public void back() {
    resetPageIsLoading();
    runSynchronously(new Runnable() {
      public void run() {
        webview.goBack();
      }
    }, 500);
    waitForPageToLoad();
  }
Unconventional way of adding a Javascript interface but the main reason why I took this way
is that it is working stable compared to the webview.addJavascriptInterface way.
selendroid-server/src/main/java/io/selendroid/server/model/SelendroidWebDriver.java