rustc_metadata: Do not forget to encode inherent impls for foreign types

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -1753,6 +1753,7 @@ impl EncodeContext<'a, 'tcx> {
         self.encode_const_stability(def_id);
         self.encode_deprecation(def_id);
         self.encode_item_type(def_id);
+        self.encode_inherent_implementations(def_id);
         if let hir::ForeignItemKind::Fn(..) = nitem.kind {
             record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
             self.encode_variances_of(def_id);