Ensure that scheduled tasks are executed during db thread shutdown

Source/modules/webdatabase/DatabaseContext.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2011 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 180 matching lines @@
     ASSERT(isContextThread());
     Vector<DatabaseBackendBase*> syncDatabases;
     copyToVector(m_openSyncDatabases, syncDatabases);
     m_openSyncDatabases.clear();
     for (size_t i = 0; i < syncDatabases.size(); ++i)
         syncDatabases[i]->closeImmediately();
 }
 
 bool DatabaseContext::stopDatabases(DatabaseTaskSynchronizer* cleanupSync)
 {
+    DatabaseManager::manager().interruptAllDatabasesForContext(executionContext());
+
     stopSyncDatabases();
     if (m_isRegistered) {
         DatabaseManager::manager().unregisterDatabaseContext(this);
         m_isRegistered = false;
     }
 
     // Though we initiate termination of the DatabaseThread here in
     // stopDatabases(), we can't clear the m_databaseThread ref till we get to
     // the destructor. This is because the Databases that are managed by
     // DatabaseThread still rely on this ref between the context and the thread
@@ skipping 24 matching lines @@
 {
     return executionContext()->securityOrigin();
 }
 
 bool DatabaseContext::isContextThread() const
 {
     return executionContext()->isContextThread();
 }
 
 } // namespace WebCore