chrome: Cleanup class/struct forward declarations

chrome/browser/download/download_service.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.
 
 #ifndef CHROME_BROWSER_DOWNLOAD_DOWNLOAD_SERVICE_H_
 #define CHROME_BROWSER_DOWNLOAD_DOWNLOAD_SERVICE_H_
 
 #include <memory>
 
 #include "base/macros.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "extensions/features/features.h"
 
 class ChromeDownloadManagerDelegate;
 class DownloadHistory;
 class ExtensionDownloadsEventRouter;
-class Profile;
 
 namespace content {
 class DownloadManager;
 }
 
 namespace extensions {
 class ExtensionDownloadsEventRouter;
 }
 
 // Abstract base class for the download service; see DownloadServiceImpl for
@@ skipping 40 matching lines @@
 
   // Returns false if at least one extension has disabled the shelf, true
   // otherwise.
   virtual bool IsShelfEnabled() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DownloadService);
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_SERVICE_H_