Remove a TODO from the code comments that is complete
Remove a TODO from the code comments that is complete

WithUser... helpers do support non-snapshot rootfs now.

Signed-off-by: Phil Estes <dbac1f450dc8326caa7ba104b384a0eca642250c@linux.vnet.ibm.com>

mikebrow/containerd,dmcgowan/containerd,mikebrow/containerd,thaJeztah/containerd,thaJeztah/containerd,containerd/containerd,containerd/containerd,crosbymichael/containerd,miaoyq/containerd,crosbymichael/containerd,estesp/containerd,vdemeester/containerd,dmcgowan/containerd,vdemeester/containerd,estesp/containerd,miaoyq/containerd