added a DebuClassLoader::findFile() method to make the wrapping less invasive

src/Symfony/Component/ClassLoader/DebugClassLoader.php

@@ -69,6 +69,18 @@ class DebugClassLoader
         spl_autoload_unregister(array($this, 'loadClass'));
     }
 
+    /**
+     * Finds a file by class name
+     *
+     * @param string $class A class name to resolve to file
+     *
+     * @return string|null
+     */
+    public function findFile($class)
+    {
+        return $this->classFinder->findFile($class);
+    }
+
     /**
      * Loads the given class or interface.
      *