Originally Posted by
MSPeconomist
Not a communal trough, but a trough inside a stall.
Unless I'm totally misunderstanding what you're describing, I haven't seen anything like that in Taiwan in 40 years (and I've lived here for 17 of those years). Not denying their existence (obviously, I haven't visited every restroom on the island), but for the purposes of this discussion, the odds of a tourist stumbling across one of these are next to zero.
I have seen them a lot in rural China, though.