Fix updating

src/engine/Updater.cpp

 #include <functional>
 #include <memory>
 #include <sstream>
 
 #include <Windows.h>
 
 #include <AdblockPlus/FileSystem.h>
 #include <AdblockPlus/WebRequest.h>
 
 #include "../shared/AutoHandle.h"
@@ skipping 58 matching lines @@
     HINSTANCE instance = ShellExecuteW(NULL, operation, msiexec.c_str(), params.c_str(), NULL, SW_HIDE);
     if (reinterpret_cast<int>(instance) <= 32)
       return false;
 
     // As far as we are concerned everything is fine - MSI service will handle
     // further errors.
     return true;
   }
 }
 
-Updater::Updater(AdblockPlus::JsEnginePtr jsEngine, const std::string& url)
-    : jsEngine(jsEngine), url(url), tempFile(GetAppDataPath() + L"\\update.msi")
+Updater::Updater(AdblockPlus::JsEnginePtr jsEngine)
+    : jsEngine(jsEngine), tempFile(GetAppDataPath() + L"\\update.msi")
 {
 }
 
+void Updater::SetUrl(const std::string& url)
+{
+  this->url = url;
+}
+
 void Updater::Update()
 {
   Debug("Downloading update: " + url);
   ThreadCallbackType* callback = new ThreadCallbackType(std::bind(&Updater::Download, this));
   ::CreateThread(NULL, 0, reinterpret_cast<LPTHREAD_START_ROUTINE>(&RunThread), callback, 0, NULL);
 }
 
 void Updater::Download()
 {
   AdblockPlus::ServerResponse response = jsEngine->GetWebRequest()->GET(url, AdblockPlus::HeaderList());
@@ skipping 42 matching lines @@
     {
       DebugLastError("Failed to install update");
       Dictionary* dictionary = Dictionary::GetInstance();
       MessageBoxW(
         0, dictionary->Lookup("updater", "install-error-text").c_str(),
         dictionary->Lookup("updater", "install-error-title").c_str(),
         MB_OK | MB_ICONEXCLAMATION);
     }
   }
 }