ColorWithColor = function (color1, color2, length, index)
{
    if (length === undefined) { length = 100; }
    if (index === undefined) { index = 0; }

    return RGBWithRGB(color1.r, color1.g, color1.b, color2.r, color2.g, color2.b, length, index);
}
Interpolates between the two given color objects over the length supplied.

@function Phaser.Display.Color.Interpolate.ColorWithColor
@memberof Phaser.Display.Color.Interpolate
@static
@since 3.0.0

@param {Phaser.Display.Color} color1 - The first Color object.
@param {Phaser.Display.Color} color2 - The second Color object.
@param {number} [length=100] - Distance to interpolate over.
@param {number} [index=0] - Index to start from.

@return {Phaser.Types.Display.ColorObject} An object containing the interpolated color values.