Remove #pragma once from content

content/public/browser/download_manager.h

 // 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.
 //
 // The DownloadManager object manages the process of downloading, including
 // updates to the history system and providing the information for displaying
 // the downloads view in the Destinations tab. There is one DownloadManager per
 // active browser context in Chrome.
 //
 // Download observers:
 // Objects that are interested in notifications about new downloads, or progress
 // updates for a given download must implement one of the download observer
 // interfaces:
 //   DownloadManager::Observer:
 //     - allows observers, primarily views, to be notified when changes to the
 //       set of all downloads (such as new downloads, or deletes) occur
 // Use AddObserver() / RemoveObserver() on the appropriate download object to
 // receive state updates.
 //
 // Download state persistence:
 // The DownloadManager uses the history service for storing persistent
 // information about the state of all downloads. The history system maintains a
 // separate table for this called 'downloads'. At the point that the
 // DownloadManager is constructed, we query the history service for the state of
 // all persisted downloads.
 
 #ifndef CONTENT_PUBLIC_BROWSER_DOWNLOAD_MANAGER_H_
 #define CONTENT_PUBLIC_BROWSER_DOWNLOAD_MANAGER_H_
-#pragma once
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/sequenced_task_runner_helpers.h"
 #include "base/time.h"
@@ skipping 208 matching lines @@
  protected:
   virtual ~DownloadManager() {}
 
  private:
   friend class base::RefCountedThreadSafe<DownloadManager>;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_DOWNLOAD_MANAGER_H_