js/libs/ember-1.5.1.js
function(views, start, removed, added) {
    if (added > 0) {
      var changedViews = views.slice(start, start+added);
      this.initializeViews(changedViews, this, get(this, 'templateData'));
      this.currentState.childViewsDidChange(this, views, start, added);
    }
    this.propertyDidChange('childViews');
  }
function(views, start, removed, added) {
    if (added > 0) {
      var changedViews = views.slice(start, start+added);
      this.initializeViews(changedViews, this, get(this, 'templateData'));
      this.currentState.childViewsDidChange(this, views, start, added);
    }
    this.propertyDidChange('childViews');
  }
When a child view is added, make sure the DOM gets updated appropriately.

If the view has already rendered an element, we tell the child view to
create an element and insert it into the DOM. If the enclosing container
view has already written to a buffer, but not yet converted that buffer
into an element, we insert the string representation of the child into the
appropriate place in the buffer.

@private
@method childViewsDidChange
@param {Ember.Array} views the array of child views afte the mutation has occurred
@param {Number} start the start position of the mutation
@param {Number} removed the number of child views removed
@param {Number} the number of child views added