Clean up forward declarations in Source/modules

Source/modules/webdatabase/SQLStatement.h

 /*
  * Copyright (C) 2007, 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
@@ skipping 18 matching lines @@
 #define SQLStatement_h
 
 #include "modules/webdatabase/sqlite/SQLValue.h"
 #include "modules/webdatabase/SQLResultSet.h"
 #include "wtf/Forward.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class Database;
-class SQLError;
 class SQLStatementBackend;
 class SQLStatementCallback;
 class SQLStatementErrorCallback;
 class SQLTransaction;
 
 class SQLStatement final : public GarbageCollectedFinalized<SQLStatement> {
 public:
     static SQLStatement* create(Database*, SQLStatementCallback*, SQLStatementErrorCallback*);
     ~SQLStatement();
     void trace(Visitor*);
@@ skipping 14 matching lines @@
     Member<SQLStatementBackend> m_backend;
 
     Member<SQLStatementCallback> m_statementCallback;
     Member<SQLStatementErrorCallback> m_statementErrorCallback;
     int m_asyncOperationId;
 };
 
 } // namespace blink
 
 #endif // SQLStatement_h