Revert "Merge pull request #784 from ceeram/habtmmerge"

This reverts commit fa5aa6278f8a6df688462581fd8e0373ac4cbd54, reversing
changes made to 88604ac757198dbb2db55bd69e91060904c7b442.

lib/Cake/Model/Model.php

@@ -1755,7 +1755,7 @@ class Model extends Object implements CakeEventListener {
 				$this->getEventManager()->dispatch($event);
 			}
 			if (!empty($this->data)) {
-				$success = array_merge($success, $this->data);
+				$success = Hash::merge($success, $this->data);
 			}
 			$this->data = false;
 			$this->_clearCache();

lib/Cake/Test/Case/Model/ModelWriteTest.php

@@ -1170,7 +1170,6 @@ class ModelWriteTest extends BaseModelTest {
 		$this->assertFalse(empty($result));
 		$result = $TestModel->save();
 		$this->assertFalse(empty($result));
-		$this->assertEquals($data['Tag'], $result['Tag']);
 
 		$TestModel->unbindModel(array('belongsTo' => array('User'), 'hasMany' => array('Comment')));
 		$result = $TestModel->find('first', array('fields' => array('id', 'user_id', 'title', 'body'), 'conditions' => array('Article.id' => 2)));