Make refcounting of IndexedDBFactory threadsafe

content/browser/indexed_db/indexed_db_factory.h

 // Copyright (c) 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 CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_FACTORY_H_
 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_FACTORY_H_
 
 #include <map>
 #include <set>
 
 #include "base/basictypes.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/string16.h"
 #include "content/browser/indexed_db/indexed_db_callbacks.h"
 #include "content/browser/indexed_db/indexed_db_database.h"
 #include "content/browser/indexed_db/indexed_db_database_callbacks.h"
 #include "content/common/content_export.h"
 #include "url/gurl.h"
 
 namespace content {
 
 class IndexedDBBackingStore;
 class IndexedDBContextImpl;
 
 class CONTENT_EXPORT IndexedDBFactory
-    : NON_EXPORTED_BASE(public base::RefCounted<IndexedDBFactory>) {
+    : NON_EXPORTED_BASE(public base::RefCountedThreadSafe<IndexedDBFactory>) {
  public:
   explicit IndexedDBFactory(IndexedDBContextImpl* context);
 
   // Notifications from weak pointers.
   void ReleaseDatabase(const IndexedDBDatabase::Identifier& identifier,
                        const GURL& origin_url,
                        bool forcedClose);
 
   void GetDatabaseNames(scoped_refptr<IndexedDBCallbacks> callbacks,
                         const GURL& origin_url,
@@ skipping 16 matching lines @@
   // Iterates over all databases; for diagnostics only.
   std::vector<IndexedDBDatabase*> GetOpenDatabasesForOrigin(
       const GURL& origin_url) const;
 
   bool IsBackingStoreOpenForTesting(const GURL& origin_url) const;
 
   // Called by the IndexedDBContext destructor so the factory can do cleanup.
   void ContextDestroyed();
 
  protected:
-  friend class base::RefCounted<IndexedDBFactory>;
+  friend class base::RefCountedThreadSafe<IndexedDBFactory>;
 
   virtual ~IndexedDBFactory();
 
   virtual scoped_refptr<IndexedDBBackingStore> OpenBackingStore(
       const GURL& origin_url,
       const base::FilePath& data_directory,
       blink::WebIDBDataLoss* data_loss,
       std::string* data_loss_reason,
       bool* disk_full);
 
@@ skipping 15 matching lines @@
   typedef std::map<GURL, scoped_refptr<IndexedDBBackingStore> >
       IndexedDBBackingStoreMap;
   IndexedDBBackingStoreMap backing_store_map_;
 
   std::set<scoped_refptr<IndexedDBBackingStore> > session_only_backing_stores_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_FACTORY_H_