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

sync/api/sync_change.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 "sync/api/sync_change.h"
 
 #include <ostream>
 
+namespace csync {
+
 SyncChange::SyncChange() : change_type_(ACTION_INVALID) {
 }
 
 SyncChange::SyncChange(SyncChangeType change_type, const SyncData& sync_data)
     : change_type_(change_type),
       sync_data_(sync_data) {
   DCHECK(IsValid());
 }
 
 SyncChange::~SyncChange() {}
@@ skipping 45 matching lines @@
 }
 
 std::string SyncChange::ToString() const {
   return "{ changeType: " + ChangeTypeToString(change_type_) +
       ", syncData: " + sync_data_.ToString() + "}";
 }
 
 void PrintTo(const SyncChange& sync_change, std::ostream* os) {
   *os << sync_change.ToString();
 }
+
+}  // namespace csync