How do I resolve an expected Ember.PromiseProxyMixin rejection?

I ran into this odd case when I was attempting to use the PromiseProxyMixin to clean up my templates. One of the situations was when I had a component that rendered a list after a search is completed with our API. The searching was debounced because it triggers when the search term changes. I then wrote a cancelation mechanism that would reject the last pending promise before making a new one this.set('promise', newPromise). I started noticing that these rejected promises were being spit out to our logging service because the Ember.onerror were trapping all unhandled rejections even though the Component I had expected that.

Normally in a promise chain you can avoid unhandled errors by making sure you place a .catch() at the end of the chain. However, I don't know how to do this if the promise is meant to be used in a PromiseProxyMixin.

Here is a JSBin that illustrates the problem with expected rejections in a PromiseProxyMixin.