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

test/FileSystemJsObject.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 26 matching lines @@
     int statLastModified;
 
     MockFileSystem() : success(true)
     {
     }
 
     std::shared_ptr<std::istream> Read(const std::string& path) const
     {
       if (!success)
         throw std::runtime_error("Unable to read " + path);
-      std::stringstream* const stream = new std::stringstream;
+      const auto stream = std::make_shared<std::stringstream>();
       *stream << contentToRead;
-      return std::shared_ptr<std::istream>(stream);
+      return stream;
     }
 
     void Write(const std::string& path, std::shared_ptr<std::istream> data)
     {
       if (!success)
         throw std::runtime_error("Unable to write to " + path);
       lastWrittenPath = path;
 
       std::stringstream content;
       content << data->rdbuf();
@@ skipping 49 matching lines @@
   typedef std::shared_ptr<MockFileSystem> MockFileSystemPtr;
 
   class FileSystemJsObjectTest : public BaseJsTest
   {
   protected:
     MockFileSystemPtr mockFileSystem;
 
     void SetUp()
     {
       BaseJsTest::SetUp();
-      mockFileSystem = MockFileSystemPtr(new MockFileSystem);
+      mockFileSystem = std::make_shared<MockFileSystem>();
       jsEngine->SetFileSystem(mockFileSystem);
     }
+
+    void TearDown()
+    {
+      mockFileSystem.reset();
+      BaseJsTest::TearDown();
+    }
   };
 }
 
 TEST_F(FileSystemJsObjectTest, Read)
 {
   mockFileSystem->contentToRead = "foo";
   std::string content;
   std::string error;
   ReadFile(jsEngine, content, error);
   ASSERT_EQ("foo", content);
@@ skipping 106 matching lines @@
   ASSERT_ANY_THROW(jsEngine->Evaluate("_fileSystem.stat('', '')"));
 }
 
 TEST_F(FileSystemJsObjectTest, StatError)
 {
   mockFileSystem->success = false;
   jsEngine->Evaluate("_fileSystem.stat('foo', function(r) {result = r})");
   std::this_thread::sleep_for(std::chrono::milliseconds(50));
   ASSERT_NE("", jsEngine->Evaluate("result.error")->AsString());
 }