user text-change event fired after calling updateContents(delta)

[benbro]

[Describe the issue]
quill.updateContents(delta) should fire one text-change event with 'api' source but a text-change event with 'user' source is also fired.
It might be related to this commit:
e5651c6

Steps for Reproduction

1. Visit http://beta.quilljs.com/
2. Paste this in the console:

quill.on('text-change', function(delta, oldDelta, source) {
  console.log(source + ': ', JSON.stringify(delta.ops));
});
var ops = [{"insert":"a"},{"insert":"\n","attributes":{"list":"ordered"}}];
quill.setContents(ops);
var delta = [{"retain":2},{"insert":"\n","attributes":{"list":"ordered"}}];
quill.updateContents(delta);
JSON.stringify(quill.getContents().ops);

Expected behavior: [expected]
Only 'api' text-change event with insert in the delta.
Actual behavior: [actual]
We are getting a 'user' text-change event with insert in the delta.
The 'api' text-change event has a delta with retain and no insert:

// user source
[{"retain":2},{"insert":"\n"}]
// api source
[{"retain":2},{"retain":1,"attributes":{"list":"ordered"}}]

Platforms:
Firefox 47 on Windows 7

Version:
1.0.0-beta.6