Simon Peyton Jones authored Feb 26, 2017 and David Feuer committed Feb 26, 2017

This is just a local refactoring.

I originally planned to try floating top-level bindings inwards,
but I backed off from that leaving only this (harmless) refactoring,
which has no behavioural effect.

I also make FloatIn into a ModGuts -> ModGuts function; again not
necessary now, but no harm either.

My attempt also used the new function CoreFVs.freeVarsBind; but
that too is a plausible refactorig of freeVars, so I left it in too.

Reviewers: austin, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D3180