Don`t use references to JsEngine to avoid use-after-free errors,switch to shared_ptr instead

include/AdblockPlus/JsValue.h

Index: include/AdblockPlus/JsValue.h
===================================================================
--- a/include/AdblockPlus/JsValue.h
+++ b/include/AdblockPlus/JsValue.h
@@ -1,27 +1,27 @@
 #ifndef ADBLOCKPLUS_JS_VALUE_H
 #define ADBLOCKPLUS_JS_VALUE_H
 
+#include <string>
 #include <vector>
 #include <v8.h>
-#ifdef _MSC_VER
-#include <memory>
-#else
-#include <tr1/memory>
-#endif
+#include "tr1_memory.h"
 
 namespace AdblockPlus
 {
+  class JsValue;
   class JsEngine;
-  class JsValue;
 
   typedef std::tr1::shared_ptr<JsValue> JsValuePtr;
   typedef std::vector<AdblockPlus::JsValuePtr> JsValueList;
 
+  // Forward declaration to avoid including JsEngine.h
+  typedef std::tr1::shared_ptr<JsEngine> JsEnginePtr;
+
   class JsValue
   {
     friend class JsEngine;
     friend class JsObject;
   public:
     virtual ~JsValue();
 
     bool IsUndefined() const;
@@ -49,17 +49,17 @@ namespace AdblockPlus
     inline void SetProperty(const std::string& name, int val)
     {
       SetProperty(name, static_cast<int64_t>(val));
     }
     std::string GetClassName() const;
     JsValuePtr Call(const JsValueList& params = JsValueList(),
         AdblockPlus::JsValuePtr thisPtr = AdblockPlus::JsValuePtr()) const;
   protected:
-    JsValue(JsEngine& jsEngine, v8::Handle<v8::Value> value);
+    JsValue(JsEnginePtr jsEngine, v8::Handle<v8::Value> value);
     void SetProperty(const std::string& name, v8::Handle<v8::Value> val);
 
-    JsEngine& jsEngine;
+    JsEnginePtr jsEngine;
     v8::Persistent<v8::Value> value;
   };
 }
 
 #endif