PART1: Initiated the SignedSettings refactoring.

chrome/browser/chromeos/cros_settings.h

Index: chrome/browser/chromeos/cros_settings.h
diff --git a/chrome/browser/chromeos/cros_settings.h b/chrome/browser/chromeos/cros_settings.h
index cc15f2fe1e72d7b06be4e6ac720604b6bd8fda31..90c8dcd428da318b2c516d11eee0a9d1edbd932b 100644
--- a/chrome/browser/chromeos/cros_settings.h
+++ b/chrome/browser/chromeos/cros_settings.h
@@ -14,17 +14,17 @@
 #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:
@@ -39,11 +39,18 @@ class CrosSettings : public base::NonThreadSafe {
   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.
@@ -59,6 +66,8 @@ class CrosSettings : public base::NonThreadSafe {
   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);