We apply an AncestorClippingLayer whenever the ancestor's clip is non infinite. This is wasteful in the not-uncommon situation where the child is entirely contained within the clip.

We should use logic similar to AncestorClippingMaskLayers to not create the layer when the child is entirely in.

Note the logic is not identical; we still need a clip layer if the child is entirely outside the clip, while we do not need a mask in that case.