Make classes for union types exported.

Source/bindings/scripts/code_generator_v8.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 312 matching lines @@
         self.target_component = target_component
         set_global_type_info(info_provider)
 
     def generate_code(self):
         union_types = self.info_provider.union_types
         if not union_types:
             return ()
         header_template = self.jinja_env.get_template('union.h')
         cpp_template = self.jinja_env.get_template('union.cpp')
         template_context = v8_union.union_context(
-            union_types, self.info_provider.interfaces_info)
+            union_types, self.info_provider.interfaces_info, self.target_component)
         template_context['code_generator'] = module_pyname
         capitalized_component = self.target_component.capitalize()
         template_context['header_filename'] = 'bindings/%s/v8/UnionTypes%s.h' % (
             self.target_component, capitalized_component)
         template_context['macro_guard'] = 'UnionType%s_h' % capitalized_component
 
         # Add UnionTypesCore.h as a dependency when we generate modules union types
         # because we only generate union type containers which are used by both
         # core and modules in UnionTypesCore.h.
         # FIXME: This is an ad hoc workaround and we need a general way to
@@ skipping 94 matching lines @@
 
     # Create a dummy file as output for the build system,
     # since filenames of individual cache files are unpredictable and opaque
     # (they are hashes of the template path, which varies based on environment)
     with open(dummy_filename, 'w') as dummy_file:
         pass  # |open| creates or touches the file
 
 
 if __name__ == '__main__':
     sys.exit(main(sys.argv))