Fixed an issue when finding return values that are immediately scruitinized

When changing 'immediateCaseOnReturn' so that it returned blocks, rather
than labels to blocks, I accidentaly modified 'nonTailReturns' so that it
didn't output the block that control would return to after a function
--- it instead returned the block making the call.  This lead to us
finding no functions which have a case statement and return from a
function call.