Use the new callback tracker and delete the old one

webkit/plugins/ppapi/ppb_url_loader_impl.cc

Index: webkit/plugins/ppapi/ppb_url_loader_impl.cc
diff --git a/webkit/plugins/ppapi/ppb_url_loader_impl.cc b/webkit/plugins/ppapi/ppb_url_loader_impl.cc
index d989fcd3569effd01a4cb7e82ecba7567a3155ad..d14cf403be742c55f66ab88866e4382b8e0c9e2c 100644
--- a/webkit/plugins/ppapi/ppb_url_loader_impl.cc
+++ b/webkit/plugins/ppapi/ppb_url_loader_impl.cc
@@ -36,6 +36,7 @@ using ppapi::Resource;
 using ppapi::thunk::EnterResourceNoLock;
 using ppapi::thunk::PPB_URLLoader_API;
 using ppapi::thunk::PPB_URLRequestInfo_API;
+using ppapi::TrackedCallback;
 using WebKit::WebFrame;
 using WebKit::WebString;
 using WebKit::WebURL;
@@ -397,8 +398,7 @@ void PPB_URLLoader_Impl::RegisterCallback(PP_CompletionCallback callback) {
   if (!plugin_module)
     return;
 
-  pending_callback_ = new TrackedCompletionCallback(
-      plugin_module->GetCallbackTracker(), pp_resource(), callback);
+  pending_callback_ = new TrackedCallback(this, callback);
 }
 
 void PPB_URLLoader_Impl::RunCallback(int32_t result) {
@@ -407,10 +407,7 @@ void PPB_URLLoader_Impl::RunCallback(int32_t result) {
     CHECK(main_document_loader_);
     return;
   }
-
-  scoped_refptr<TrackedCompletionCallback> callback;
-  callback.swap(pending_callback_);
-  callback->Run(result);  // Will complete abortively if necessary.
+  TrackedCallback::ClearAndRun(&pending_callback_, result);
 }
 
 size_t PPB_URLLoader_Impl::FillUserBuffer() {