bindings: Supports inheritance of [Unforgeable] attributes as accessor-type properties.

Source/bindings/scripts/code_generator_v8.py

Index: Source/bindings/scripts/code_generator_v8.py
diff --git a/Source/bindings/scripts/code_generator_v8.py b/Source/bindings/scripts/code_generator_v8.py
index 4169c23a2edca55f96e650d5aa4846aeb8229ea6..6d3a6c282faf4e81c714c8242afe6031912458bd 100644
--- a/Source/bindings/scripts/code_generator_v8.py
+++ b/Source/bindings/scripts/code_generator_v8.py
@@ -245,10 +245,9 @@ class CodeGeneratorV8(CodeGeneratorBase):
             header_template_filename = 'interface.h'
             cpp_template_filename = 'interface.cpp'
             interface_context = v8_interface.interface_context
-        header_template = self.jinja_env.get_template(header_template_filename)
-        cpp_template = self.jinja_env.get_template(cpp_template_filename)
 
         template_context = interface_context(interface)
+        includes.update(interface_info.get('cpp_includes', {}).get(component, set()))
         if not interface.is_partial and not is_testing_target(full_path):
             template_context['header_includes'].add(self.info_provider.include_path_for_export)
             template_context['exported'] = self.info_provider.specifier_for_export
@@ -257,6 +256,9 @@ class CodeGeneratorV8(CodeGeneratorBase):
             template_context['header_includes'].add('core/dom/DOMTypedArray.h')
         elif interface_info['include_path']:
             template_context['header_includes'].add(interface_info['include_path'])
+
+        header_template = self.jinja_env.get_template(header_template_filename)
+        cpp_template = self.jinja_env.get_template(cpp_template_filename)
         header_text, cpp_text = render_template(
             include_paths, header_template, cpp_template, template_context,
             component)