[Chromoting] Retrieve process resource usage (ProcessStats) and its tests

remoting/host/current_process_stats_agent.cc

+// 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.
+
+#include "remoting/host/current_process_stats_agent.h"
+
+namespace remoting {
+
+CurrentProcessStatsAgent::CurrentProcessStatsAgent(
+    const std::string& process_name)
+    : process_name_(process_name),
+      metrics_(base::ProcessMetrics::CreateCurrentProcessMetrics()) {}
+
+CurrentProcessStatsAgent::~CurrentProcessStatsAgent() = default;
+
+protocol::ProcessResourceUsage CurrentProcessStatsAgent::GetResourceUsage() {
+  protocol::ProcessResourceUsage current;
+  current.set_process_name(process_name_);
+  current.set_processor_usage(metrics_->GetPlatformIndependentCPUUsage());
+  current.set_working_set_size(metrics_->GetWorkingSetSize());
+  current.set_pagefile_size(metrics_->GetPagefileUsage());
+  return current;
+}
+
+}  // namespace remoting