Mojo C++ bindings: add support for UnionTraits.

mojo/public/tools/bindings/generators/cpp_templates/module.h.tmpl

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 {%- if variant -%}
 {%-   set variant_path = "%s-%s"|format(module.path, variant) -%}
 {%- else -%}
 {%-   set variant_path = module.path -%}
 {%- endif -%}
 
@@ skipping 59 matching lines @@
 #include "mojo/public/cpp/bindings/map.h"
 #include "mojo/public/cpp/bindings/map_data_view.h"
 #include "mojo/public/cpp/bindings/message_filter.h"
 #include "mojo/public/cpp/bindings/native_enum.h"
 #include "mojo/public/cpp/bindings/native_struct.h"
 #include "mojo/public/cpp/bindings/native_struct_data_view.h"
 #include "mojo/public/cpp/bindings/no_interface.h"
 #include "mojo/public/cpp/bindings/string_data_view.h"
 #include "mojo/public/cpp/bindings/struct_ptr.h"
 #include "mojo/public/cpp/bindings/struct_traits.h"
+#include "mojo/public/cpp/bindings/union_traits.h"
 #include "{{variant_path}}-internal.h"
 {%- for import in imports %}
 {%-   if variant %}
 #include "{{"%s-%s.h"|format(import.module.path, variant)}}"
 {%-   else %}
 #include "{{import.module.path}}.h"
 {%-   endif %}
 {%- endfor %}
 {%- if not for_blink %}
 #include "mojo/public/cpp/bindings/array.h"
@@ skipping 176 matching lines @@
 
 {{namespace_end()}}
 {{data_view_traits(struct)}}
 {{namespace_begin()}}
 
 {%    endif %}
 {%- endfor %}
 
 {%- for union in unions %}
 {%    include "wrapper_union_class_template_definition.tmpl" %}
+{%    include "union_data_view_definition.tmpl" %}
 {%- endfor %}
 
 {%- for struct in structs %}
 {%-   if not struct|is_native_only_kind %}
 {%      include "wrapper_class_template_definition.tmpl" %}
 {%      include "struct_data_view_definition.tmpl" %}
 {%-   endif %}
 
 {%-   if struct.enums %}
 {{namespace_end()}}
@@ skipping 54 matching lines @@
 {#--- Union Serialization Helpers -#}
 {%  if unions %}
 {%-   for union in unions %}
 {%      include "union_serialization_declaration.tmpl" %}
 {%-   endfor %}
 {%- endif %}
 
 }  // namespace mojo
 
 #endif  // {{header_guard}}