Revert of Enable per thread heap for database thread

third_party/WebKit/Source/modules/webdatabase/Database.cpp

 /*
  * Copyright (C) 2013 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 197 matching lines @@
     , m_name(name.isolatedCopy())
     , m_expectedVersion(expectedVersion.isolatedCopy())
     , m_displayName(displayName.isolatedCopy())
     , m_estimatedSize(estimatedSize)
     , m_guid(0)
     , m_opened(0)
     , m_new(false)
     , m_transactionInProgress(false)
     , m_isTransactionQueueEnabled(true)
 {
-    DCHECK(isMainThread());
     m_contextThreadSecurityOrigin = m_databaseContext->getSecurityOrigin()->isolatedCopy();
 
     m_databaseAuthorizer = DatabaseAuthorizer::create(infoTableName);
 
     if (m_name.isNull())
         m_name = "";
 
     {
         SafePointAwareMutexLocker locker(guidMutex());
         m_guid = guidForOriginAndName(getSecurityOrigin()->toString(), name);
@@ skipping 674 matching lines @@
         return m_databaseThreadSecurityOrigin.get();
     return 0;
 }
 
 bool Database::opened()
 {
     return static_cast<bool>(acquireLoad(&m_opened));
 }
 
 } // namespace blink