docs: public static int multiplyColorAlpha(int color, int alpha) {
      if (alpha == 255) {
        return color;
      }
      if (alpha == 0) {
        return color & 0x00FFFFFF;
      }
      alpha = alpha + (alpha >> 7); // make it 0..256
      int colorAlpha = color >>> 24;
      int multipliedAlpha = colorAlpha * alpha >> 8;
      return (multipliedAlpha << 24) | (color & 0x00FFFFFF);
    }