Fix issue where extension_loaded stopped constructor being recognised

src/Psalm/Internal/Analyzer/Statements/Expression/Call/NewAnalyzer.php

@@ -288,7 +288,6 @@ class NewAnalyzer extends \Psalm\Internal\Analyzer\Statements\Expression\CallAna
             $stmt->inferredType = new Type\Union([new TNamedObject($fq_class_name)]);
 
             if (strtolower($fq_class_name) !== 'stdclass' &&
-                $context->check_classes &&
                 $codebase->classlikes->classExists($fq_class_name)
             ) {
                 $storage = $codebase->classlike_storage_provider->get($fq_class_name);

tests/UnusedCodeTest.php

@@ -387,6 +387,16 @@ class UnusedCodeTest extends TestCase
 
                 (new D)->bar();'
             ],
+            'usedClassAfterExtensionLoaded' => [
+                '<?php
+                    class A {
+                        public function __construct() {}
+                    }
+
+                    if (extension_loaded("fdsfdsfd")) {
+                        new A();
+                    }',
+            ],
         ];
     }