Introduce ES6 iterator for DOM objects.

Source/bindings/scripts/v8_interface.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 # coding=utf-8
 #
 # 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
@@ skipping 85 matching lines @@
     is_active_dom_object = 'ActiveDOMObject' in extended_attributes
 
     # [CheckSecurity]
     is_check_security = 'CheckSecurity' in extended_attributes
     if is_check_security:
         includes.add('bindings/core/v8/BindingSecurity.h')
 
     # [DependentLifetime]
     is_dependent_lifetime = 'DependentLifetime' in extended_attributes
 
+    # [Iterable]
+    iterator_method = None
+    if 'Iterable' in extended_attributes:
+        iterator_operation = IdlOperation(interface.idl_name)
+        iterator_operation.name = 'iterator'
+        iterator_operation.idl_type = IdlType('Iterator')
+        iterator_operation.extended_attributes['RaisesException'] = None
+        iterator_operation.extended_attributes['CallWith'] = 'ScriptState'
+        iterator_method = v8_methods.method_context(interface,
+                                                    iterator_operation)
+
     # [MeasureAs]
     is_measure_as = 'MeasureAs' in extended_attributes
     if is_measure_as:
         includes.add('core/frame/UseCounter.h')
 
     # [SetWrapperReferenceFrom]
     reachable_node_function = extended_attributes.get('SetWrapperReferenceFrom')
     if reachable_node_function:
         includes.update(['bindings/core/v8/V8GCController.h',
                          'core/dom/Element.h'])
@@ skipping 49 matching lines @@
         'interface_name': interface.name,
         'is_active_dom_object': is_active_dom_object,
         'is_audio_buffer': is_audio_buffer,
         'is_check_security': is_check_security,
         'is_dependent_lifetime': is_dependent_lifetime,
         'is_document': is_document,
         'is_event_target': inherits_interface(interface.name, 'EventTarget'),
         'is_exception': interface.is_exception,
         'is_node': inherits_interface(interface.name, 'Node'),
         'is_script_wrappable': is_script_wrappable,
+        'iterator_method': iterator_method,
         'lifetime': 'Dependent'
             if (has_visit_dom_wrapper or
                 is_active_dom_object or
                 is_dependent_lifetime)
             else 'Independent',
         'measure_as': v8_utilities.measure_as(interface),  # [MeasureAs]
         'parent_interface': parent_interface,
         'pass_cpp_type': cpp_template_type(
             cpp_ptr_type('PassRefPtr', 'RawPtr', this_gc_type),
             cpp_name(interface)),
@@ skipping 949 matching lines @@
         deleter = next(
             method
             for method in interface.operations
             if ('deleter' in method.specials and
                 len(method.arguments) == 1 and
                 str(method.arguments[0].idl_type) == 'DOMString'))
     except StopIteration:
         return None
 
     return property_deleter(deleter)