Issue #1234 - standardize some string conversions

src/plugin/PluginSettings.cpp

 #include "PluginStdAfx.h"
 
 #include <Wbemidl.h>
 #include <time.h>
 #include "PluginSettings.h"
 #include "PluginClient.h"
 #include "PluginSystem.h"
 #include "PluginFilter.h"
 #include "PluginMutex.h"
 #include "../shared/Utils.h"
 #include <memory>
 
 
 // IE functions
 #pragma comment(lib, "iepmapi.lib")
 
 #include <knownfolders.h>
 
 namespace
 {
-  std::wstring CreateDomainWhitelistingFilter(const CString domain)
+  std::wstring CreateDomainWhitelistingFilter(const CString& domain)
   {
-    return std::wstring(L"@@||") + domain.GetString() + std::wstring(L"^$document");
+    return L"@@||" + to_wstring(domain) + L"^$document";
   }
 }
 
 class TSettings
 {
   DWORD processorId;
 
   char sPluginId[44];
 };
 
@@ skipping 236 matching lines @@
 
 CString CPluginSettings::GetAppLocale()
 {
   return to_CString(GetBrowserLanguage());
 }
 
 CString CPluginSettings::GetDocumentationLink()
 {
   return CString(CPluginClient::GetInstance()->GetDocumentationLink().c_str());
 }