IDL: Add [LegacyInterfaceTypeChecking] extended attribute

Source/bindings/scripts/v8_methods.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 21 matching lines @@
 Extends IdlTypeBase and IdlUnionType with property |union_arguments|.
 
 Design doc: http://www.chromium.org/developers/design-documents/idl-compiler
 """
 
 from idl_definitions import IdlArgument, IdlOperation
 from idl_types import IdlTypeBase, IdlUnionType, inherits_interface
 from v8_globals import includes
 import v8_types
 import v8_utilities
-from v8_utilities import has_extended_attribute_value, is_unforgeable
+from v8_utilities import (has_extended_attribute_value, is_unforgeable,
+                          is_legacy_interface_type_checking)
 
 
 # Methods with any of these require custom method registration code in the
 # interface's configure*Template() function.
 CUSTOM_REGISTRATION_EXTENDED_ATTRIBUTES = frozenset([
     'DoNotCheckSecurity',
     'DoNotCheckSignature',
     'NotEnumerable',
     'Unforgeable',
 ])
@@ skipping 136 matching lines @@
         'world_suffixes': ['', 'ForMainWorld'] if 'PerWorldBindings' in extended_attributes else [''],  # [PerWorldBindings],
     }
 
 
 def argument_context(interface, method, argument, index):
     extended_attributes = argument.extended_attributes
     idl_type = argument.idl_type
     this_cpp_value = cpp_value(interface, method, index)
     is_variadic_wrapper_type = argument.is_variadic and idl_type.is_wrapper_type
 
-    type_checking_interface = (
-        (has_extended_attribute_value(interface, 'TypeChecking', 'Interface') or
-         has_extended_attribute_value(method, 'TypeChecking', 'Interface')) and
+    # [TypeChecking=Interface] / [LegacyInterfaceTypeChecking]
+    has_type_checking_interface = (
+        not is_legacy_interface_type_checking(interface, method) and
         idl_type.is_wrapper_type)
 
     if ('ImplementedInPrivateScript' in extended_attributes and
         not idl_type.is_wrapper_type and
         not idl_type.is_basic_type):
         raise Exception('Private scripts supports only primitive types and DOM wrappers.')
 
     set_default_value = argument.set_default_value
     this_cpp_type = idl_type.cpp_type_args(extended_attributes=extended_attributes,
                                            raw_type=True,
                                            used_as_variadic_argument=argument.is_variadic)
     return {
         'cpp_type': (
             v8_types.cpp_template_type('Nullable', this_cpp_type)
             if idl_type.is_explicit_nullable and not argument.is_variadic
             else this_cpp_type),
         'cpp_value': this_cpp_value,
         # FIXME: check that the default value's type is compatible with the argument's
         'set_default_value': set_default_value,
         'enum_validation_expression': idl_type.enum_validation_expression,
         'handle': '%sHandle' % argument.name,
         # FIXME: remove once [Default] removed and just use argument.default_value
         'has_default': 'Default' in extended_attributes or set_default_value,
-        'has_type_checking_interface': type_checking_interface,
+        'has_type_checking_interface': has_type_checking_interface,
         # Dictionary is special-cased, but arrays and sequences shouldn't be
         'idl_type': idl_type.base_type,
         'idl_type_object': idl_type,
         'index': index,
         'is_callback_function': idl_type.is_callback_function,
         'is_callback_interface': idl_type.is_callback_interface,
         # FIXME: Remove generic 'Dictionary' special-casing
         'is_dictionary': idl_type.is_dictionary or idl_type.base_type == 'Dictionary',
         'is_explicit_nullable': idl_type.is_explicit_nullable,
         'is_nullable': idl_type.is_nullable,
@@ skipping 211 matching lines @@
 
 IdlOperation.returns_promise = property(method_returns_promise)
 
 
 def argument_conversion_needs_exception_state(method, argument):
     idl_type = argument.idl_type
     return (idl_type.v8_conversion_needs_exception_state or
             argument.is_variadic or
             (method.returns_promise and (idl_type.is_string_type or
                                          idl_type.is_enum)))