code: function setAll(red, green, blue, brightness) {
    validateRGB(red, green, blue);
    validateBrightness(brightness, true);
  
    for (var i = 0; i < NUM_PIXELS; i++) {
      setPixelInternal(i, red, green, blue, brightness);
    }
  }
docs: Sets the specified RGB values, and optionally <code>brightness</code>, of all pixels.
  
  If you don't supply a <code>brightness</code> value, the last value set for each pixel be kept.
  
  @param {number} red - the amount of red to be set (between 0 and 255 - inclusive)
  @param {number} green - the amount of green to be set (between 0 and 255 - inclusive)
  @param {number} blue - the amount of blue to be set (between 0 and 255 - inclusive)
  @param {number} [brightness] - the brightness to be set (between 0 and 1 - inclusive)
  @return {void}
  @throws {RangeError} If <code>brightness</code> is less than 0 or greater than 1 or any color is less than 0 or
  greater than 255.
  @throws {TypeError} If any color is <code>null</code> or not a number, or <code>brightness</code> is not a number.
  @public