Add network throttling as an enterprise policy

chrome/browser/chromeos/net/network_throttling_observer.h

Index: chrome/browser/chromeos/net/network_throttling_observer.h
diff --git a/chrome/browser/chromeos/net/network_throttling_observer.h b/chrome/browser/chromeos/net/network_throttling_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..744065766b39d24636f5634c0b3062ece04485e9
--- /dev/null
+++ b/chrome/browser/chromeos/net/network_throttling_observer.h
@@ -0,0 +1,42 @@
+// 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 CHROME_BROWSER_CHROMEOS_NET_NETWORK_THROTTLING_OBSERVER_H_
+#define CHROME_BROWSER_CHROMEOS_NET_NETWORK_THROTTLING_OBSERVER_H_
+
+#include <string>
+
+#include "base/memory/weak_ptr.h"

[Lei Zhang, 2016/10/29 16:04:04]

nit: not used

+#include "components/prefs/pref_change_registrar.h"
+
+class PrefRegistrySimple;
+class Profile;
+
+namespace chromeos {
+
+// NetworkThrottlingObserver is a singleton, owned by

[Lei Zhang, 2016/10/29 16:04:04]

Usually a singleton would not have a public constructor. Instead there's only a
public static Get() method that's backed by a base::LazyInstance, or
base::Singleton. *shrug*

+// ChromeBrowserMainPartsChromeos.
+// This class is responsible for propagating network bandwidth throttling policy
+// changes (prefs::kNetworkThrottlingEnabled) in Chrome down to Shill which
+// implements by calling 'tc' in the kernel.
+class NetworkThrottlingObserver {
+ public:
+  explicit NetworkThrottlingObserver(PrefService* local_state);
+  ~NetworkThrottlingObserver();
+
+  static void RegisterPrefs(PrefRegistrySimple* registry);
+
+ private:
+  // Callback used when prefs::kNetworkThrottlingEnabled changes
+  void OnPreferenceChanged(const std::string& pref_name);
+
+  PrefService* local_state_;
+  PrefChangeRegistrar pref_change_registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(NetworkThrottlingObserver);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_NET_NETWORK_THROTTLING_OBSERVER_H_