[Re-land] Add network throttling as enterprise policy

chrome/browser/chromeos/net/network_throttling_observer.cc

+// 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.
+
+#include "chrome/browser/chromeos/net/network_throttling_observer.h"
+
+#include <memory>
+#include <string>
+
+#include "base/macros.h"
+#include "base/memory/ptr_util.h"
+#include "base/sys_info.h"
+#include "base/values.h"
+#include "chrome/common/pref_names.h"
+#include "chromeos/network/network_state_handler.h"
+#include "components/prefs/pref_member.h"
+#include "components/prefs/pref_registry_simple.h"
+#include "components/prefs/pref_service.h"
+
+namespace chromeos {
+
+NetworkThrottlingObserver::NetworkThrottlingObserver(PrefService* local_state)
+    : local_state_(local_state) {
+  pref_change_registrar_.Init(local_state_);
+
+  base::Callback<void(const std::string&)> throttle_callback = base::Bind(
+      &NetworkThrottlingObserver::OnPreferenceChanged, base::Unretained(this));
+
+  pref_change_registrar_.Add(prefs::kNetworkThrottlingEnabled,
+                             throttle_callback);
+}
+
+NetworkThrottlingObserver::~NetworkThrottlingObserver() {}
+
+void NetworkThrottlingObserver::RegisterPrefs(PrefRegistrySimple* registry) {
+  registry->RegisterDictionaryPref(prefs::kNetworkThrottlingEnabled);
+}
+
+void NetworkThrottlingObserver::OnPreferenceChanged(
+    const std::string& pref_name) {
+  DCHECK(pref_name == prefs::kNetworkThrottlingEnabled);
+
+  const base::DictionaryValue* throttling_policy =
+      local_state_->GetDictionary(prefs::kNetworkThrottlingEnabled);
+
+  // Default is to disable throttling if the policy is not found.
+  bool enabled = false;
+  uint32_t upload_rate = 0, download_rate = 0;
+  if (throttling_policy) {
+    int upload_rate_read = 0;
+    int download_rate_read = 0;
+
+    throttling_policy->GetBoolean("enabled", &enabled);
+
+    if (throttling_policy->GetInteger("upload_rate_kbits", &upload_rate_read) &&
+        upload_rate_read > 0) {
+      upload_rate = upload_rate_read;
+    }
+
+    if (throttling_policy->GetInteger("download_rate_kbits",
+                                      &download_rate_read) &&
+        download_rate_read > 0) {
+      download_rate = download_rate_read;
+    }
+  }
+  NetworkHandler::Get()->network_state_handler()->SetNetworkThrottlingStatus(
+      enabled, upload_rate, download_rate);
+}
+
+}  // namespace chromeos