Issue #1484 - Make PassthroughAPP a pass-through again

src/plugin/passthroughapp/SinkPolicy.h

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 154 matching lines @@
 
 template <class Protocol, class Sink>
 class CustomSinkStartPolicy
 {
 public:
         DECLARE_AGGREGATABLE_PROTSINK(Protocol, Sink)
 
         HRESULT OnStart(LPCWSTR szUrl,
                 IInternetProtocolSink *pOIProtSink, IInternetBindInfo *pOIBindInfo,
                 DWORD grfPI, HANDLE_PTR dwReserved,
-                IInternetProtocol* pTargetProtocol);
+                IInternetProtocol* pTargetProtocol) const;
 
 
         static Sink* GetSink(const Protocol* pProtocol);
         Sink* GetSink() const;
         static Protocol* GetProtocol(const Sink* pSink);
 };
 
 } // end namespace PassthroughAPP
 
 #include "SinkPolicy.inl"
 
 #endif // PASSTHROUGHAPP_SINKPOLICY_H