Adds some error checking for launching a dialog - the tree node must resolve a tree alias - this is why the new 'options' are not working.

src/Umbraco.Web.UI.Client/src/common/services/navigation.service.js

@@ -581,6 +581,10 @@ angular.module('umbraco.services')
                 var treeAlias = treeService.getTreeAlias(args.node);
                 var packageTreeFolder = treeService.getTreePackageFolder(treeAlias);
 
+                if (!treeAlias) {
+                    throw "Could not get tree alias for node " + args.node.id;
+                }
+
                 if (packageTreeFolder) {
                     templateUrl = Umbraco.Sys.ServerVariables.umbracoSettings.appPluginsPath + 
                         "/" + packageTreeFolder +