[Prerender] Restore request priorities when swapped in

chrome/browser/prerender/prerender_nostate_prefetch_browsertest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_split.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/task_scheduler/post_task.h"
 #include "chrome/browser/history/history_service_factory.h"
@@ skipping 266 matching lines @@
 IN_PROC_BROWSER_TEST_F(NoStatePrefetchBrowserTest, PrefetchSimultaneous) {
   RequestCounter second_main_counter;
   CountRequestFor(kPrefetchPage2, &second_main_counter);
   RequestCounter second_script_counter;
   CountRequestFor(kPrefetchScript2, &second_script_counter);
 
   GURL first_url = src_server()->GetURL(MakeAbsolute(kPrefetchPage));
   base::FilePath first_path = ui_test_utils::GetTestFilePath(
       base::FilePath(), base::FilePath().AppendASCII(kPrefetchPage));
 
-  content::BrowserThread::PostTask(
-      content::BrowserThread::IO, FROM_HERE,
-      base::Bind(&test_utils::CreateHangingFirstRequestInterceptorOnIO,
-                 first_url, first_path, base::Closure()));
+  test_utils::CreateHangingFirstRequestInterceptor(
+      first_url, first_path, base::Callback<void(net::URLRequest*)>());
 
   // Start the first prefetch directly instead of via PrefetchFromFile for the
   // first prefetch to avoid the wait on prerender stop.
   GURL first_loader_url = ServeLoaderURL(
       kPrefetchLoaderPath, "REPLACE_WITH_PREFETCH_URL", first_url, "");
   std::vector<FinalStatus> first_expected_status_queue(1,
                                                        FINAL_STATUS_CANCELLED);
   NavigateWithPrerenders(first_loader_url, first_expected_status_queue);
 
   PrefetchFromFile(kPrefetchPage2, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
@@ skipping 296 matching lines @@
   // The SW intercepts kPrefetchPage and replaces it with a body that contains
   // an <img> tage for kPrefetchPng. This verifies that the SW ran correctly by
   // observing the fetch of the image.
   RequestCounter image_counter;
   CountRequestFor(kPrefetchPng, &image_counter);
   PrefetchFromFile(kPrefetchPage, FINAL_STATUS_NOSTATE_PREFETCH_FINISHED);
   image_counter.WaitForCount(1);
 }
 
 }  // namespace prerender