javascript detect div height change, DOMSubtreeModified may help

In one of my project, it is implemented by "one page". Any request is an ajax call and the javascript refreshes the div when it gets data returned from ajax.
The div is using NiceScroll for scroll bar. The "resize" method of NiceScroll shall be triggered when the height of div is changed.
Now the javascript need detect the div height changing. I am using "DOMSubtreeModified".