Blimp Settings framework on the c++ side

blimp/client/core/settings/settings.h

Index: blimp/client/core/settings/settings.h
diff --git a/blimp/client/core/settings/settings.h b/blimp/client/core/settings/settings.h
new file mode 100644
index 0000000000000000000000000000000000000000..e98099bfafcb63a5b17e3d4c9a47af29bbd6ddaf
--- /dev/null
+++ b/blimp/client/core/settings/settings.h
@@ -0,0 +1,68 @@
+// 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_H_
+#define BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_H_
+
+#include "base/macros.h"
+#include "base/observer_list.h"
+
+class PrefRegistrySimple;
+class PrefService;
+
+namespace blimp {
+namespace client {
+
+class SettingsFeature;
+class SettingsObserver;
+
+class Settings {
+ public:
+  explicit Settings(PrefService* local_state);
+  virtual ~Settings();
+
+  static void RegisterPrefs(PrefRegistrySimple* registry);
+
+  // TODO(mlliu): pull more settings from java.
+  // Initializes blimp_enabled_, and record_whole_document_ from the command

[David Trainor- moved to gerrit, 2016/09/27 04:10:06]

Maybe don't include this.  I expect it to get out of date really quickly.  wdyt?

[Menglin, 2016/09/30 23:48:57]

Done.

+  // line flags and the PrefService.
+  void InitializeFromCommandLineAndPref();

[David Trainor- moved to gerrit, 2016/09/27 04:10:06]

Can this just happen in the constructor?

[Menglin, 2016/09/30 23:48:57]

Yes.
Then I need to test the constructor because the logic in
InitializeFromCommandLineAndPref() needs to be tested. I make a few adjustment
in the settings_unittest.cc

+
+  void AddObserver(std::unique_ptr<SettingsObserver> observer);

[David Trainor- moved to gerrit, 2016/09/27 04:10:06]

I think giving ownership of the observer is a bit odd here.  It should probably
be a raw pointer.

[Menglin, 2016/09/30 23:48:57]

Done.

+  void RemoveObserver(std::unique_ptr<SettingsObserver> observer) {}

[David Trainor- moved to gerrit, 2016/09/27 04:10:06]

Implement?

[Menglin, 2016/09/30 23:48:57]

Done.

+
+  void SetEnableBlimpMode(bool enable);

[David Trainor- moved to gerrit, 2016/09/27 04:10:06]

Comment on these?  Maybe also include what command line would set them (if one
exists)

[Menglin, 2016/09/30 23:48:57]

Done.

+  void SetRecordWholeDocument(bool enable);
+  void SetShowNetworkStats(bool enable);
+
+  bool blimp_enabled() { return blimp_enabled_; }
+  bool record_whole_document() { return record_whole_document_; }
+  bool show_network_stats() { return show_network_stats_; }
+
+ private:
+  // The pref service used to store persist the settings.
+  PrefService* local_state_;
+
+  // A list of all the observers of the Blimp Settings.
+  std::vector<std::unique_ptr<SettingsObserver>> observers_;
+
+  // blimp_enabled_ is init from command line/PrefService. It can be changed
+  // from UI.
+  bool blimp_enabled_;
+
+  // Used to avoid sending unnecessary messages to engine. SettingsFeature sends
+  // this to the engine.
+  bool record_whole_document_;
+
+  // show_network_stats_ can only be set from UI, and the value is not stored
+  // persistently.
+  bool show_network_stats_;
+
+  DISALLOW_COPY_AND_ASSIGN(Settings);
+};
+
+}  // namespace client
+}  // namespace blimp
+
+#endif  // BLIMP_CLIENT_CORE_SETTINGS_SETTINGS_H_