Downloads: replace BrowserThread::FILE with task scheduler.

chrome/browser/download/download_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 "chrome/browser/download/download_browsertest.h"
 
 #include <stdint.h>
 
 #include <memory>
 #include <set>
@@ skipping 898 matching lines @@
       downloads_expected++;
       observer->WaitForFinished();
       DownloadItem::DownloadState final_state =
           (download_info.reason == content::DOWNLOAD_INTERRUPT_REASON_NONE) ?
               DownloadItem::COMPLETE :
               DownloadItem::INTERRUPTED;
       EXPECT_EQ(1u, observer->NumDownloadsSeenInState(final_state));
     }
 
     // Wait till the |DownloadFile|s are destroyed.
-    content::RunAllPendingInMessageLoop(content::BrowserThread::FILE);
-    content::RunAllPendingInMessageLoop(content::BrowserThread::UI);
+    content::RunAllBlockingPoolTasksUntilIdle();
 
     // Validate that the correct files were downloaded.
     download_items.clear();
     GetDownloads(browser(), &download_items);
     ASSERT_EQ(downloads_expected, download_items.size());
 
     if (download_info.show_download_item) {
       // Find the last download item.
       DownloadItem* item = download_items[0];
       for (size_t d = 1; d < downloads_expected; ++d) {
@@ skipping 2946 matching lines @@
           browser(), 1,
           content::DownloadTestObserver::ON_DANGEROUS_DOWNLOAD_DENY));
   ui_test_utils::NavigateToURL(browser(), extension_url);
 
   observer->WaitForFinished();
 
   // Download shelf should close.
   EXPECT_FALSE(browser()->window()->IsDownloadShelfVisible());
 }
 #endif  // defined(OS_CHROMEOS)