PART1: Initiated the SignedSettings refactoring.

chrome/browser/chromeos/login/user_controller.cc

Index: chrome/browser/chromeos/login/user_controller.cc
diff --git a/chrome/browser/chromeos/login/user_controller.cc b/chrome/browser/chromeos/login/user_controller.cc
index 069cdc98396eb3f03d1fe9a15478750a6fed19e0..75ad29f8c48104d60f3e689b057ac862b3fe0fd7 100644
--- a/chrome/browser/chromeos/login/user_controller.cc
+++ b/chrome/browser/chromeos/login/user_controller.cc
@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "base/utf_string_conversions.h"
+#include "chrome/browser/chromeos/cros_settings.h"
 #include "chrome/browser/chromeos/login/existing_user_view.h"
 #include "chrome/browser/chromeos/login/guest_user_view.h"
 #include "chrome/browser/chromeos/login/helper.h"
@@ -16,7 +17,6 @@
 #include "chrome/browser/chromeos/login/username_view.h"
 #include "chrome/browser/chromeos/login/wizard_accessibility_helper.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
-#include "chrome/browser/chromeos/user_cros_settings_provider.h"
 #include "grit/generated_resources.h"
 #include "grit/theme_resources.h"
 #include "third_party/cros_system_api/window_manager/chromeos_wm_ipc_enums.h"
@@ -55,6 +55,16 @@ void CloseWindow(views::Widget* window) {
     window->CloseNow();
 }
 
+// Helper function to initialize the |is_owner_| const field of UserController.
+bool VerifyOwnership(const std::string& email) {
+  // Empty owner string means that owner hasn't been cached yet, not that owner
+  // has an empty email.
+  // TODO(pastarmovj): Consider switching to TrustedGet here.
+  std::string owner;
+  return CrosSettings::Get()->GetString(kDeviceOwner, &owner) &&
+         (email == owner);
+}
+
 }  // namespace
 
 // WidgetDelegate implementation for the Widget used for the controls.
@@ -125,9 +135,7 @@ UserController::UserController(Delegate* delegate,
       is_user_selected_(false),
       is_new_user_(false),
       is_guest_(false),
-      // Empty 'cached_owner()' means that owner hasn't been cached yet, not
-      // that owner has an empty email.
-      is_owner_(user.email() == UserCrosSettingsProvider::cached_owner()),
+      is_owner_(VerifyOwnership(user.email())),
       show_name_tooltip_(false),
       user_(user),
       delegate_(delegate),