Bug 1111737. r=smaug

dom/base/nsScriptLoader.cpp

@@ -819,7 +819,12 @@ NotifyOffThreadScriptLoadCompletedRunnable::Run()
 {
   MOZ_ASSERT(NS_IsMainThread());
 
-  nsresult rv = mLoader->ProcessOffThreadRequest(mRequest, &mToken);
+  // We want these to be dropped on the main thread, once we return from this
+  // function.
+  nsRefPtr<nsScriptLoadRequest> request = mRequest.forget();
+  nsRefPtr<nsScriptLoader> loader = mLoader.forget();
+
+  nsresult rv = loader->ProcessOffThreadRequest(request, &mToken);
 
   if (mToken) {
     // The result of the off thread parse was not actually needed to process