Make the DatabaseTracker thread-safe.

WebCore/storage/DatabaseThread.cpp

 /*
  * Copyright (C) 2007, 2008 Apple 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 95 matching lines @@
     LOG(StorageAPI, "About to detach thread %i and clear the ref to DatabaseThread %p, which currently has %i ref(s)", m_threadID, this, refCount());
 
     // Close the databases that we ran transactions on. This ensures that if any transactions are still open, they are rolled back and we don't leave the database in an
     // inconsistent or locked state.
     if (m_openDatabaseSet.size() > 0) {
         // As the call to close will modify the original set, we must take a copy to iterate over.
         DatabaseSet openSetCopy;
         openSetCopy.swap(m_openDatabaseSet);
         DatabaseSet::iterator end = openSetCopy.end();
         for (DatabaseSet::iterator it = openSetCopy.begin(); it != end; ++it)
-           (*it)->close();
+           (*it)->close(true);
     }
 
     // Detach the thread so its resources are no longer of any concern to anyone else
     detachThread(m_threadID);
 
     DatabaseTaskSynchronizer* cleanupSync = m_cleanupSync;
     
     // Clear the self refptr, possibly resulting in deletion
     m_selfRef = 0;
 
@@ skipping 39 matching lines @@
 
 void DatabaseThread::unscheduleDatabaseTasks(Database* database)
 {
     // Note that the thread loop is running, so some tasks for the database
     // may still be executed. This is unavoidable.
     SameDatabasePredicate predicate(database);
     m_queue.removeIf(predicate);
 }
 } // namespace WebCore
 #endif