Merge branch '7.4' into 8.0

* 7.4:
  [FrameworkBundle] Dump all registered extensions’ configuration reference
  fix merge
  Mark FormFlow as finished if the last step is skipped
  [HttpKernel] Fix using MapRequestPayload on nullable arguments
  [ObjectMapper] bypass lazy ghost with class transform
  [WebProfilerBundle] fix displaying runner
  [DependencyInjection] Fix preloading LazyClosure
  [Emoji] Update list to version 17
  make doLoadClassMetadata() methods private
  fix routing config type information
  [HttpClient] Don't reset unused clients in data collector

Author: nicolas-grekas

Mapping/Loader/AttributeLoader.php

@@ -75,7 +75,7 @@ public function loadClassMetadata(ClassMetadataInterface $classMetadata): bool
         return $success;
     }
 
-    public function doLoadClassMetadata(\ReflectionClass $reflectionClass, ClassMetadataInterface $classMetadata): bool
+    private function doLoadClassMetadata(\ReflectionClass $reflectionClass, ClassMetadataInterface $classMetadata): bool
     {
         $className = $reflectionClass->name;
         $loaded = false;