code: function(opt_randFunc) {
      var randFunc = opt_randFunc || randInt;
      var strong = randFunc(3);
      var color = 0xFF;
      for (var ii = 0; ii < 3; ++ii) {
        color = (color << 8) | (randFunc(128) + (ii === strong ? 128 : 64));
      }
      return color;
    }
docs: get a random 32bit color
  @param {function(number): number?) opt_randFunc function to generate random numbers
  @return {string} random 32bit color
  @memberOf module:Misc