Refactor preference syncing.

chrome/browser/external_protocol_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/external_protocol_handler.h"
 
 #include <set>
 
 #include "base/logging.h"
 #include "base/message_loop.h"
@@ skipping 155 matching lines @@
     return;
   }
 
   loop->PostTask(FROM_HERE,
       NewRunnableFunction(&platform_util::OpenExternal, url));
 #endif
 }
 
 // static
 void ExternalProtocolHandler::RegisterPrefs(PrefService* prefs) {
-  prefs->RegisterDictionaryPref(prefs::kExcludedSchemes);
+  prefs->RegisterDictionaryPref(prefs::kExcludedSchemes,
+                                false /* don't sync pref */);
 }
 
 // static
 void ExternalProtocolHandler::PermitLaunchUrl() {
   DCHECK_EQ(MessageLoop::TYPE_UI, MessageLoop::current()->type());
   g_accept_requests = true;
 }