Fix security component causing black holes on error pages.

Fixes #2966

lib/Cake/Controller/Component/SecurityComponent.php

@@ -205,6 +205,10 @@ class SecurityComponent extends Component {
  * @return void
  */
 	public function startup(Controller $controller) {
+		if ($controller->name == 'CakeError') {
+			return true;
+		}
+
 		$this->request = $controller->request;
 		$this->_action = $this->request->params['action'];
 		$this->_methodsRequired($controller);