src: Clean up. (#31261)

* src: Clean up.

* wip

src/core/Object3D.js

@@ -47,7 +47,7 @@ const _removedEvent = { type: 'removed' };
 const _childaddedEvent = { type: 'childadded', child: null };
 
 /**
- * Fires when a new child object has been added.
+ * Fires when a child object has been removed.
  *
  * @event Object3D#childremoved
  * @type {Object}