Issue #4692 - Move responsibility for engine reference from tasks to scheduler

src/WebRequestJsObject.cpp

Index: src/WebRequestJsObject.cpp
===================================================================
--- a/src/WebRequestJsObject.cpp
+++ b/src/WebRequestJsObject.cpp
@@ -30,6 +30,7 @@
 namespace
 {
   class WebRequestTask
+    : public TaskFunctionInterface
   {
   public:
     WebRequestTask(
@@ -38,13 +39,12 @@
       AdblockPlus::HeaderList headers,
       V8PersistentNG<v8::Function> callbackFunction
     )
-      : jsEngine(engine->shared_from_this()),
+      : engine(engine),
       url(url), headers(headers), callbackFunction(callbackFunction)
     {}
 
-    void operator()()
+    void operator()() override
     {
-      auto engine = ToInternal(jsEngine); // temporary statement while task keeps its own engine alive
       /*
        * Synchronous HTTP GET request is arbitrary-duration and not interruptible
        */
@@ -77,7 +77,7 @@
     /**
      * Engine pointer keeps engine in existence across thread boundary
      */
-    AdblockPlus::JsEnginePtr jsEngine;
+    JsEngineInternal *engine;
     std::string url;
     AdblockPlus::HeaderList headers;
     V8PersistentNG<v8::Function> callbackFunction;
@@ -107,7 +107,6 @@
   /*
    * Factory block for WebRequest tasks.
    */
-  std::shared_ptr<WebRequestTask> task;
   try
   {
     std::string url;
@@ -152,8 +151,13 @@
     {
       throw std::runtime_error("Third argument to GET must be a function");
     }
-    task = std::make_shared<WebRequestTask>(engine, url, headers, 
+    WebRequestTask task(engine, url, headers,
       V8PersistentNG<v8::Function>(engine->GetIsolate(), v8::Local<v8::Function>::Cast(arguments[2])));
+    /*
+    * Run the task
+    */
+    engine->ScheduleTask(std::move(task), ImmediateSingleUseThread);
+    return v8::Undefined();
   }
   catch (const std::exception& e)
   {
@@ -161,9 +165,4 @@
     v8::Isolate* isolate = arguments.GetIsolate();
     return v8::ThrowException(ToV8String(isolate, e.what()));
   }
-  /*
-   * Run the task
-   */
-  engine->Schedule(AdblockPlus::MakeHeapFunction(task), AdblockPlus::ImmediateSingleUseThread);
-  return v8::Undefined();
 }