Move the call to chill out of assuming; instead, convert sum to Sum.
Move the call to chill out of assuming; instead, convert sum to Sum.

This causes `simplify' to either go into an infinite loop, or to try to simplify
an absurd number of expressions of the form `RootOf(size(_Z))', which takes an
effectively infinite length of time (I haven't waited long enough to find out
which).

This reverts baea3e32c601dc88cd9abe8a40f73b01d0005bad.

zachsully/hakaru,zachsully/hakaru