Disable modifying extensions when in managed mode.

chrome/browser/extensions/extension_prefs.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/extensions/extension_prefs.h"
 
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/admin_policy.h"
@@ skipping 635 matching lines @@
   return ReadExtensionPrefBoolean(extension_id, kPrefAppNotificationDisbaled);
 }
 
 void ExtensionPrefs::SetAppNotificationDisabled(
    const std::string& extension_id, bool value) {
   DCHECK(Extension::IdIsValid(extension_id));
   UpdateExtensionPref(extension_id, kPrefAppNotificationDisbaled,
                       Value::CreateBooleanValue(value));
 }
 
-std::string ExtensionPrefs::GetPolicyProviderName() const {
+std::string ExtensionPrefs::GetDebugPolicyProviderName() const {
+#ifdef NDEBUG
+  NOTREACHED();
+  return std::string();
+#else
   return "admin policy black/white/forcelist, via the ExtensionPrefs";
+#endif
 }
 
 bool ExtensionPrefs::UserMayLoad(const extensions::Extension* extension,
                                  string16* error) const {
 
   const base::ListValue* blacklist =
       prefs_->GetList(prefs::kExtensionInstallDenyList);
   const base::ListValue* whitelist =
       prefs_->GetList(prefs::kExtensionInstallAllowList);
   return extensions::admin_policy::UserMayLoad(blacklist, whitelist, extension,
@@ skipping 1211 matching lines @@
                             PrefService::UNSYNCABLE_PREF);
   prefs->RegisterInt64Pref(prefs::kLastExtensionsUpdateCheck,
                            0,  // default value
                            PrefService::UNSYNCABLE_PREF);
   prefs->RegisterInt64Pref(prefs::kNextExtensionsUpdateCheck,
                            0,  // default value
                            PrefService::UNSYNCABLE_PREF);
   prefs->RegisterListPref(prefs::kExtensionAllowedInstallSites,
                           PrefService::UNSYNCABLE_PREF);
 }