Disallow certain blocking DOM calls during microtask execution.

third_party/WebKit/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 161 matching lines @@
         'is_variadic': arguments and arguments[-1].is_variadic,
         'measure_as': v8_utilities.measure_as(method, interface),  # [MeasureAs]
         'name': name,
         'number_of_arguments': len(arguments),
         'number_of_required_arguments': len([
             argument for argument in arguments
             if not (argument.is_optional or argument.is_variadic)]),
         'number_of_required_or_variadic_arguments': len([
             argument for argument in arguments
             if not argument.is_optional]),
+        'not_during_microtasks': 'NotDuringMicrotasks' in extended_attributes,
         'on_instance': v8_utilities.on_instance(interface, method),
         'on_interface': v8_utilities.on_interface(interface, method),
         'on_prototype': v8_utilities.on_prototype(interface, method),
         'only_exposed_to_private_script': is_only_exposed_to_private_script,
         'origin_trial_enabled_function': v8_utilities.origin_trial_enabled_function_name(method, interface),  # [OriginTrialEnabled]
         'private_script_v8_value_to_local_cpp_value': idl_type.v8_value_to_local_cpp_value(
             extended_attributes, 'v8Value', 'cppValue', isolate='scriptState->isolate()', bailout_return_value='false'),
         'property_attributes': property_attributes(interface, method),
         'returns_promise': method.returns_promise,
         'runtime_enabled_function': v8_utilities.runtime_enabled_function_name(method),  # [RuntimeEnabled]
@@ skipping 265 matching lines @@
     return method.idl_type and method.idl_type.name == 'Promise'
 
 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))