emberjs/ember.js — pull request #1522 by ppcano (2012-11-06 18:24:04+00:00)
Title: Avoid didInsertElement event to be fired twice when inserting a view in the didInsertElement event of a ContainerView

Whenever a ContainerView inserted a view in its didInsertElement event, the child view was notified twice of its didInsertElement event.

Invoking firstly the childViews, the event will be triggered only to existing childViews and the new view will be notified via the _ensureChildrenAreInDOM method call.