@MainThread
  public void resumeAnimation() {
    running = true;
    postFrameCallback();
    lastFrameTimeNs = 0;
    if (isReversed() && getFrame() == getMinFrame()) {
      setFrame(getMaxFrame());
    } else if (!isReversed() && getFrame() == getMaxFrame()) {
      setFrame(getMinFrame());
    }
    notifyResume();
  }
Returns the current speed. This will be affected by repeat mode REVERSE.
lottie/src/main/java/com/airbnb/lottie/utils/LottieValueAnimator.java