Never clone List objects

Author: thiemowmde

src/GroupableCollection.js

@@ -15,7 +15,7 @@ var SELF = wb.datamodel.GroupableCollection = function WbDataModelGroupableColle
 
 $.extend( SELF.prototype, {
 	/**
-	 * Returns a copy of the collection items as list.
+	 * Returns the collection items as list.
 	 * @abstract
 	 *
 	 * @return {*[]}

src/List.js

@@ -71,7 +71,7 @@ var SELF = wb.datamodel.List = util.inherit(
 	 * @inheritdoc
 	 */
 	toArray: function() {
-		return this._items.slice();
+		return this._items;
 	},
 
 	/**