Let me first put the disclaimer up here that the existence of this post by no means indicates that there is actually a memory leak, but I wanted to get some experts's opinions.
From what I am seeing, repeated (polling) calls to findAll are resulting in a leak. The leak is small in the example because the dataset being returned by the fixture is small.
When applying my minor league skills at using Chrome's Dev Tools I see a bunch of stuff related to madeMap and teardownMap when looking heap snapshots.
I let the example run for the last 7 hours. Over that time the heap snapshot has grown from 4MB to 103MB, but he amount of JavaScript memory used as displayed in Chrome's Task Manager has remained steady at around 13000K (7000K live). Not sure what that indicated.
Here's a screenshot: