Are you sure the factory works correctly?

``` js
class ThingFactory {

/*@ngInject*/
constructor($timeout) {
this.$timeout = $timeout;
}

newThing() {
console.log('Getting a new Thing...');
return this.$timeout(() => new Thing(), 100);
}
}

register('app').factory('thingFactory', ThingFactory);
```

In my app, `newThing()` doesn't have access to `ThingFactory` object's `this`. Rather `this` points to `window`.

Start with the ThingFactory example in the issue and inspect how AngularJS registers and invokes the factory, especially the newThing() call and its this binding. Reproduce the reported window binding, then verify that the factory method retains the expected object context and add or update a regression test if the repository provides a relevant test location.

Written by the indexing model from the issue text.