Yes it is, at least as of five days ago. It's somewhat inconvenient though. To get from your room at the HC to the laundry room at the HH, you have to make four elevator trips: room to HC lobby, HC lobby to ground, exit HC and walk around to HH, ground to HH lobby, HH lobby to laundry room one floor up. You also have to obtain a laundry room key from the HH front desk, and they asked me to return it each time I left the HH property, i.e., when my clothes were in the washer and dryer, and I went back to the lounge at the HC.
I'd be annoyed to do this more than once during a stay, though I guess you could cut out a lot of the to-and-fro by just hanging out at the lobby of the HH while your clothes are in the washer and dryer (it's pleasant enough, but I wanted my free welcome drinks at the HC
).