Revert of Enable per thread heap for database thread

third_party/WebKit/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 82 matching lines @@
     DatabaseContext* self = new DatabaseContext(context);
     DatabaseManager::manager().registerDatabaseContext(self);
     return self;
 }
 
 DatabaseContext::DatabaseContext(ExecutionContext* context)
     : ActiveDOMObject(context)
     , m_hasOpenDatabases(false)
     , m_hasRequestedTermination(false)
 {
-    DCHECK(isMainThread());
-
     // ActiveDOMObject expects this to be called to set internal flags.
     suspendIfNeeded();
 
     // For debug accounting only. We must do this before we register the
     // instance. The assertions assume this.
     DatabaseManager::manager().didConstructDatabaseContext();
 }
 
 DatabaseContext::~DatabaseContext()
 {
@@ skipping 84 matching lines @@
 {
     return getExecutionContext()->getSecurityOrigin();
 }
 
 bool DatabaseContext::isContextThread() const
 {
     return getExecutionContext()->isContextThread();
 }
 
 } // namespace blink