Remove deadcode, fixes #4345, fixes #4268

src/Composer/Repository/CompositeRepository.php

@@ -108,20 +108,6 @@ class CompositeRepository implements RepositoryInterface
         return $matches ? call_user_func_array('array_merge', $matches) : array();
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public function filterPackages($callback, $class = 'Composer\Package\Package')
-    {
-        foreach ($this->repositories as $repository) {
-            if (false === $repository->filterPackages($callback, $class)) {
-                return false;
-            }
-        }
-
-        return true;
-    }
-
     /**
      * {@inheritdoc}
      */