Require doctrine/persistence 2

This allows us to remove autoload calls that are necessary for the
persistence 1 backwards-compatibility layer to work.
The require-dev constraints on doctrine/orm are bumped to ^2.7.3 because
lower versions are not compatible with doctrine/persistence 2.

composer.json

@@ -19,7 +19,7 @@
         "php": ">=7.2.5",
         "ext-xml": "*",
         "doctrine/event-manager": "~1.0",
-        "doctrine/persistence": "^1.3|^2",
+        "doctrine/persistence": "^2",
         "twig/twig": "^2.10|^3.0",
         "psr/cache": "~1.0",
         "psr/container": "^1.0",
@@ -116,7 +116,7 @@
         "doctrine/collections": "~1.0",
         "doctrine/data-fixtures": "^1.1",
         "doctrine/dbal": "^2.10|^3.0",
-        "doctrine/orm": "~2.4,>=2.4.5",
+        "doctrine/orm": "^2.7.3",
         "doctrine/doctrine-bundle": "^2.0",
         "guzzlehttp/promises": "^1.3.1",
         "masterminds/html5": "^2.6",

src/Symfony/Bridge/Doctrine/Form/Type/DoctrineType.php

@@ -269,5 +269,3 @@ abstract class DoctrineType extends AbstractType implements ResetInterface
         return $this->entityLoaders[$hash] ?? ($this->entityLoaders[$hash] = $this->getLoader($manager, $queryBuilder, $class));
     }
 }
-
-interface_exists(ObjectManager::class);

src/Symfony/Bridge/Doctrine/Form/Type/EntityType.php

@@ -96,5 +96,3 @@ class EntityType extends DoctrineType
         return [$parameter->getName(), $parameter->getType(), $parameter->getValue()];
     }
 }
-
-interface_exists(ObjectManager::class);

src/Symfony/Bridge/Doctrine/Security/User/EntityUserProvider.php

@@ -153,6 +153,3 @@ class EntityUserProvider implements UserProviderInterface, PasswordUpgraderInter
         return $this->getObjectManager()->getClassMetadata($this->classOrAlias);
     }
 }
-
-interface_exists(ObjectManager::class);
-interface_exists(ObjectRepository::class);

src/Symfony/Bridge/Doctrine/composer.json

@@ -18,7 +18,7 @@
     "require": {
         "php": ">=7.2.5",
         "doctrine/event-manager": "~1.0",
-        "doctrine/persistence": "^1.3|^2",
+        "doctrine/persistence": "^2",
         "symfony/polyfill-ctype": "~1.8",
         "symfony/polyfill-mbstring": "~1.0",
         "symfony/polyfill-php80": "^1.15",
@@ -48,7 +48,7 @@
         "doctrine/collections": "~1.0",
         "doctrine/data-fixtures": "^1.1",
         "doctrine/dbal": "^2.10|^3.0",
-        "doctrine/orm": "^2.6.3"
+        "doctrine/orm": "^2.7.3"
     },
     "conflict": {
         "doctrine/dbal": "<2.10",