Fix CRITICAL GIMP warnings when calling GEGL operations

Author: kamilburda

wrappers/pypdb.py

@@ -100,7 +100,7 @@ def _get_proc_by_name(self, proc_name, proc_class):
 
   @staticmethod
   def _gimp_pdb_procedure_exists(proc_name):
-    return Gimp.get_pdb().procedure_exists(proc_name)
+    return Gimp.is_canonical_identifier(proc_name) and Gimp.get_pdb().procedure_exists(proc_name)
 
   @staticmethod
   def _gegl_operation_exists(proc_name):
@@ -394,7 +394,6 @@ def __call__(self, *args, **kwargs):
     drawable_filter.set_blend_mode(blend_mode)
     drawable_filter.set_opacity(opacity)
     drawable_filter.set_visible(visible)
-    drawable_filter.update()
 
     config = drawable_filter.get_config()
 
@@ -425,6 +424,8 @@ def __call__(self, *args, **kwargs):
 
       config.set_property(arg_name, processed_value)
 
+    drawable_filter.update()
+
     if merge_filter:
       drawable.merge_filter(drawable_filter)