New Twiddle

components.my-component.js

import Ember from 'ember';

const {get,set} = Ember;

export default Ember.Component.extend({
  init() {
    this._super(...arguments);
    const info = {};
    info.total = {};
    info['total']["2009"] = 9;
    set(this, 'info', info);
  },
  actions: {
    testDontWork() {
      var info = this.get("info");
      info['total']["2010"] = 10;
      this.rerender();
    },
    testDoesWork() {
      var info = this.get("info");
      set(info, 'total.2011', 11);
    },
    testNotifyChange() {
      var info = this.get("info");
      info['total']["2012"] = 12;
      this.notifyPropertyChange('info');
    }
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>

{{my-component}}

templates.components.my-component.hbs

<br>
<button onclick={{action "testDontWork"}}>testDontWork</button>
<button onclick={{action "testDoesWork"}}>testDoesWork</button>
<button onclick={{action "testNotifyChange"}}>testNotifyChange</button>

<br>
Totals:
<ul>
{{#each-in info.total as |k t|}}
  <li>{{t}}</li>
{{/each-in}}
</ul>
<br>

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1"
  }
}