Make proxy settings one atomic dictionary in the PrefStores such that modifications are atomic.

chrome/browser/dom_ui/options/advanced_options_handler.cc

 // Copyright (c) 2011 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/dom_ui/options/advanced_options_handler.h"
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
@@ skipping 557 matching lines @@
   bool disabled = !(manager && manager->download_prefs()->IsAutoOpenUsed());
   FundamentalValue value(disabled);
   dom_ui_->CallJavascriptFunction(
       L"options.AdvancedOptions.SetAutoOpenFileTypesDisabledAttribute", value);
 }
 
 void AdvancedOptionsHandler::SetupProxySettingsSection() {
   // Disable the button if proxy settings are managed by a sysadmin or
   // overridden by an extension.
   PrefService* pref_service = dom_ui_->GetProfile()->GetPrefs();
-  const PrefService::Preference* proxy_server =
-      pref_service->FindPreference(prefs::kProxyServer);
-  bool is_extension_controlled = (proxy_server &&
-                                  proxy_server->IsExtensionControlled());
+  const PrefService::Preference* proxy_config =
+      pref_service->FindPreference(prefs::kProxy);
+  bool is_extension_controlled = (proxy_config &&
+                                  proxy_config->IsExtensionControlled());
 
   FundamentalValue disabled(proxy_prefs_->IsManaged() ||
                             is_extension_controlled);
 
   // Get the appropriate info string to describe the button.
   string16 label_str;
   if (is_extension_controlled) {
     label_str = l10n_util::GetStringUTF16(IDS_OPTIONS_EXTENSION_PROXIES_LABEL);
   } else {
     label_str = l10n_util::GetStringFUTF16(IDS_OPTIONS_SYSTEM_PROXIES_LABEL,
@@ skipping 28 matching lines @@
   FundamentalValue useSSL3Value(useSSL3Setting);
   dom_ui_->CallJavascriptFunction(
       L"options.AdvancedOptions.SetUseSSL3CheckboxState",
       useSSL3Value, disabledValue);
   FundamentalValue useTLS1Value(useTLS1Setting);
   dom_ui_->CallJavascriptFunction(
       L"options.AdvancedOptions.SetUseTLS1CheckboxState",
       useTLS1Value, disabledValue);
 }
 #endif