code: function typeWeight(treeElement)
      {
          var type = treeElement.type();
          if (type === WebInspector.NavigatorTreeOutline.Types.Domain) {
              if (treeElement.titleText === WebInspector.targetManager.inspectedPageDomain())
                  return 1;
              return 2;
          }
          if (type === WebInspector.NavigatorTreeOutline.Types.FileSystem)
              return 3;
          if (type === WebInspector.NavigatorTreeOutline.Types.Folder)
              return 4;
          return 5;
      }
docs: Insert in the alphabetical order, first domains, then folders, then scripts.