bug #58870 [Serializer][Validator] prevent failures around not existing TypeInfo classes (xabbuh)

This PR was merged into the 7.1 branch.

Discussion
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[Serializer][Validator] prevent failures around not existing TypeInfo classes

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        |
| License       | MIT

Having a `getType()` method on an extractor is not enough. Such a method may exist to be forward-compatible with the TypeInfo component. We still must not call it if the TypeInfo component is not installed to prevent running into errors for not-defined classes when the TypeInfo component is not installed.

Commits
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386453ee77b prevent failures around not existing TypeInfo classes

Author: nicolas-grekas

Mapping/Loader/PropertyInfoLoader.php

@@ -195,7 +195,7 @@ public function loadClassMetadata(ClassMetadata $metadata): bool
      */
     private function getPropertyTypes(string $className, string $property): TypeInfoType|array|null
     {
-        if (method_exists($this->typeExtractor, 'getType')) {
+        if (class_exists(TypeInfoType::class) && method_exists($this->typeExtractor, 'getType')) {
             return $this->typeExtractor->getType($className, $property);
         }