Animate position of a sublayer when animating a UIView.

AnimatedSublayer.swift

    public override func layoutSubviews() {
        super.layoutSubviews()

        // If the view is animating apply the animation to the sublayer
        CATransaction.begin()
        if let animation = layer.animationForKey("position") {
            CATransaction.setAnimationDuration(animation.duration)
            CATransaction.setAnimationTimingFunction(animation.timingFunction)
        } else {
            CATransaction.disableActions()
        }
        if mySubLayer.superlayer == layer {
            mySubLayer.frame = bounds
        }
        CATransaction.commit()
    }