cakephp/cakephp — pull request #3590 by Haititi (2014-05-28 16:26:52+00:00)
Title: 2.6 fix save() with habtm returning error

bug found while handling PR 3516.
https://github.com/cakephp/cakephp/pull/3516

$Model->save($data) may return false if the given $data to save does not contain some $Model related data.