Remove the default Component callbacks.

This will help make the callbacks more efficient, and reduce the number
of no-op callbacks  It also means that there is no need to call parent
anymore when simply extending Component.

lib/Cake/Controller/Component.php

@@ -29,12 +29,24 @@
  * Components can provide several callbacks that are fired at various stages of the request
  * cycle. The available callbacks are:
  *
- * - `initialize()` - Fired before the controller's beforeFilter method.
- * - `startup()` - Fired after the controller's beforeFilter method.
- * - `beforeRender()` - Fired before the view + layout are rendered.
- * - `shutdown()` - Fired after the action is complete and the view has been rendered.
+ * - `initialize()` - Called before the controller's beforeFilter method.
+ * - `startup()` - Called after the controller's beforeFilter method,
+ *   and before the controller action is called.
+ * - `beforeRender()` - Called before the Controller beforeRender, and
+ *   before the view class is loaded.
+ * - `shutdown()` - Called after the action is complete and the view has been rendered.
  *    but before Controller::afterFilter().
- * - `beforeRedirect()` - Fired before a redirect() is done.
+ * - `beforeRedirect()` - Called before Controller::redirect(), and
+ *   before a redirect() is done. Allows you to replace the URL that will
+ *   be redirected to with a new URL. The return of this method can either be an
+ *   array or a string. If the return is an array and contains a 'url' key.
+ *   You may also supply the following:
+ *
+ *   - `status` The status code for the redirect
+ *   - `exit` Whether or not the redirect should exit.
+ *
+ *   If your response is a string or an array that does not contain a 'url' key it will
+ *   be used as the new URL to redirect to.
  *
  * Each callback has a slightly different signature:
  *
@@ -109,74 +121,6 @@ public function __get($name) {
 		}
 	}
 
-/**
- * Called before the Controller::beforeFilter().
- *
- * @param Event $event An Event instance
- * @param Controller $controller Controller with components to initialize
- * @return void
- * @link http://book.cakephp.org/2.0/en/controllers/components.html#Component::initialize
- */
-	public function initialize(Event $event, Controller $controller) {
-	}
-
-/**
- * Called after the Controller::beforeFilter() and before the controller action
- *
- * @param Event $event An Event instance
- * @param Controller $controller Controller with components to startup
- * @return void
- * @link http://book.cakephp.org/2.0/en/controllers/components.html#Component::startup
- */
-	public function startup(Event $event, Controller $controller) {
-	}
-
-/**
- * Called before the Controller::beforeRender(), and before
- * the view class is loaded, and before Controller::render()
- *
- * @param Event $event An Event instance
- * @param Controller $controller Controller with components to beforeRender
- * @return void
- * @link http://book.cakephp.org/2.0/en/controllers/components.html#Component::beforeRender
- */
-	public function beforeRender(Event $event, Controller $controller) {
-	}
-
-/**
- * Called after Controller::render() and before the output is printed to the browser.
- *
- * @param Event $event An Event instance
- * @param Controller $controller Controller with components to shutdown
- * @return void
- * @link http://book.cakephp.org/2.0/en/controllers/components.html#Component::shutdown
- */
-	public function shutdown(Event $event, Controller $controller) {
-	}
-
-/**
- * Called before Controller::redirect(). Allows you to replace the URL that will
- * be redirected to with a new URL. The return of this method can either be an array or a string.
- *
- * If the return is an array and contains a 'url' key. You may also supply the following:
- *
- * - `status` The status code for the redirect
- * - `exit` Whether or not the redirect should exit.
- *
- * If your response is a string or an array that does not contain a 'url' key it will
- * be used as the new URL to redirect to.
- *
- * @param Event $event An Event instance
- * @param Controller $controller Controller with components to beforeRedirect
- * @param string|array $url Either the string or URL array that is being redirected to.
- * @param integer $status The status code of the redirect
- * @param boolean $exit Will the script exit.
- * @return array|void Either an array or null.
- * @link http://book.cakephp.org/2.0/en/controllers/components.html#Component::beforeRedirect
- */
-	public function beforeRedirect(Event $event, Controller $controller, $url, $status = null, $exit = true) {
-	}
-
 /**
  * Get the Controller callbacks this Component is interested in.
  *