Issue 3594 - remove circular references JsEngine-JsValue-JsEngine

include/AdblockPlus/JsValue.h

 /*
  * 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 114 matching lines @@
         AdblockPlus::JsValuePtr thisPtr = AdblockPlus::JsValuePtr()) const;
 
     /**
      * Invokes the value as a function (see `IsFunction()`) with single
      * parameter.
      * @param arg A single required parameter.
      * @return Value returned by the function.
      */
     JsValuePtr Call(const JsValue& arg) const;
 
-    v8::Local<v8::Value> UnwrapValue() const;
+    v8::Local<v8::Value> UnwrapValue(JsEngine& jsEngine) const;
   protected:
-    JsEnginePtr jsEngine;
+    std::weak_ptr<JsEngine> m_jsEngine;

[Oleksandr, 2016/11/25 10:38:04]

Nit: I don't really see a value in renaming the variable here and below.

[sergei, 2016/11/25 12:04:46]

I thought we finally started to use #pragma once and prefixes for members of
classes in C++.
https://codereview.adblockplus.org/29333474/diff/29345688/compiled/String.h

Actually, it's very helpful in C++. Here in particular it also helped to
eliminate all accidental cases of usage of jsEngine member instead of strong
referenced JsEngine.

m_ is removed.

   private:
-    JsValue(JsEnginePtr jsEngine, v8::Handle<v8::Value> value);
+    JsValue(const std::weak_ptr<JsEngine>& jsEngine, v8::Handle<v8::Value> value);
     void SetProperty(const std::string& name, v8::Handle<v8::Value> val);
-    std::unique_ptr<v8::Persistent<v8::Value>> value;
+    std::unique_ptr<v8::Persistent<v8::Value>> m_value;
   };
 }
 
 #endif