title: Ember checkbox click, change event not firing, gives error
body: <p>I have problem during use of checkbox in ember. I have used one boolean property for checked binding. Now i want to fire a event on change of this property or click on checkbox, but when i clicks it doesn't fires any of the event. Even it doesn't calls observer function on change of that property. below is the my code snippet,</p>
  
  <p>in View- observer on  "setAsRecurringAction" checked property or this can be a click event handler.</p>
  
  <pre><code>setActionSchedule: function() {
      if (this.get('setAsRecurringAction')) {
          $(".response-container").css({height: '38em'});
      } else {
          $(".response-container").css({height: '19em'});
      }
  }.observes('setAsRecurringAction')
  </code></pre>
  
  <p>template-</p>
  
  <pre><code>{{view Ember.Checkbox 
       checkedBinding="setAsRecurringAction"
       class="set-recurring"}}
  </code></pre>
  
  <p>and same code with action helper also didn't work,</p>
  
  <pre><code>{{view Ember.Checkbox 
      checkedBinding="setAsRecurringAction"
      class="set-recurring"
      action="setActionSchedule"}}
  </code></pre>
  
  <ul>
  <li>Some more info when i checks the checkbox throws error like "Uncaught TypeError: Cannot call method 'find' of undefined"</li>
  </ul>
  
  <p>thnx in advance.</p>