IDL: Generate union type containers

Source/modules/modules.gyp

 #
 # 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
@@ skipping 36 matching lines @@
     ],
     'defines': [
       'BLINK_IMPLEMENTATION=1',
       'INSIDE_BLINK',
     ],
     'sources': [
       '<@(modules_files)',
       '<@(bindings_modules_v8_files)',
       '<@(bindings_modules_v8_generated_aggregate_files)',
       '<@(bindings_modules_v8_generated_partial_aggregate_files)',
+      '<@(bindings_modules_v8_generated_union_type_files)',
       '<(bindings_modules_v8_output_dir)/initPartialInterfacesInModules.cpp',
     ],
     # Disable c4267 warnings until we fix size_t to int truncations.
     'msvs_disabled_warnings': [ 4267, 4334, ]
   },
   {
     # GN version: //third_party/WebKit/Source/modules:modules_testing
     'target_name': 'modules_testing',
     'type': 'static_library',
     'dependencies': [
       '../config.gyp:config',
       '../core/core.gyp:webcore',
     ],
     'defines': [
       'BLINK_IMPLEMENTATION=1',
       'INSIDE_BLINK',
     ],
     'sources': [
       '<@(modules_testing_files)',
       '<(bindings_modules_v8_output_dir)/V8InternalsPartial.cpp',
       '<(bindings_modules_v8_output_dir)/V8InternalsPartial.h',
     ],
 
   }],
 }