Blimp Settings framework on the c++ side

blimp/client/core/settings/settings_observer.h

Index: blimp/client/core/settings/settings_observer.h
diff --git a/blimp/client/core/settings/settings_observer.h b/blimp/client/core/settings/settings_observer.h
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index 0000000000000000000000000000000000000000..6b1b7c2a026ea355d3b961cc96a2b4a54d17c9e9
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+++ b/blimp/client/core/settings/settings_observer.h
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+// 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 BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_OBSERVER_H_
+#define BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_OBSERVER_H_
+
+#include "base/observer_list.h"
+
+namespace blimp {
+namespace client {
+
+class SettingsObserver {
+ public:
+  virtual ~SettingsObserver() = default;
+
+  // Invoked when enabling or disabling Blimp mode in the Settings.
+  virtual void OnBlimpModeEnabled(bool enable) {}
+
+  // Invoked when enabling or disabling to show the network stats in the
+  // Settings.
+  virtual void OnShowNetworkStatsChanged(bool enable) {}
+
+  // Invoked when enabling or disabling to download the whole document in the
+  // Settings.
+  virtual void OnRecordWholeDocumentChanged(bool enable) {}
+
+  // Invoked when a setting changed that requires the application to restart
+  // before it can take effect.
+  virtual void OnRestartRequired() {}
+
+ protected:
+  SettingsObserver() = default;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(SettingsObserver);
+};
+
+}  // namespace client
+}  // namespace blimp
+
+#endif  // BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_OBSERVER_H_