Make JsEngine::Evaluate() return a wrapper for v8::Value to accessdifferent variable types easily

src/JsEngine.cpp

Index: src/JsEngine.cpp
===================================================================
--- a/src/JsEngine.cpp
+++ b/src/JsEngine.cpp
@@ -65,29 +65,28 @@ AdblockPlus::JsError::JsError(const v8::
 
 AdblockPlus::JsEngine::JsEngine(const FileReader* const fileReader,
                                 WebRequest* const webRequest,
                                 ErrorCallback* const errorCallback)
   : fileReader(fileReader), context(CreateContext(*errorCallback, *webRequest))
 {
 }
 
-std::string AdblockPlus::JsEngine::Evaluate(const std::string& source,
+AdblockPlus::JsValuePtr AdblockPlus::JsEngine::Evaluate(const std::string& source,
     const std::string& filename)
 {
   const v8::Locker locker(v8::Isolate::GetCurrent());
   const v8::HandleScope handleScope;
   const v8::Context::Scope contextScope(context);
   const v8::TryCatch tryCatch;
   const v8::Handle<v8::Script> script = CompileScript(source, filename);
   CheckTryCatch(tryCatch);
   v8::Local<v8::Value> result = script->Run();
   CheckTryCatch(tryCatch);
-  v8::String::Utf8Value resultString(result);
-  return std::string(*resultString);
+  return JsValuePtr(new JsValue(v8::Isolate::GetCurrent(), context, result));
 }
 
 void AdblockPlus::JsEngine::Load(const std::string& scriptPath)
 {
   const std::auto_ptr<std::istream> file = fileReader->Read(scriptPath);
   if (!*file)
     throw std::runtime_error("Unable to load script " + scriptPath);
   Evaluate(Slurp(*file));