Fix V8 bindings for named constructors to set prototype object correctly

third_party/WebKit/Source/bindings/templates/attributes.cpp.tmpl

 {% from 'utilities.cpp.tmpl' import declare_enum_validation_variable, v8_value_to_local_cpp_value %}
 
 {##############################################################################}
 {% macro attribute_getter(attribute, world_suffix) %}
 static void {{attribute.name}}AttributeGetter{{world_suffix}}(
 {%- if attribute.is_data_type_property %}
 const v8::PropertyCallbackInfo<v8::Value>& info
 {%- else %}
 const v8::FunctionCallbackInfo<v8::Value>& info
 {%- endif %}) {
@@ skipping 405 matching lines @@
   {{cpp_class_or_partial}}V8Internal::{{attribute.name}}AttributeSetter{{world_suffix}}(v8Value, info);
   {% endif %}
 }
 {% endmacro %}
 
 
 {##############################################################################}
 {% macro attribute_configuration(attribute) %}
 {% from 'utilities.cpp.tmpl' import property_location %}
 {% if attribute.constructor_type %}
-{% set getter_callback =
-       '%sV8Internal::%sConstructorGetterCallback' % (cpp_class_or_partial, attribute.name)
-       if attribute.needs_constructor_getter_callback else
-       'v8ConstructorAttributeGetter' %}
+  {% if attribute.needs_constructor_getter_callback %}
+    {% set getter_callback =
+           '%sV8Internal::%sConstructorGetterCallback' % (cpp_class_or_partial, attribute.name) %}
+  {% else %}
+    {% set getter_callback =
+           'V8%s::NamedConstructorAttributeGetter' % (attribute.constructor_type)
+           if attribute.is_named_constructor else 'v8ConstructorAttributeGetter' %}
+  {% endif %}
 {% set setter_callback = '0' %}
 {% else %}{# regular attributes #}
 {% set getter_callback = '%sV8Internal::%sAttributeGetterCallback' %
            (cpp_class_or_partial, attribute.name) %}
 {% set setter_callback = '%sV8Internal::%sAttributeSetterCallback' %
            (cpp_class_or_partial, attribute.name)
        if attribute.has_setter else '0' %}
 {% endif %}
 {% set getter_callback_for_main_world =
        '%sForMainWorld' % getter_callback
        if attribute.is_per_world_bindings else '0' %}
 {% set setter_callback_for_main_world =
        '%sForMainWorld' % setter_callback
        if attribute.is_per_world_bindings and attribute.has_setter else '0' %}
 {% set wrapper_type_info =
        'const_cast<WrapperTypeInfo*>(&V8%s::wrapperTypeInfo)' %
            attribute.constructor_type
-       if attribute.constructor_type else '0' %}
+       if attribute.constructor_type and not attribute.is_named_constructor else '0' %}
 {% set property_attribute = 'static_cast<v8::PropertyAttribute>(%s)' %
                             ' | '.join(attribute.property_attributes) %}
 {% set cached_accessor_callback =
        '%sV8Internal::%sCachedAccessorCallback' % (cpp_class_or_partial, attribute.name)
        if attribute.is_cached_accessor else
        'nullptr' %}
 {% set holder_check = 'V8DOMConfiguration::DoNotCheckHolder'
        if attribute.is_lenient_this else 'V8DOMConfiguration::CheckHolder' %}
 {% set attribute_configuration_list = [
        '"%s"' % attribute.name,
        getter_callback,
        setter_callback,
        getter_callback_for_main_world,
        setter_callback_for_main_world,
        cached_accessor_callback,
        wrapper_type_info,
        property_attribute,
        property_location(attribute),
        holder_check,
    ] %}
 {{'{'}}{{attribute_configuration_list | join(', ')}}{{'}'}}
 {%- endmacro %}