title: Ember event for best discarding changes between same Route
body: <p>I have an Ember list and an edit form.
  Each time the selected item of the list changes the edit form discards any changes and loads new model.</p>
  
  <p>My problem is that there is no way to discard changes because the deactivate event does NOT fire.</p>
  
  <p>For example going from <code>url/favs/123/edit</code> to <code>url/favs/456/edit</code> deactivate (and exit) event does NOT fire. So there is no way to properly discard any changes.</p>
  
  <p>Here is the part of my code I am referring to:</p>
  
  <pre class="lang-js prettyprint-override"><code>App.Router.map(function() {
      this.resource('favs', { path: '/favs' }, function() {
          this.route('new');
          this.route('edit', { path: ':fav_id/edit' })
      });
  });
  
  [...]
  
  App.FavsEditRoute = Ember.Route.extend({
      deactivate: function() {
          var model = this.get('currentModel');
          if(model &amp;&amp; model.get('isDirty')) {
              model.get('transaction').rollback();
          }
      },
  
      model: function(params) {
          return App.Fav.find(params.fav_id);
      },
  });
  </code></pre>