Clean forward declaration in public

public/platform/WebIDBDatabase.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 19 matching lines @@
 #include "WebCommon.h"
 #include "WebIDBCursor.h"
 #include "WebIDBMetadata.h"
 #include "public/platform/WebIDBTypes.h"
 
 namespace blink {
 
 class WebData;
 class WebIDBCallbacks;
 class WebIDBDatabaseCallbacks;
-class WebIDBDatabaseError;
 class WebIDBKey;
 class WebIDBKeyPath;
 class WebIDBKeyRange;
 
 // See comment in WebIDBFactory for a high level overview of these classes.
 class WebIDBDatabase {
 public:
     virtual ~WebIDBDatabase() { }
 
     virtual void createObjectStore(long long transactionId, long long objectStoreId, const WebString& name, const WebIDBKeyPath&, bool autoIncrement) { BLINK_ASSERT_NOT_REACHED(); }
@@ skipping 22 matching lines @@
     virtual void clear(long long transactionId, long long objectStoreId, WebIDBCallbacks*) { BLINK_ASSERT_NOT_REACHED(); }
     virtual void ackReceivedBlobs(const WebVector<WebString>& uuids) { BLINK_ASSERT_NOT_REACHED(); }
 
 protected:
     WebIDBDatabase() { }
 };
 
 } // namespace blink
 
 #endif // WebIDBDatabase_h