Issue 5450 - don't expose std::shared_ptr<JsEngine>

shell/src/Main.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 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 47 matching lines @@
   {
     AdblockPlus::AppInfo appInfo;
     appInfo.version = "1.0";
     appInfo.name = "abpshell";
     appInfo.application = "standalone";
     appInfo.applicationVersion = "1.0";
     appInfo.locale = "en-US";
 
     AdblockPlus::Platform platform;
     platform.SetUpJsEngine(appInfo);
-    AdblockPlus::JsEnginePtr jsEngine = platform.GetJsEngine();
+    AdblockPlus::JsEngine& jsEngine = platform.GetJsEngine();
     auto filterEngine = platform.GetFilterEngine();
 
     CommandMap commands;
     Add(commands, new GcCommand(jsEngine));
     Add(commands, new HelpCommand(commands));
     Add(commands, new FiltersCommand(*filterEngine));
     Add(commands, new SubscriptionsCommand(*filterEngine));
     Add(commands, new MatchesCommand(*filterEngine));
     Add(commands, new PrefsCommand(*filterEngine));
 
@@ skipping 16 matching lines @@
         std::cout << error.what() << std::endl;
       }
     }
   }
   catch (const std::exception& e)
   {
     std::cerr << "Exception: " << e.what() << std::endl;
   }
   return 0;
 }