@Override
  public void setAlpha(int alpha) {
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.R) {
      int color = getColor();
      setColor((clamp(alpha, 0, 255) << 24) | (color & 0xFFFFFF));
    } else {
      super.setAlpha(clamp(alpha, 0, 255));
    }
  }
Overrides {@link android.graphics.Paint#setAlpha(int)} to avoid
unnecessary {@link android.graphics.ColorSpace.Named ColorSpace$Named[] }
allocations when calling this method in Android 29 or lower.

@param alpha set the alpha component [0..255] of the paint's color.
lottie/src/main/java/com/airbnb/lottie/animation/LPaint.java