Make ThreadableLoader class to use references

Source/web/WebSharedWorkerImpl.cpp

Index: Source/web/WebSharedWorkerImpl.cpp
diff --git a/Source/web/WebSharedWorkerImpl.cpp b/Source/web/WebSharedWorkerImpl.cpp
index a9db95ce00153e7d3d03259b41ef562c17c14056..3b2fb3d0379046a18f90f189e1078f968eccf9b4 100644
--- a/Source/web/WebSharedWorkerImpl.cpp
+++ b/Source/web/WebSharedWorkerImpl.cpp
@@ -89,11 +89,12 @@ public:
 
     void load(ExecutionContext* loadingContext, const KURL& scriptURL, const Closure& receiveResponseCallback, const Closure& finishCallback)
     {
+        ASSERT(loadingContext);
         m_receiveResponseCallback = receiveResponseCallback;
         m_finishCallback = finishCallback;
         m_scriptLoader->setTargetType(ResourceRequest::TargetIsSharedWorker);
         m_scriptLoader->loadAsynchronously(
-            loadingContext, scriptURL, DenyCrossOriginRequests, this);
+            *loadingContext, scriptURL, DenyCrossOriginRequests, this);
     }
 
     void didReceiveResponse(unsigned long identifier, const ResourceResponse& response) OVERRIDE