[econstr] Continue consolidation of EConstr API under `interp`.

This commit was motivated by true spurious conversions arising in my
`to_constr` debug branch.

The changes here need careful review as the tradeoffs are subtle and
still a lot of clean up remains to be done in `vernac/*`.

We have opted for penalize [minimally] the few users coming from true
`Constr`-land, but I am sure we can tweak code in a much better way.

In particular, it is not clear if internalization should take an
`evar_map` even in the cases where it is not triggered, see the
changes under `plugins` for a good example.

Also, the new return type of `Pretyping.understand` should undergo
careful review.

We don't touch `Impargs` as it is not clear how to proceed, however,
the current type of `compute_implicits_gen` looks very suspicious as
it is called often with free evars.

Some TODOs are:

- impargs was calling whd_all, the Econstr equivalent can be either
  + Reductionops.whd_all [which does refolding and no sharing]
  + Reductionops.clos_whd_flags with all as a flag.

1 files changed, 2 insertions, 2 deletions

diff --git a/vernac/record.ml b/vernac/record.ml
index 1140e3d37..44113bfad 100644
--- a/vernac/record.ml
+++ b/vernac/record.ml
@@ -70,7 +70,7 @@ let interp_fields_evars env sigma impls_env nots l =
       let impls =
 	match i with
 	| Anonymous -> impls
-        | Name id -> Id.Map.add id (compute_internalization_data env Constrintern.Method (EConstr.to_constr sigma t') impl) impls
+        | Name id -> Id.Map.add id (compute_internalization_data env sigma Constrintern.Method t' impl) impls
       in
       let d = match b' with
 	      | None -> LocalAssum (i,t')
@@ -145,7 +145,7 @@ let typecheck_params_and_fields finite def id poly pl t ps nots fs =
   let assums = List.filter is_local_assum newps in
   let params = List.map (RelDecl.get_name %> Name.get_id) assums in
   let ty = Inductive (params,(finite != Declarations.BiFinite)) in
-  let impls_env = compute_internalization_env env0 ~impls:impls_env ty [id] [EConstr.to_constr sigma arity] [imps] in
+  let impls_env = compute_internalization_env env0 sigma ~impls:impls_env ty [id] [arity] [imps] in
   let env2,sigma,impls,newfs,data =
     interp_fields_evars env_ar sigma impls_env nots (binders_of_decls fs)
   in