[sql] QuotaDatabase schema upgrade doesn't use transactions right.

storage/browser/quota/quota_database.h

 // Copyright 2013 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 STORAGE_BROWSER_QUOTA_QUOTA_DATABASE_H_
 #define STORAGE_BROWSER_QUOTA_QUOTA_DATABASE_H_
 
 #include <set>
 #include <string>
 
@@ skipping 144 matching lines @@
   void ScheduleCommit();
 
   bool FindOriginUsedCount(const GURL& origin,
                            StorageType type,
                            int* used_count);
 
   bool LazyOpen(bool create_if_needed);
   bool EnsureDatabaseVersion();
   bool ResetSchema();
   bool UpgradeSchema(int current_version);
+  bool InsertOrReplaceHostQuota(
+      const std::string& host, StorageType type, int64 quota);
 
   static bool CreateSchema(
       sql::Connection* database,
       sql::MetaTable* meta_table,
       int schema_version, int compatible_version,
       const TableSchema* tables, size_t tables_size,
       const IndexSchema* indexes, size_t indexes_size);
 
   // |callback| may return false to stop reading data.
   bool DumpQuotaTable(const QuotaTableCallback& callback);
@@ skipping 13 matching lines @@
 
   static const TableSchema kTables[];
   static const IndexSchema kIndexes[];
 
   DISALLOW_COPY_AND_ASSIGN(QuotaDatabase);
 };
 
 }  // namespace storage
 
 #endif  // STORAGE_BROWSER_QUOTA_QUOTA_DATABASE_H_