Fix merge

Author: nicolas-grekas

PropertyInfo/DoctrineExtractor.php

@@ -202,7 +202,7 @@ private function getMetadata(string $class): ?ClassMetadata
     {
         try {
             return $this->entityManager ? $this->entityManager->getClassMetadata($class) : $this->classMetadataFactory->getMetadataFor($class);
-        } catch (MappingException | OrmMappingException $exception) {
+        } catch (MappingException | OrmMappingException | LegacyMappingException $exception) {
             return null;
         }
     }

Tests/Form/ChoiceList/DoctrineChoiceLoaderTest.php

@@ -408,7 +408,7 @@ public function testLoaderWithoutIdReaderCanBeOptimized()
             })
         ;
 
-        $this->om = $this->createMock(ObjectManager::class);
+        $this->om = $this->createMock(interface_exists(ObjectManager::class) ? ObjectManager::class : LegacyObjectManager::class);
         $this->om->expects($this->once())
             ->method('getClassMetadata')
             ->with(SingleIntIdEntity::class)