IndexedDB: Have IDBCursor and IDBRequest explicitly break ref cycles

Source/modules/indexeddb/IDBTransaction.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 204 matching lines @@
             RefPtr<IDBRequest> request = *m_requestList.begin();
             m_requestList.remove(request);
             request->abort();
         }
     }
 
     RefPtr<IDBTransaction> selfRef = this;
     backendDB()->abort(m_id);
 }
 
-IDBTransaction::OpenCursorNotifier::OpenCursorNotifier(PassRefPtr<IDBTransaction> transaction, IDBCursor* cursor)
-    : m_transaction(transaction),
-      m_cursor(cursor)
-{
-    m_transaction->registerOpenCursor(m_cursor);
-}
-
-IDBTransaction::OpenCursorNotifier::~OpenCursorNotifier()
-{
-    if (m_cursor)
-        m_transaction->unregisterOpenCursor(m_cursor);
-}
-
-void IDBTransaction::OpenCursorNotifier::cursorFinished()
-{
-    if (m_cursor) {
-        m_transaction->unregisterOpenCursor(m_cursor);
-        m_cursor = 0;
-        m_transaction.clear();
-    }
-}
-
-void IDBTransaction::registerOpenCursor(IDBCursor* cursor)
-{
-    m_openCursors.add(cursor);
-}
-
-void IDBTransaction::unregisterOpenCursor(IDBCursor* cursor)
-{
-    m_openCursors.remove(cursor);
-}
-
-void IDBTransaction::closeOpenCursors()
-{
-    HashSet<IDBCursor*> cursors;
-    cursors.swap(m_openCursors);
-    for (HashSet<IDBCursor*>::iterator i = cursors.begin(); i != cursors.end(); ++i)
-        (*i)->close();
-}
-
 void IDBTransaction::registerRequest(IDBRequest* request)
 {
     ASSERT(request);
     ASSERT(m_state == Active);
     m_requestList.add(request);
 }
 
 void IDBTransaction::unregisterRequest(IDBRequest* request)
 {
     ASSERT(request);
@@ skipping 21 matching lines @@
         m_state = Finishing;
     }
 
     if (isVersionChange()) {
         for (IDBObjectStoreMetadataMap::iterator it = m_objectStoreCleanupMap.begin(); it != m_objectStoreCleanupMap.end(); ++it)
             it->key->setMetadata(it->value);
         m_database->setMetadata(m_previousMetadata);
         m_database->close();
     }
     m_objectStoreCleanupMap.clear();
-    closeOpenCursors();
 
     // Enqueue events before notifying database, as database may close which enqueues more events and order matters.
     enqueueEvent(Event::createBubble(eventNames().abortEvent));
     m_database->transactionFinished(this);
 }
 
 void IDBTransaction::onComplete()
 {
     IDB_TRACE("IDBTransaction::onComplete");
     ASSERT(m_state != Finished);
     m_state = Finishing;
     m_objectStoreCleanupMap.clear();
-    closeOpenCursors();
 
     // Enqueue events before notifying database, as database may close which enqueues more events and order matters.
     enqueueEvent(Event::create(eventNames().completeEvent));
     m_database->transactionFinished(this);
 }
 
 bool IDBTransaction::hasPendingActivity() const
 {
     // FIXME: In an ideal world, we should return true as long as anyone has a or can
     //        get a handle to us or any child request object and any of those have
@@ skipping 114 matching lines @@
 {
     return &m_eventTargetData;
 }
 
 IDBDatabaseBackendInterface* IDBTransaction::backendDB() const
 {
     return db()->backend();
 }
 
 } // namespace WebCore