[Sync] Move sync/{internal_api,syncable} into syncer namespace

sync/syncable/write_transaction.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/syncable/write_transaction.h"
 
 #include "sync/syncable/directory.h"
 #include "sync/syncable/directory_change_delegate.h"
 #include "sync/syncable/transaction_observer.h"
 #include "sync/syncable/write_transaction_info.h"
 
+namespace syncer {
 namespace syncable {
 
 enum InvariantCheckLevel {
   OFF = 0,
   VERIFY_IN_MEMORY = 1,
   FULL_DB_VERIFICATION = 2
 };
 
 const InvariantCheckLevel kInvariantCheckLevel = VERIFY_IN_MEMORY;
 
@@ skipping 127 matching lines @@
     ENUM_CASE(PURGE_ENTRIES);
     ENUM_CASE(SYNCAPI);
   };
   NOTREACHED();
   return "";
 }
 
 #undef ENUM_CASE
 
 }  // namespace syncable
+}  // namespace syncer