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

shell/src/PrefsCommand.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 51 matching lines @@
     std::string pref;
     argumentStream >> pref;
 
     auto current = filterEngine.GetPref(pref);
     if (current.IsUndefined())
       std::cout << "No such preference" << std::endl;
     else if (current.IsString())
     {
       std::string value;
       std::getline(argumentStream, value);
-      filterEngine.SetPref(pref, filterEngine.GetJsEngine()->NewValue(value));
+      filterEngine.SetPref(pref, filterEngine.GetJsEngine().NewValue(value));
     }
     else if (current.IsNumber())
     {
       int64_t value;
       argumentStream >> value;
-      filterEngine.SetPref(pref, filterEngine.GetJsEngine()->NewValue(value));
+      filterEngine.SetPref(pref, filterEngine.GetJsEngine().NewValue(value));
     }
     else if (current.IsBool())
     {
       bool value;
       argumentStream >> value;
-      filterEngine.SetPref(pref, filterEngine.GetJsEngine()->NewValue(value));
+      filterEngine.SetPref(pref, filterEngine.GetJsEngine().NewValue(value));
     }
     else
       std::cout << "Cannot set a preference of unknown type" << std::endl;
   }
   else
     throw NoSuchCommandError(name + " " + action);
 }
 
 std::string PrefsCommand::GetDescription() const
 {
   return "Get and set preferences";
 }
 
 std::string PrefsCommand::GetUsage() const
 {
   return name + " [show PREF|set PREF VALUE]";
 }