What do you mean by "self contained unit"?

If you mean to ask if the toilet and the shower are in the same room, then yes -- they share the same lockable room. If you mean to ask if the shower is in a self contained unit within the bathroom, then not really. They might have a small divider, i don't recall exactly.

IIRC many of the rooms include a toilet and a shower. Some of them only include a toilet. The signs outside the rooms make it clear.