Don't use std::string in the plugin, convert when communicating with the engine

src/plugin/PluginWbPassThrough.cpp

 #include "PluginStdAfx.h"
 
 #include "PluginWbPassThrough.h"
 #include "PluginClient.h"
 #include "PluginClientFactory.h"
 #ifdef SUPPORT_FILTER
 #include "PluginFilter.h"
 #endif
 #include "PluginSettings.h"
 #include "PluginClass.h"
@@ skipping 163 matching lines @@
   CPluginClient* client = CPluginClient::GetInstance();
 
   if (tab && client)
   {
     CString documentUrl = tab->GetDocumentUrl();
     // Page is identical to document => don't block
     if (documentUrl == src)
     {
       // fall through
     }
-    else if (CPluginSettings::GetInstance()->IsPluginEnabled() && !client->IsWhitelistedUrl(ToUtf8String(std::wstring(documentUrl))))
+    else if (CPluginSettings::GetInstance()->IsPluginEnabled() && !client->IsWhitelistedUrl(std::wstring(documentUrl)))
     {
       CString domain = tab->GetDocumentDomain();
 
       contentType = CFilter::contentTypeAny;
 
 #ifdef SUPPORT_FRAME_CACHING
       if ((tab != 0) && (tab->IsFrameCached(src)))
       {
         contentType = CFilter::contentTypeSubdocument;
       }
@@ skipping 168 matching lines @@
   CComPtr<IHttpNegotiate> spHttpNegotiate;
   QueryServiceFromClient(&spHttpNegotiate);
 
   return spHttpNegotiate ? spHttpNegotiate->OnResponse(dwResponseCode, szResponseHeaders, szRequestHeaders, pszAdditionalRequestHeaders) : S_OK;
 }
 
 STDMETHODIMP WBPassthruSink::ReportProgress(ULONG ulStatusCode, LPCWSTR szStatusText)
 {
   return m_spInternetProtocolSink ? m_spInternetProtocolSink->ReportProgress(ulStatusCode, szStatusText) : S_OK;
 }