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

sync/syncable/base_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/base_transaction.h"
 
 #include "base/debug/trace_event.h"
 #include "sync/syncable/directory.h"
 
+namespace syncer {
 namespace syncable {
 
 void BaseTransaction::Lock() {
   TRACE_EVENT2("sync_lock_contention", "AcquireLock",
                "src_file", from_here_.file_name(),
                "src_func", from_here_.function_name());
 
   directory_->kernel_->transaction_mutex.Acquire();
 }
 
@@ skipping 39 matching lines @@
   TRACE_EVENT_BEGIN2("sync", name_,
                      "src_file", from_here_.file_name(),
                      "src_func", from_here_.function_name());
 }
 
 BaseTransaction::~BaseTransaction() {
   TRACE_EVENT_END0("sync", name_);
 }
 
 }  // namespace syncable
+}  // namespace syncer