memory-infra: Introduce mojo interfaces and service stubs

services/memory_infra/public/cpp/memory_infra_traits.h

+// Copyright 2017 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 SERVICES_MEMORY_INFRA_PUBLIC_CPP_MEMORY_INFRA_TRAITS_H_
+#define SERVICES_MEMORY_INFRA_PUBLIC_CPP_MEMORY_INFRA_TRAITS_H_
+
+#include "base/trace_event/memory_dump_request_args.h"
+#include "services/memory_infra/public/interfaces/memory_infra.mojom.h"
+
+namespace mojo {
+
+template<>
+struct EnumTraits<memory_infra::mojom::DumpType,
+                  base::trace_event::MemoryDumpType> {
+  static memory_infra::mojom::DumpType ToMojom(
+      base::trace_event::MemoryDumpType type);
+  static bool FromMojom(memory_infra::mojom::DumpType input,
+                        base::trace_event::MemoryDumpType* out);
+};
+
+template<>
+struct EnumTraits<memory_infra::mojom::LevelOfDetail,
+                  base::trace_event::MemoryDumpLevelOfDetail> {
+  static memory_infra::mojom::LevelOfDetail ToMojom(
+      base::trace_event::MemoryDumpLevelOfDetail level_of_detail);
+  static bool FromMojom(memory_infra::mojom::LevelOfDetail input,
+                        base::trace_event::MemoryDumpLevelOfDetail* out);
+};
+
+template<>
+struct StructTraits<memory_infra::mojom::RequestArgsDataView,
+                    base::trace_event::MemoryDumpRequestArgs> {
+  static uint64_t dump_guid(
+      const base::trace_event::MemoryDumpRequestArgs& args) {
+    return args.dump_guid;
+  }
+  static memory_infra::mojom::DumpType dump_type(

[Ken Rockot(use gerrit already), 2017/01/17 19:34:53]

This implementation (and level_of_detail below) is redundant. You can just
return the non-mojom enum type here without any explicit cast or conversion. The
EnumTraits will be used automatically.

[chiniforooshan1, 2017/01/17 21:26:23]

Done.

+      const base::trace_event::MemoryDumpRequestArgs& args);
+  static memory_infra::mojom::LevelOfDetail level_of_detail(
+      const base::trace_event::MemoryDumpRequestArgs& args);
+  static bool Read(memory_infra::mojom::RequestArgsDataView input,
+                   base::trace_event::MemoryDumpRequestArgs* out);
+};
+
+}  // namespace mojo
+
+#endif  // SERVICES_MEMORY_INFRA_PUBLIC_CPP_MEMORY_INFRA_TRAITS_H_