Introducing gpu::CommandBufferId as a distinct, IdType<...>-based type.

gpu/ipc/id_type_traits.h

+// Copyright 2016 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 GPU_IPC_ID_TYPE_TRAITS_H_
+#define GPU_IPC_ID_TYPE_TRAITS_H_
+
+#include <string>
+
+#include "base/pickle.h"
+#include "gpu/command_buffer/common/id_type.h"
+#include "ipc/ipc_message_utils.h"
+#include "ipc/ipc_param_traits.h"
+
+namespace IPC {
+
+template <typename TypeMarker, typename WrappedType, WrappedType kInvalidValue>
+struct ParamTraits<gpu::IdType<TypeMarker, WrappedType, kInvalidValue>> {
+  using param_type = gpu::IdType<TypeMarker, WrappedType, kInvalidValue>;
+  static void GetSize(base::PickleSizer* sizer, const param_type& p) {
+    GetParamSize(sizer, p.GetUnsafeValue());
+  }
+  static void Write(base::Pickle* m, const param_type& p) {
+    WriteParam(m, p.GetUnsafeValue());
+  }
+  static bool Read(const base::Pickle* m,
+                   base::PickleIterator* iter,
+                   param_type* r) {
+    WrappedType value;
+    if (!ReadParam(m, iter, &value))
+      return false;
+    *r = param_type::FromUnsafeValue(value);
+    return true;
+  }
+  static void Log(const param_type& p, std::string* l) {
+    LogParam(p.GetUnsafeValue(), l);
+  }
+};
+
+}  // namespace IPC
+
+#endif  // GPU_IPC_ID_TYPE_TRAITS_H_