Fixes for -Wunused-function on Linux, Android and ChromeOS

chrome/browser/chromeos/display/display_preferences.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/chromeos/display/display_preferences.h"
 
 #include "ash/display/display_layout_store.h"
 #include "ash/display/display_manager.h"
 #include "ash/display/display_pref_util.h"
 #include "ash/display/resolution_notification_controller.h"
@@ skipping 59 matching lines @@
 // Returns true id the current user can write display preferences to
 // Local State.
 bool UserCanSaveDisplayPreference() {
   UserManager* user_manager = UserManager::Get();
   return user_manager->IsUserLoggedIn() &&
       (user_manager->IsLoggedInAsRegularUser() ||
        user_manager->IsLoggedInAsLocallyManagedUser() ||
        user_manager->IsLoggedInAsKioskApp());
 }
 
-ash::DisplayController* GetDisplayController() {
-  return ash::Shell::GetInstance()->display_controller();
-}
-
 void LoadDisplayLayouts() {
   PrefService* local_state = g_browser_process->local_state();
   ash::internal::DisplayLayoutStore* layout_store =
       GetDisplayManager()->layout_store();
 
   const base::DictionaryValue* layouts = local_state->GetDictionary(
       prefs::kSecondaryDisplays);
   for (DictionaryValue::Iterator it(*layouts); !it.IsAtEnd(); it.Advance()) {
     ash::DisplayLayout layout;
     if (!ash::DisplayLayout::ConvertFromValue(it.value(), &layout)) {
@@ skipping 206 matching lines @@
                                    const ash::DisplayLayout& layout) {
   StoreDisplayLayoutPref(std::make_pair(id1, id2), layout);
 }
 
 // Stores the given |power_state|.
 void StoreDisplayPowerStateForTest(DisplayPowerState power_state) {
   StoreDisplayPowerState(power_state);
 }
 
 }  // namespace chromeos