Make Base.getTypeBasedMethod stop considering meta type as prefix.

Use of meta types is deprecated. Ignoring them makes it possible to optimize
getTypeBasedMethod thanks to portal types as classes.

product/ERP5Type/Base.py

@@ -2961,16 +2961,14 @@ class Base( CopyContainer,
     try:
       script = type_base_cache[cache_key]
     except KeyError:
-      class_name_list = [portal_type, self.getMetaType()] + \
-        [base_class.__name__ for base_class in self.__class__.mro()
-                             if issubclass(base_class, Base)]
       script_name_end = '_' + method_id
-      for script_name_begin in class_name_list:
-        script_id = script_name_begin.replace(' ','') + script_name_end
-        script = getattr(self, script_id, None)
-        if script is not None:
-          type_base_cache[cache_key] = aq_inner(script)
-          return script
+      for base_class in self.__class__.mro():
+        if issubclass(base_class, Base):
+          script_id = base_class.__name__.replace(' ','') + script_name_end
+          script = getattr(self, script_id, None)
+          if script is not None:
+            type_base_cache[cache_key] = aq_inner(script)
+            return script
       type_base_cache[cache_key] = None
 
     if script is not None: