Convert utility process extension Unpacker IPC to mojo

extensions/common/manifest_location_param_traits.cc

Index: extensions/common/manifest_location_param_traits.cc
diff --git a/extensions/common/manifest_location_param_traits.cc b/extensions/common/manifest_location_param_traits.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ece9d3607fbc7e4784289a058bb84e4e678bb4ee
--- /dev/null
+++ b/extensions/common/manifest_location_param_traits.cc
@@ -0,0 +1,26 @@
+// Copyright (c) 2017 The Chromium Authors. All rights reserved.

[Devlin, 2017/03/09 15:52:11]

nit: no (c)

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extensions/common/manifest_location_param_traits.h"
+
+// Auto-generate IPC::ParamTraits<> code specializations for
+// sending and receiving enum extensions::Manifest::Location
+// over IPC.
+
+namespace IPC {
+
+#undef EXTENSIONS_COMMON_MANIFEST_LOCATION_PARAM_TRAITS_H_

[Devlin, 2017/03/09 15:52:11]

what does all this do?  Why do we repeat it 4x?

+#include "extensions/common/manifest_location_param_traits.h"
+#include "ipc/param_traits_size_macros.h"
+#undef EXTENSIONS_COMMON_MANIFEST_LOCATION_PARAM_TRAITS_H_
+#include "extensions/common/manifest_location_param_traits.h"
+#include "ipc/param_traits_write_macros.h"
+#undef EXTENSIONS_COMMON_MANIFEST_LOCATION_PARAM_TRAITS_H_
+#include "extensions/common/manifest_location_param_traits.h"
+#include "ipc/param_traits_read_macros.h"
+#undef EXTENSIONS_COMMON_MANIFEST_LOCATION_PARAM_TRAITS_H_
+#include "extensions/common/manifest_location_param_traits.h"
+#include "ipc/param_traits_log_macros.h"
+
+}  // namespace IPC