Issue #1484 - Remove unused argument from 'WBPassthruSink::OnStart'

src/plugin/PluginWbPassThrough.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 49 matching lines @@
     /* [out] */ LPWSTR *pszAdditionalHeaders);
 
   STDMETHODIMP OnResponse(
     /* [in] */ DWORD dwResponseCode,
     /* [in] */ LPCWSTR szResponseHeaders,
     /* [in] */ LPCWSTR szRequestHeaders,
     /* [out] */ LPWSTR *pszAdditionalRequestHeaders);
 
   HRESULT OnStart(LPCWSTR szUrl, IInternetProtocolSink *pOIProtSink,
     IInternetBindInfo *pOIBindInfo, DWORD grfPI, HANDLE_PTR dwReserved,
-    IInternetProtocol* pTargetProtocol, bool& handled);
+    IInternetProtocol* pTargetProtocol);
 
   HRESULT OnRead(void *pv, ULONG cb, ULONG* pcbRead);
 
   STDMETHODIMP ReportProgress(
     /* [in] */ ULONG ulStatusCode,
     /* [in] */ LPCWSTR szStatusText);
 
   STDMETHODIMP ReportResult(
     /* [in] */ HRESULT hrResult,
     /* [in] */ DWORD dwError,
@@ skipping 13 matching lines @@
   WBPassthru();
   // IInternetProtocolRoot
   STDMETHODIMP Start(LPCWSTR szUrl, IInternetProtocolSink *pOIProtSink,
     IInternetBindInfo *pOIBindInfo, DWORD grfPI, HANDLE_PTR dwReserved) override;
 
   // IInternetProtocol
   STDMETHODIMP Read(/* [in, out] */ void *pv,/* [in] */ ULONG cb,/* [out] */ ULONG *pcbRead) override;
 
   bool m_shouldSupplyCustomContent;
 };