Ext.data.TreeStore#setRootNode doesn't accept Model instance

[PHaroZ]

In Ext 4.0.6

According to API doc setRootNode should accept an Ext.data.Model instance, but it seem to be bogus. My instance is always wrapped again in a new Model instance.

My override :

Ext.override(Ext.data.TreeStore, {
            setRootNode : function(root) {
                var me = this;

                root = root || {};
                if (!root.isModel) { // instead of root.isNode
                    Ext.applyIf(root, {
                                id : me.defaultRootId,
                                text : 'Root',
                                allowDrag : false
                            });
                    root = Ext.ModelManager.create(root, me.model);
                }
                Ext.data.NodeInterface.decorate(root);

                me.getProxy().getReader().buildExtractors(true);

                me.tree.setRootNode(root);

                if (!root.isLoaded() && (me.autoLoad === true || root.isExpanded())) {
                    me.load({
                                node : root
                            });
                }

                return root;
            }
        });

I think this is that ext team wanted to write.