docs: public static void safeLoadStylesheets(String[] stylesheets, JavaScriptObject callback) {
  
          CmsStylesheetLoader loader = new CmsStylesheetLoader(Arrays.asList(stylesheets), new Runnable() {
  
              public native void call(JavaScriptObject jsCallback) /*-{
          jsCallback();
      }-*/;
  
              public void run() {
  
                  if (callback != null) {
                      call(callback);
                  }
              }
  
          });
          loader.loadWithTimeout(5000);
      }