when the user changes the HTML, the ember metamorphs get wiped out.

I ran into this issue:

https://github.com/emberjs/ember.js/issues/1582

When using a element, ember creates metamorphs to track the changes to the model and update the view. 

However, those metamorphs get removed by the browser when the user updates the HTML via contenteditable .

But since we're updating the view on our own anyway, we don't really need the metamorphs.
By overriding the render method,  we skip the metamoprhs, and they're never missed.