Add pref to enable/disable palette tray.

chrome/browser/chromeos/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/preferences.h"
 
 #include <vector>
 
 #include "ash/autoclick/autoclick_controller.h"
 #include "ash/common/accessibility_types.h"
@@ skipping 264 matching lines @@
   registry->RegisterIntegerPref(
       prefs::kLanguageXkbAutoRepeatDelay,
       language_prefs::kXkbAutoRepeatDelayInMs,
       user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
   registry->RegisterIntegerPref(
       prefs::kLanguageXkbAutoRepeatInterval,
       language_prefs::kXkbAutoRepeatIntervalInMs,
       user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
 
   registry->RegisterBooleanPref(
+      prefs::kEnableStylusTools, true,
+      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  registry->RegisterBooleanPref(
       prefs::kLaunchPaletteOnEjectEvent, true,
       user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
 
   // We don't sync wake-on-wifi related prefs because they are device specific.
   registry->RegisterBooleanPref(prefs::kWakeOnWifiDarkConnect, true);
 
   // 3G first-time usage promo will be shown at least once.
   registry->RegisterBooleanPref(prefs::kShow3gPromoNotification, true);
 
   // Number of times Data Saver prompt has been shown on 3G data network.
@@ skipping 489 matching lines @@
   touch_hud_projection_enabled_.SetValue(enabled);
 }
 
 void Preferences::ActiveUserChanged(const user_manager::User* active_user) {
   if (active_user != user_)
     return;
   ApplyPreferences(REASON_ACTIVE_USER_CHANGED, "");
 }
 
 }  // namespace chromeos