[I accidentally left this out of the previous commit.]
Throwing didn't handle a container owned by the hero which contained
items owned by the shopkeeper. I'm still not quite sure what's going on
there, but throwing the container out of the shop didn't give any feedback
but did add to shop charges which don't show up in ``I x'' (but do get
revealed by ``$'' or ``I $''). Now there's some shop feedback for the
throw and the contents show up for ``I x''.