Inherit EventTarget interface instead of duplicating its code

Source/modules/indexeddb/IDBDatabase.h

 /*
  * 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 30 matching lines @@
 #include "wtf/RefCounted.h"
 #include "wtf/RefPtr.h"
 
 namespace WebCore {
 
 class DOMError;
 class ScriptExecutionContext;
 
 typedef int ExceptionCode;
 
-class IDBDatabase : public RefCounted<IDBDatabase>, public ScriptWrappable, public EventTarget, public ActiveDOMObject {
+class IDBDatabase : public EventTarget, public RefCounted<IDBDatabase>, public ScriptWrappable, public ActiveDOMObject {
 public:
     static PassRefPtr<IDBDatabase> create(ScriptExecutionContext*, PassRefPtr<IDBDatabaseBackendInterface>, PassRefPtr<IDBDatabaseCallbacks>);
     ~IDBDatabase();
 
     void setMetadata(const IDBDatabaseMetadata& metadata) { m_metadata = metadata; }
     void indexCreated(int64_t objectStoreId, const IDBIndexMetadata&);
     void indexDeleted(int64_t objectStoreId, int64_t indexId);
     void transactionCreated(IDBTransaction*);
     void transactionFinished(IDBTransaction*);
 
@@ skipping 73 matching lines @@
     // Keep track of the versionchange events waiting to be fired on this
     // database so that we can cancel them if the database closes.
     Vector<RefPtr<Event> > m_enqueuedEvents;
 
     RefPtr<IDBDatabaseCallbacks> m_databaseCallbacks;
 };
 
 } // namespace WebCore
 
 #endif // IDBDatabase_h