Adding stack traces to error400 and error500 when debug > 0.

Adding the stack trace element.

cake/libs/error_handler.php

@@ -222,6 +222,7 @@ public function error400($error) {
 		$this->controller->set(array(
 			'name' => $message,
 			'url' => h($url),
+			'error' => $error,
 		));
 		$this->_outputMessage('error400');
 	}
@@ -238,6 +239,7 @@ public function error500($error) {
 		$this->controller->set(array(
 			'name' => __('An Internal Error Has Occurred'),
 			'message' => h($url),
+			'error' => $error,
 		));
 		$this->_outputMessage('error500');
 	}

cake/libs/view/elements/exception_stack_trace.ctp

@@ -0,0 +1,24 @@
+<?php
+/**
+ * Prints a stack trace for an exception
+ *
+ * PHP 5
+ *
+ * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
+ * Copyright 2005-2009, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ *
+ * Licensed under The MIT License
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright     Copyright 2005-2010, Cake Software Foundation, Inc. (http://cakefoundation.org)
+ * @link          http://cakephp.org CakePHP(tm) Project
+ * @package       cake
+ * @subpackage    cake.cake.libs.view.templates.elements
+ * @since         CakePHP(tm) v 1.3
+ * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
+ */
+?>
+<h4>Stack Trace</h4>
+<pre>
+<?php echo $error->getTraceAsString(); ?>
+</pre>

cake/libs/view/errors/error400.ctp

@@ -24,4 +24,9 @@
 		__('The requested address %s was not found on this server.'),
 		"<strong>'{$url}'</strong>"
 	); ?>
-</p>
+</p>
+<?php 
+if (Configure::read('debug') > 0 ):
+	echo $this->element('exception_stack_trace');
+endif;
+?>

cake/libs/view/errors/error500.ctp

@@ -22,3 +22,8 @@
 	<strong><?php echo __('Error', true); ?>: </strong>
 	<?php echo __('An Internal Error Has Occurred.'); ?>
 </p>
+<?php 
+if (Configure::read('debug') > 0 ):
+	echo $this->element('exception_stack_trace');
+endif;
+?>