rocqide when encoding is set to "LOCALE" always convert

UTF8 when converted to some locale may produce valid UTF8 but invalid
Coq (ie some unicode character may become \uXXXX)

Fix rocq-prover#11526

Author: SkySkimmer

ide/rocqide/ideutils.ml

@@ -219,10 +219,10 @@ let do_convert s =
     Glib.Convert.convert s ~to_codeset:"UTF-8" ~from_codeset:enc
   in
   let s =
-    if Glib.Utf8.validate s then (Minilib.log "Input is UTF-8"; s)
-    else match encoding#get with
-      |Preferences.Eutf8 | Preferences.Elocale -> from_loc ()
-      |Emanual enc -> try from_manual enc with _ -> from_loc ()
+    match encoding#get with
+    | Eutf8 when Glib.Utf8.validate s -> (Minilib.log "Input is UTF-8"; s)
+    | Eutf8 | Elocale -> from_loc ()
+    | Emanual enc -> try from_manual enc with _ -> from_loc ()
   in
   Utf8_convert.f s