UnityEditor.TreeViewTest.TestDragging.DoDrag C# (CSharp) Method

            public override DragAndDropVisualMode DoDrag(TreeViewItem parentItem, TreeViewItem targetItem, bool perform, TreeViewDragging.DropPosition dropPos)
            {
                FooDragData genericData = DragAndDrop.GetGenericData("FooDragging") as FooDragData;
                TreeViewTest.FooTreeViewItem item = targetItem as TreeViewTest.FooTreeViewItem;
                TreeViewTest.FooTreeViewItem item2 = parentItem as TreeViewTest.FooTreeViewItem;
                if ((item2 == null) || (genericData == null))
                {
                    return DragAndDropVisualMode.None;
                }
                bool flag = this.ValidDrag(parentItem, genericData.m_DraggedItems);
                if (perform && flag)
                {
                    if (<>f__am$cache1 == null)
                    {
                        <>f__am$cache1 = x => x is TreeViewTest.FooTreeViewItem;