PART1: Initiated the SignedSettings refactoring.

chrome/browser/chromeos/cros_settings.h

 // Copyright (c) 2011 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_CROS_SETTINGS_H_
 #define CHROME_BROWSER_CHROMEOS_CROS_SETTINGS_H_
 #pragma once
 
 #include <string>
 #include <vector>
 
 #include "base/hash_tables.h"
 #include "base/memory/singleton.h"
 #include "base/observer_list.h"
 #include "base/threading/non_thread_safe.h"
 #include "chrome/browser/chromeos/cros_settings_names.h"
+#include "chrome/browser/chromeos/cros_settings_provider.h"
 #include "content/common/notification_observer.h"
 
 namespace base {
 template <typename T> struct DefaultLazyInstanceTraits;
+class ListValue;
 class Value;
 }
 
 namespace chromeos {
 
-class CrosSettingsProvider;
-
 // A class manages per-device/global settings.
 class CrosSettings : public base::NonThreadSafe {
  public:
   // Class factory.
   static CrosSettings* Get();
 
   // Helper function to test if given path is a value cros settings name.
   static bool IsCrosSettings(const std::string& path);
 
   // Sets |in_value| to given |path| in cros settings.
   // Note that this takes ownership of |in_value|.
   void Set(const std::string& path, base::Value* in_value);
 
   // Fires system setting change notification.
+  // TODO(pastarmovj): Consider to remove this function from the public
+  // interface.
   void FireObservers(const char* path);
 
   // Gets settings value of given |path| to |out_value|.
-  // Note that the caller owns |out_value| returned.
-  bool Get(const std::string& path, base::Value** out_value) const;
+  const base::Value* GetPref(const std::string& path) const;
+
+  // Gets settings value of given |path| from the trusted store. It will call
+  // the |callback| function with the value of the setting or NULL if it could
+  // not be retrieved.

[Chris Masone, 2011/10/05 18:43:12]

I don't think this contract is true.  Digging all the way down to
UserCrosSettingsTrust::RequestTrustedEntity (which is what you implement
UserCrosSettingsProvider::GetTrusted with), it only calls |callback| if it
cannot get |path|.  If it _can_ get |path|, it deletes the callback and returns
true.

[pastarmovj, 2011/10/13 11:23:02]

Done.

+  bool GetTrusted(const std::string& path,
+                  const base::Closure& callback) const;
 
   // Convenience forms of Set().  These methods will replace any existing
   // value at that path, even if it has a different type.
   void SetBoolean(const std::string& path, bool in_value);
   void SetInteger(const std::string& path, int in_value);
   void SetDouble(const std::string& path, double in_value);
   void SetString(const std::string& path, const std::string& in_value);
 
   // These are convenience forms of Get().  The value will be retrieved
   // and the return value will be true if the path is valid and the value at
   // the end of the path can be returned in the form specified.
   bool GetBoolean(const std::string& path, bool* out_value) const;
   bool GetInteger(const std::string& path, int* out_value) const;
   bool GetDouble(const std::string& path, double* out_value) const;
   bool GetString(const std::string& path, std::string* out_value) const;
+  bool GetList(const std::string& path,
+               const base::ListValue** out_value) const;
 
   // adding/removing of providers
   bool AddSettingsProvider(CrosSettingsProvider* provider);
   bool RemoveSettingsProvider(CrosSettingsProvider* provider);
 
   // If the pref at the given path changes, we call the observer's Observe
   // method with PREF_CHANGED.
   void AddSettingsObserver(const char* path, NotificationObserver* obs);
   void RemoveSettingsObserver(const char* path, NotificationObserver* obs);
 
@@ skipping 14 matching lines @@
   CrosSettings();
   ~CrosSettings();
   friend struct base::DefaultLazyInstanceTraits<CrosSettings>;
 
   DISALLOW_COPY_AND_ASSIGN(CrosSettings);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_CROS_SETTINGS_H_