widl: If possible, use the interface name as prefix for the expr eval functions.

tools/widl/typegen.c

@@ -4727,7 +4727,7 @@ int write_expr_eval_routines(FILE *file, const char *iface)
         result = 1;
 
         print_file(file, 0, "static void __RPC_USER %s_%sExprEval_%04u(PMIDL_STUB_MESSAGE pStubMsg)\n",
-                   iface, name, callback_offset);
+                   eval->iface ? eval->iface->name : iface, name, callback_offset);
         print_file(file, 0, "{\n");
         if (type_get_type( eval->cont_type ) == TYPE_FUNCTION)
         {
@@ -4763,7 +4763,8 @@ void write_expr_eval_routine_list(FILE *file, const char *iface)
 
     LIST_FOR_EACH_ENTRY_SAFE(eval, cursor, &expr_eval_routines, struct expr_eval_routine, entry)
     {
-        print_file(file, 1, "%s_%sExprEval_%04u,\n", iface, eval->name, callback_offset);
+        print_file(file, 1, "%s_%sExprEval_%04u,\n",
+                   eval->iface ? eval->iface->name : iface, eval->name, callback_offset);
         callback_offset++;
         list_remove(&eval->entry);
         free(eval->name);