[Sync] Put everything in sync/api into csync namespace

sync/api/sync_change.h

 // 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.
 
 #ifndef SYNC_API_SYNC_CHANGE_H_
 #define SYNC_API_SYNC_CHANGE_H_
 #pragma once
 
 #include <iosfwd>
 #include <string>
 #include <vector>
 
 #include "sync/api/sync_data.h"
 
+namespace csync {
+
 // A SyncChange object reflects a change to a piece of synced data. The change
 // can be either a delete, add, or an update. All data relevant to the change
 // is encapsulated within the SyncChange, which, once created, is immutable.
 // Note: it is safe and cheap to pass these by value or make copies, as they do
 // not create deep copies of their internal data.
 class SyncChange {
  public:
   enum SyncChangeType {
     ACTION_INVALID,
     ACTION_ADD,
@@ skipping 32 matching lines @@
   SyncChangeType change_type_;
 
   // An immutable container for the data of this SyncChange. Whenever
   // SyncChanges are copied, they copy references to this data.
   SyncData sync_data_;
 };
 
 // gmock printer helper.
 void PrintTo(const SyncChange& sync_change, std::ostream* os);
 
+}  // namespace csync
+
 #endif  // SYNC_API_SYNC_CHANGE_H_