t.debounce('_distribute', host._distributeContent));
}
},
appendChild: function (node) {
return this.insertBefore(node);
},
insertBefore: function (node, ref_node) {
if (ref_node && TreeApi.Logical.getParentNode(ref_node) !== this.node) {
throw Error('The ref_node to be inserted before is not a child ' + 'of this node');
}
if (node.nodeType !== Node.DOCUMENT_FRAGMENT_NODE) {
var parent = TreeApi.Logical.getParentNode(node);
if (parent) {
if (DomApi.hasApi(parent)) {
dom(parent).notifyObserver();
}
this._rem