Issue #3593 - Make isolate a fully internal member of the engine

test/Prefs.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 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 14 matching lines @@
   typedef std::shared_ptr<AdblockPlus::FilterEngine> FilterEnginePtr;
 
   class TestFileSystem : public LazyFileSystem
   {
   public:
     std::string prefsContents;
 
     std::shared_ptr<std::istream> Read(const std::string& path) const
     {
       if (path == "prefs.json" && !prefsContents.empty())
-        return std::shared_ptr<std::istream>(new std::istringstream(prefsContents));
+        return std::make_shared<std::istringstream>(prefsContents);
 
       return LazyFileSystem::Read(path);
     }
 
     void Write(const std::string& path, std::shared_ptr<std::istream> content)
     {
       if (path == "prefs.json")
       {
         std::stringstream ss;
         ss << content->rdbuf();
@@ skipping 62 matching lines @@
         jsValuePrefs[entry->first] = jsEngine->NewValue(entry->second);
       }
       // Use a new filter engine
       filterEngine = std::make_shared<AdblockPlus::FilterEngine>(jsEngine, jsValuePrefs);
     }
 
     void Destroy()
     {
       filterEngine.reset();
       ToInternal(jsEngine)->WaitForQuietScheduler();
+      EXPECT_EQ(1, jsEngine.use_count());
       jsEngine.reset();
-      EXPECT_EQ(0, jsEngine.use_count());
     }
   };
 }
 
 TEST_F(PrefsTest, PrefsGetSet)
 {
   ASSERT_EQ("patterns.ini", filterEngine->GetPref("patternsfile")->AsString());
   ASSERT_EQ(24, filterEngine->GetPref("patternsbackupinterval")->AsInt());
   ASSERT_TRUE(filterEngine->GetPref("subscriptions_autoupdate")->AsBool());
   ASSERT_TRUE(filterEngine->GetPref("foobar")->IsUndefined());
@@ skipping 94 matching lines @@
 
   std::this_thread::sleep_for(std::chrono::milliseconds(100));
 
   ASSERT_FALSE(fileSystem->prefsContents.empty());
 
   Reset(preconfiguredPrefs);
 
   ASSERT_TRUE(filterEngine->GetPref("suppress_first_run_page")->IsBool());
   ASSERT_FALSE(filterEngine->GetPref("suppress_first_run_page")->AsBool());
 }