Fixing refactor error.

Weirdly this does not trigger during testing.
PHP scope magic?

lib/grammar.php

@@ -40,7 +40,7 @@ class EvaluationContext {
  }
  $key = 'REMOTE_USER';
  if (array_key_exists($key, $_SERVER)) {
- return $_SERVER[$key] == $elmInstance->getStringValue();
+ return $_SERVER[$key] == $user;
  }
  return false;
  }