docs: @Override
    public void start() {
      if (mIsRunning || mAnimationBackend == null || mAnimationBackend.getFrameCount() <= 1) {
        return;
      }
      mIsRunning = true;
      mStartTimeMs = now();
      mExpectedRenderTimeMs = mStartTimeMs;
      mLastFrameAnimationTimeMs = -1;
      mLastDrawnFrameNumber = -1;
      invalidateSelf();
      mAnimationListener.onAnimationStart(this);
    }