code: @Override
      public void onActivityResult(int requestCode, int resultCode, Intent data) {
          super.onActivityResult(requestCode, resultCode, data);
          sessionTracker.getSession().onActivityResult(this.getActivity(), requestCode, resultCode, data);
      }
docs: Called when the activity that was launched exits. This method manages session
  information when a session is opened. If this method is overridden in subclasses,
  be sure to call {@code super.onActivityResult(...)} first.