Given a #PangoAttrList and callback function, removes any elements of @list for which @func returns %TRUE and inserts them into a new list.
callback function; returns %TRUE if an attribute should be filtered out.
Data to be passed to @func
Return: the new #PangoAttrList or %NULL if no attributes of the given types were found.
1.2
See Implementation
Given a #PangoAttrList and callback function, removes any elements of @list for which @func returns %TRUE and inserts them into a new list.