Use a class for CodeGeneratorV8

Source/bindings/scripts/unstable/v8_callback_interface.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 21 matching lines @@
 This is a rewrite of the Perl IDL compiler in Python, but is not complete.
 Once it is complete, we will switch all IDL files over to Python at once.
 Until then, please work on the Perl IDL compiler.
 For details, see bug http://crbug.com/239771
 """
 
 from v8_globals import includes
 import v8_types
 import v8_utilities
 
-CALLBACK_INTERFACE_H_INCLUDES = set([
+CALLBACK_INTERFACE_H_INCLUDES = frozenset([
     'bindings/v8/ActiveDOMCallback.h',
     'bindings/v8/DOMWrapperWorld.h',
     'bindings/v8/ScopedPersistent.h',
 ])
-CALLBACK_INTERFACE_CPP_INCLUDES = set([
+CALLBACK_INTERFACE_CPP_INCLUDES = frozenset([
     'bindings/v8/V8Binding.h',
     'bindings/v8/V8Callback.h',
     'core/dom/ExecutionContext.h',
     'wtf/Assertions.h',
     'wtf/GetPtr.h',  # FIXME: remove if can eliminate WTF::getPtr
     'wtf/RefPtr.h',
 ])
 
 
 def cpp_to_v8_conversion(idl_type, name):
@@ skipping 24 matching lines @@
     includes.clear()
     includes.update(CALLBACK_INTERFACE_CPP_INCLUDES)
     name = callback_interface.name
 
     methods = [generate_method(operation)
                for operation in callback_interface.operations]
     template_contents = {
         'conditional_string': v8_utilities.conditional_string(callback_interface),
         'cpp_class': name,
         'v8_class': v8_utilities.v8_class_name(callback_interface),
-        'header_includes': CALLBACK_INTERFACE_H_INCLUDES,
+        'header_includes': set(CALLBACK_INTERFACE_H_INCLUDES),
         'methods': methods,
     }
     return template_contents
 
 
 def add_includes_for_operation(operation):
     v8_types.add_includes_for_type(operation.idl_type)
     for argument in operation.arguments:
         v8_types.add_includes_for_type(argument.idl_type)
 
@@ skipping 29 matching lines @@
     argument_declarations = [
             '%s %s' % (cpp_type(argument.idl_type), argument.name)
             for argument in arguments]
     if call_with_this_handle:
         argument_declarations.insert(0, 'ScriptValue thisValue')
     return  {
         'argument_declarations': argument_declarations,
         'arguments': [generate_argument(argument) for argument in arguments],
         'handles': ['%sHandle' % argument.name for argument in arguments],
     }