bindings: Moves custom getters/setters to the prototype chain.

Source/bindings/scripts/v8_utilities.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 450 matching lines @@
             member.is_static or
             is_unforgeable(interface, member) or
             'OverrideBuiltins' in interface.extended_attributes):
         return False
 
     # TODO(yukishiino): We should handle [Global] and [PrimaryGlobal] instead of
     # Window.
     if (interface.name == 'Window'):
         return member.idl_type.name == 'EventHandler'
 
-    # TODO(yukishiino): We should move all of the following members to prototype
-    # chains.
-    if 'Custom' in member.extended_attributes:
-        return False
-
     if 'ExposeJSAccessors' in interface.extended_attributes:
         return True
     if 'DoNotExposeJSAccessors' in interface.extended_attributes:
         return False
 
     return True
 
 
 # static, const
 def on_interface(interface, member):
@@ skipping 103 matching lines @@
     except StopIteration:
         return None
 
 
 IdlInterface.indexed_property_getter = property(indexed_property_getter)
 IdlInterface.indexed_property_setter = property(indexed_property_setter)
 IdlInterface.indexed_property_deleter = property(indexed_property_deleter)
 IdlInterface.named_property_getter = property(named_property_getter)
 IdlInterface.named_property_setter = property(named_property_setter)
 IdlInterface.named_property_deleter = property(named_property_deleter)