Guest mode causes certain settings to be hidden.

chrome/browser/ui/webui/options/browser_options_handler.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/ui/webui/options/browser_options_handler.h"
 
 #include <string>
 #include <vector>
 
 #include "apps/app_window.h"
@@ skipping 514 matching lines @@
   }
   if (!username.empty())
     username = gaia::SanitizeEmail(gaia::CanonicalizeEmail(username));
 
   values->SetString("username", username);
 #endif
 
   // Pass along sync status early so it will be available during page init.
   values->Set("syncData", GetSyncStateDictionary().release());
 
-  // The Reset Profile Settings feature makes no sense for an off-the-record
-  // profile (e.g. in Guest mode on Chrome OS), so hide it.
-  values->SetBoolean("enableResetProfileSettings",
-                     !Profile::FromWebUI(web_ui())->IsOffTheRecord());
-
   values->SetString("privacyLearnMoreURL", chrome::kPrivacyLearnMoreURL);
   values->SetString("doNotTrackLearnMoreURL", chrome::kDoNotTrackLearnMoreURL);
 
 #if !defined(OS_CHROMEOS)
   PrefService* pref_service = g_browser_process->local_state();
   values->SetBoolean("metricsReportingEnabledAtStart", pref_service->GetBoolean(
       prefs::kMetricsReportingEnabled));
 #endif
 
 #if defined(OS_CHROMEOS)
@@ skipping 35 matching lines @@
 #if defined(OS_MACOSX)
   values->SetString("macPasswordsWarning",
       l10n_util::GetStringUTF16(IDS_OPTIONS_PASSWORDS_MAC_WARNING));
   values->SetBoolean("multiple_profiles",
       g_browser_process->profile_manager()->GetNumberOfProfiles() > 1);
 #endif
 
   if (ShouldShowMultiProfilesUserList())
     values->Set("profilesInfo", GetProfilesInfoList().release());
 
+  values->SetBoolean("profileIsGuest",
+                     Profile::FromWebUI(web_ui())->IsOffTheRecord());
+
   values->SetBoolean("profileIsSupervised",
                      Profile::FromWebUI(web_ui())->IsSupervised());
 
 #if !defined(OS_CHROMEOS)
   values->SetBoolean(
       "gpuEnabledAtStart",
       g_browser_process->gpu_mode_manager()->initial_gpu_mode_pref());
 #endif
 
 #if defined(ENABLE_SERVICE_DISCOVERY)
@@ skipping 222 matching lines @@
 
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   if (!command_line.HasSwitch(switches::kUserDataDir)) {
     BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
         base::Bind(&BrowserOptionsHandler::CheckAutoLaunch,
                    weak_ptr_factory_.GetWeakPtr(),
                    profile->GetPath()));
   }
 #endif
 
+  // No preferences below this point may be modified by guest profiles.
+  if (Profile::FromWebUI(web_ui())->IsGuestSession())
+    return;
+
   auto_open_files_.Init(
       prefs::kDownloadExtensionsToOpen, prefs,
       base::Bind(&BrowserOptionsHandler::SetupAutoOpenFileTypes,
                  base::Unretained(this)));
   default_zoom_level_.Init(
       prefs::kDefaultZoomLevel, prefs,
       base::Bind(&BrowserOptionsHandler::SetupPageZoomSelector,
                  base::Unretained(this)));
   profile_pref_registrar_.Init(prefs);
   profile_pref_registrar_.Add(
@@ skipping 1018 matching lines @@
   extension = extensions::GetExtensionOverridingProxy(
       Profile::FromWebUI(web_ui()));
   AppendExtensionData("proxy", extension, &extension_controlled);
 
   web_ui()->CallJavascriptFunction("BrowserOptions.toggleExtensionIndicators",
                                    extension_controlled);
 #endif  // defined(OS_WIN)
 }
 
 }  // namespace options