please include function randomLineWithColor.

static void varyLineWithColor(LineWithColor l, int w, int h) {
  int i = random(randomLineWithColor_minLineWidth < randomLineWithColor_maxLineWidth ? 4 : 3);
  if (i == 0) l.a = varyPoint(l.a, w, h);
  else if (i == 1) l.b = varyPoint(l.b, w, h);
  else if (i == 2) l.color = varyColor(l.color);
  else {
    l.width = varyIntInRange(l.width,
      randomLineWithColor_minLineWidth, randomLineWithColor_maxLineWidth);
    limitLineThickness(l, randomLineWithColor_maxThickness, randomLineWithColor_minLineWidth);
  }
}

Began life as a copy of #1014954