null check entity in filetree for orderByFoldersFirst

services/web/public/coffee/ide/file-tree/controllers/FileTreeController.coffee

@@ -31,7 +31,7 @@ define [
 			)
 
 		$scope.orderByFoldersFirst = (entity) ->
-			return '0' if entity.type == "folder"
+			return '0' if entity?.type == "folder"
 			return '1'
 
 		$scope.startRenamingSelected = () ->