Move app/sql/* files to sql/ directory.

app/sql/transaction.h

-// Copyright (c) 2009 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 APP_SQL_TRANSACTION_H_
-#define APP_SQL_TRANSACTION_H_
-#pragma once
-
-#include "base/basictypes.h"
-
-namespace sql {
-
-class Connection;
-
-class Transaction {
- public:
-  // Creates the scoped transaction object. You MUST call Begin() to begin the
-  // transaction. If you have begun a transaction and not committed it, the
-  // constructor will roll back the transaction. If you want to commit, you
-  // need to manually call Commit before this goes out of scope.
-  explicit Transaction(Connection* connection);
-  ~Transaction();
-
-  // Returns true when there is a transaction that has been successfully begun.
-  bool is_open() const { return is_open_; }
-
-  // Begins the transaction. This uses the default sqlite "deferred" transaction
-  // type, which means that the DB lock is lazily acquired the next time the
-  // database is accessed, not in the begin transaction command.
-  //
-  // Returns false on failure. Note that if this fails, you shouldn't do
-  // anything you expect to be actually transactional, because it won't be!
-  bool Begin();
-
-  // Rolls back the transaction. This will happen automatically if you do
-  // nothing when the transaction goes out of scope.
-  void Rollback();
-
-  // Commits the transaction, returning true on success. This will return
-  // false if sqlite could not commit it, or if another transaction in the
-  // same outermost transaction has been rolled back (which necessitates a
-  // rollback of all transactions in that outermost one).
-  bool Commit();
-
- private:
-  Connection* connection_;
-
-  // True when the transaction is open, false when it's already been committed
-  // or rolled back.
-  bool is_open_;
-
-  DISALLOW_COPY_AND_ASSIGN(Transaction);
-};
-
-}  // namespace sql
-
-#endif  // APP_SQL_TRANSACTION_H_