Action bubbling from components

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  layout: Ember.computed.alias('contentTemplate'),
});

controllers.application.js

import Ember from 'ember';
import hbs from 'htmlbars-inline-precompile'; 

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  result: '',
  myContentTemplate: hbs('<button class="btn" {{action "testAction"}}>Click me</button>'),
  actions: {
    testAction() {
      this.set('result', 'TestAction called.');
    }
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<p>
{{my-component contentTemplate=myContentTemplate}}
<h1>{{result}}</h1>
</p>
<p>Using ember 2.8.0 this works, using "release" (currently 2.8.2) the component logs an error.</p>
<div class="alert alert-danger"><pre>VM188 ember.debug.js:6778 Uncaught Error: Assertion Failed: &lt;twiddle@component:my-component::ember355&gt; had no action handler for: testAction</pre></div>
<br>
<br>
{{outlet}}
<br>
<br>

twiddle.json

{
  "version": "0.10.5",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "release",
    "ember-data": "2.8.0",
    "ember-template-compiler": "release",
    "ember-testing": "release",
    "ember-cli-htmlbars-inline-precompile": "^0.3.5"
  },
  "addons": {}
}