Fix an eta expansion bug in the grammar compiler

Eta expansion is applied between partial evaluation and PMCFG generation.
The buggy version generated type incorrect terms, but PMCFG generation
apparently worked anyway.

src/compiler/GF/Compile/GeneratePMCFG.hs

@@ -154,9 +154,7 @@ convert opts gr cenv loc term ty@(_,val) pargs =
             then-} normalForm cenv loc (expand ty term) -- new evaluator
             --else term -- old evaluator is invoked from GF.Compile.Optimize
 
-expand ty@(context,val) = recordExpand val . etaExpand ty
-
-etaExpand (context,val) = mkAbs pars . flip mkApp args
+expand (context,val) = mkAbs pars . recordExpand val . flip mkApp args
   where pars = [(Explicit,v) | v <- vars]
         args = map Vr vars
         vars = map (\(bt,x,t) -> x) context