[gimp/gimp-2-10] app: relax precondition checks in gimp_operation_config_get_type()

[Michael Natterer <mitch src gnome org>]

commit c743aed29d9de8048058624b5a358ec7aa0d7d70
Author: Michael Natterer <mitch gimp org>
Date:   Fri Jul 13 13:55:24 2018 +0200

    app: relax precondition checks in gimp_operation_config_get_type()
    
    Only require the parent type if the requested type is not already
    registered.
    
    (cherry picked from commit 9ef39b507b652b8ed65c9a018666d75a6ffa8c00)

 app/operations/gimp-operation-config.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/app/operations/gimp-operation-config.c b/app/operations/gimp-operation-config.c
index 904bc3dcc3..88ff32e90e 100644
--- a/app/operations/gimp-operation-config.c
+++ b/app/operations/gimp-operation-config.c
@@ -271,7 +271,6 @@ gimp_operation_config_get_type (Gimp        *gimp,
 
   g_return_val_if_fail (GIMP_IS_GIMP (gimp), G_TYPE_NONE);
   g_return_val_if_fail (operation != NULL, G_TYPE_NONE);
-  g_return_val_if_fail (g_type_is_a (parent_type, GIMP_TYPE_OBJECT), G_TYPE_NONE);
 
   config_types = gimp_operation_config_get_type_table (gimp);
 
@@ -281,6 +280,9 @@ gimp_operation_config_get_type (Gimp        *gimp,
     {
       GTypeQuery query;
 
+      g_return_val_if_fail (g_type_is_a (parent_type, GIMP_TYPE_OBJECT),
+                            G_TYPE_NONE);
+
       g_type_query (parent_type, &query);
 
       {