Explicitly mark first 2 args of addEventListener/removeEventListener as optional

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 53 matching lines @@
     is_call_with_script_state = has_extended_attribute_value(method, 'CallWith', 'ScriptState')
     if is_call_with_script_state:
         includes.add('bindings/v8/ScriptState.h')
     is_check_security_for_node = 'CheckSecurity' in extended_attributes
     if is_check_security_for_node:
         includes.add('bindings/v8/BindingSecurity.h')
     is_custom_element_callbacks = 'CustomElementCallbacks' in extended_attributes
     if is_custom_element_callbacks:
         includes.add('core/dom/custom/CustomElementCallbackDispatcher.h')
 
+    has_event_listener_argument = any(
+        argument for argument in arguments
+        if argument.idl_type.name == 'EventListener')
     is_check_security_for_frame = (
         'CheckSecurity' in interface.extended_attributes and
         'DoNotCheckSecurity' not in extended_attributes)
     is_raises_exception = 'RaisesException' in extended_attributes
 
     return {
         'activity_logging_world_list': v8_utilities.activity_logging_world_list(method),  # [ActivityLogging]
         'arguments': [generate_argument(interface, method, argument, index)
                       for index, argument in enumerate(arguments)],
         'conditional_string': v8_utilities.conditional_string(method),
         'cpp_type': idl_type.cpp_type,
         'cpp_value': this_cpp_value,
         'deprecate_as': v8_utilities.deprecate_as(method),  # [DeprecateAs]
         'do_not_check_signature': not(is_static or
             v8_utilities.has_extended_attribute(method,
                 ['DoNotCheckSecurity', 'DoNotCheckSignature', 'NotEnumerable',
                  'ReadOnly', 'RuntimeEnabled', 'Unforgeable'])),
         'function_template': function_template(),
         'idl_type': idl_type.base_type,
+        'has_event_listener_argument': has_event_listener_argument,
         'has_exception_state':
+            has_event_listener_argument or
             is_raises_exception or
             is_check_security_for_frame or
             any(argument for argument in arguments
                 if argument.idl_type.name == 'SerializedScriptValue' or
-                   argument.idl_type.is_integer_type) or
-            name in ['addEventListener', 'removeEventListener', 'dispatchEvent'],
+                   argument.idl_type.is_integer_type),
         'is_call_with_execution_context': has_extended_attribute_value(method, 'CallWith', 'ExecutionContext'),
         'is_call_with_script_arguments': is_call_with_script_arguments,
         'is_call_with_script_state': is_call_with_script_state,
         'is_check_security_for_frame': is_check_security_for_frame,
         'is_check_security_for_node': is_check_security_for_node,
         'is_custom': 'Custom' in extended_attributes,
         'is_custom_element_callbacks': is_custom_element_callbacks,
         'is_do_not_check_security': 'DoNotCheckSecurity' in extended_attributes,
         'is_do_not_check_signature': 'DoNotCheckSignature' in extended_attributes,
         'is_implemented_by': 'ImplementedBy' in extended_attributes,
@@ skipping 29 matching lines @@
     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
     use_heap_vector_type = is_variadic_wrapper_type and idl_type.is_will_be_garbage_collected
     return {
         'cpp_type': idl_type.cpp_type_args(will_be_in_heap_object=use_heap_vector_type),
         'cpp_value': this_cpp_value,
         'enum_validation_expression': idl_type.enum_validation_expression,
         'has_default': 'Default' in extended_attributes,
+        'has_event_listener_argument': any(
+            argument_so_far for argument_so_far in method.arguments[:index]
+            if argument_so_far.idl_type.name == 'EventListener'),
         'idl_type_object': idl_type,
         # Dictionary is special-cased, but arrays and sequences shouldn't be
         'idl_type': not idl_type.array_or_sequence_type and idl_type.base_type,
         'index': index,
         'is_clamp': 'Clamp' in extended_attributes,
         'is_callback_interface': idl_type.is_callback_interface,
         'is_nullable': idl_type.is_nullable,
         'is_optional': argument.is_optional,
         'is_strict_type_checking': 'StrictTypeChecking' in extended_attributes,
         'is_variadic_wrapper_type': is_variadic_wrapper_type,
@@ skipping 98 matching lines @@
 
 
 def union_arguments(idl_type):
     """Return list of ['result0Enabled', 'result0', 'result1Enabled', ...] for union types, for use in setting return value"""
     return [arg
             for i in range(len(idl_type.member_types))
             for arg in ['result%sEnabled' % i, 'result%s' % i]]
 
 IdlType.union_arguments = property(lambda self: None)
 IdlUnionType.union_arguments = property(union_arguments)