sync: remove use of protobuf extensions in protocol to reduce static init overhead.

chrome/browser/sync/test/engine/mock_connection_manager.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.
 //
 // Mock ServerConnectionManager class for use in client regression tests.
 
 #include "chrome/browser/sync/test/engine/mock_connection_manager.h"
 
 #include <map>
 
@@ skipping 178 matching lines @@
                                                    bool is_folder) {
   if (use_legacy_bookmarks_protocol_) {
     sync_pb::SyncEntity_BookmarkData* data = entity->mutable_bookmarkdata();
     data->set_bookmark_folder(is_folder);
 
     if (!is_folder) {
       data->set_bookmark_url("http://google.com");
     }
   } else {
     entity->set_folder(is_folder);
-    entity->mutable_specifics()->MutableExtension(sync_pb::bookmark);
+    entity->mutable_specifics()->mutable_bookmark();
     if (!is_folder) {
-      entity->mutable_specifics()->MutableExtension(sync_pb::bookmark)->
+      entity->mutable_specifics()->mutable_bookmark()->
           set_url("http://google.com");
     }
   }
 }
 
 SyncEntity* MockConnectionManager::AddUpdateDirectory(int id,
                                                       int parent_id,
                                                       string name,
                                                       int64 version,
                                                       int64 sync_ts) {
@@ skipping 444 matching lines @@
 }
 
 void MockConnectionManager::SetServerNotReachable() {
   server_status_ = HttpResponse::CONNECTION_UNAVAILABLE;
   server_reachable_ = false;
 
   FOR_EACH_OBSERVER(ServerConnectionEventListener, listeners_,
      OnServerConnectionEvent(
          ServerConnectionEvent(server_status_, server_reachable_)));
 }