
+        return self::$container->get('mailer.logger_message_listener')->getEvents();
     }
 }