bug #35557 [Config] dont catch instances of Error (nicolas-grekas)

This PR was merged into the 3.4 branch.

Discussion
----------

[Config] dont catch instances of Error

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix #35445, fix #35256
| License       | MIT
| Doc PR        | -

Commits
-------

e94c3fb87d [Config] dont catch instances of Error

src/Symfony/Component/Config/Resource/ClassExistenceResource.php

@@ -92,6 +92,8 @@ class ClassExistenceResource implements SelfCheckingResourceInterface, \Serializ
                 }
             } catch (\Throwable $e) {
                 $exists[1] = $e->getMessage();
+
+                throw $e;
             } finally {
                 self::$autoloadedClass = $autoloadedClass;
                 if (!--self::$autoloadLevel) {

src/Symfony/Component/Config/Tests/Fixtures/ParseError.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\Config\Tests\Fixtures;
+
+class ParseError
+{
+// missing closing bracket

src/Symfony/Component/Config/Tests/Resource/ClassExistenceResourceTest.php

@@ -15,6 +15,7 @@ use PHPUnit\Framework\TestCase;
 use Symfony\Component\Config\Resource\ClassExistenceResource;
 use Symfony\Component\Config\Tests\Fixtures\BadFileName;
 use Symfony\Component\Config\Tests\Fixtures\BadParent;
+use Symfony\Component\Config\Tests\Fixtures\ParseError;
 use Symfony\Component\Config\Tests\Fixtures\Resource\ConditionalClass;
 
 class ClassExistenceResourceTest extends TestCase
@@ -115,4 +116,15 @@ EOF
 
         $this->assertFalse($res->isFresh(0));
     }
+
+    /**
+     * @requires PHP 7
+     */
+    public function testParseError()
+    {
+        $this->expectException('ParseError');
+
+        $res = new ClassExistenceResource(ParseError::class, false);
+        $res->isFresh(0);
+    }
 }