FBTF: Move individual XXXMsg_Params structs to a new file.

ipc/ipc_param_traits.h

+// Copyright (c) 2010 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.
+
+#ifndef IPC_IPC_PARAM_TRAITS_H_
+#define IPC_IPC_PARAM_TRAITS_H_
+#pragma once
+
+// Our IPC system uses the following partially specialized header to define how
+// a data type is read, written and logged in the IPC system.
+
+namespace IPC {
+
+template <class P> struct ParamTraits {
+};
+
+template <class P>
+struct SimilarTypeTraits {
+  typedef P Type;
+};
+
+}  // namespace IPC
+
+#endif  // IPC_IPC_PARAM_TRAITS_H_