docs: private void ensureOrCancelAnimator(FloatingActionButton fab) {
          if (mFabTranslationYAnimator == null) {
              mFabTranslationYAnimator = ViewCompat.animate(fab);
              mFabTranslationYAnimator.setDuration(400);
              mFabTranslationYAnimator.setInterpolator(FAST_OUT_SLOW_IN_INTERPOLATOR);
          } else {
              mFabTranslationYAnimator.cancel();
          }
      }