MAGETWO-70139: Fixed coding standard violations in the Framework\Interception namespace #9359

 - ClassReference test updated to support trait detection

Author: ishakhsuvarov

lib/internal/Magento/Framework/App/Utility/Files.php

@@ -1391,7 +1391,8 @@ private function classFileExistsCheckContent($fullPath, $namespace, $className)
             $fileContent = file_get_contents($fullPath);
             if (strpos($fileContent, 'namespace ' . $namespace) !== false
                 && (strpos($fileContent, 'class ' . $className) !== false
-                    || strpos($fileContent, 'interface ' . $className) !== false)
+                    || strpos($fileContent, 'interface ' . $className) !== false
+                    || strpos($fileContent, 'trait ' . $className) !== false)
             ) {
                 return true;
             }