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

sync/syncable/syncable_id.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_SYNCABLE_SYNCABLE_ID_H_
 #define SYNC_SYNCABLE_SYNCABLE_ID_H_
 #pragma once
 
 #include <iosfwd>
 #include <limits>
 #include <sstream>
 #include <string>
 
 #include "base/hash_tables.h"
 
 class MockConnectionManager;
 
 namespace base {
 class StringValue;
 }
 
 namespace sql {
 class Statement;
 }
 
+namespace syncer {
 namespace syncable {
 struct EntryKernel;
 class Id;
-}
-
-namespace syncable {
 
 std::ostream& operator<<(std::ostream& out, const Id& id);
 
 // For historical reasons, 3 concepts got everloaded into the Id:
 // 1. A unique, opaque identifier for the object.
 // 2. Flag specifing whether server know about this object.
 // 3. Flag for root.
 //
 // We originally wrapped an integer for this information, but now we use a
 // string. It will have one of three forms:
@@ skipping 78 matching lines @@
   friend std::ostream& operator<<(std::ostream& out, const Id& id);
   friend class MockConnectionManager;
   friend class SyncableIdTest;
 
   std::string s_;
 };
 
 Id GetNullId();
 
 }  // namespace syncable
+}  // namespace syncer
 
 #endif  // SYNC_SYNCABLE_SYNCABLE_ID_H_