Cleanup parameter passing issues in content/browser/download

content/browser/download/download_manager_impl.h

 // Copyright (c) 2011 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 CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_MANAGER_IMPL_H_
 #define CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_MANAGER_IMPL_H_
 #pragma once
 
 #include "content/public/browser/download_manager.h"
@@ skipping 29 matching lines @@
                                      DownloadVector* result) OVERRIDE;
   virtual void GetAllDownloads(const FilePath& dir_path,
                                DownloadVector* result) OVERRIDE;
   virtual void SearchDownloads(const string16& query,
                                DownloadVector* result) OVERRIDE;
   virtual bool Init(content::BrowserContext* browser_context) OVERRIDE;
   virtual void StartDownload(int32 id) OVERRIDE;
   virtual void UpdateDownload(int32 download_id,
                               int64 bytes_so_far,
                               int64 bytes_per_sec,
-                              std::string hash_state) OVERRIDE;
+                              const std::string& hash_state) OVERRIDE;
   virtual void OnResponseCompleted(int32 download_id, int64 size,
                                    const std::string& hash) OVERRIDE;
   virtual void CancelDownload(int32 download_id) OVERRIDE;
   virtual void OnDownloadInterrupted(int32 download_id,
                                      int64 size,
-                                     std::string hash_state,
+                                     const std::string& hash_state,
                                      InterruptReason reason) OVERRIDE;
   virtual void OnDownloadRenamedToFinalName(int download_id,
                                             const FilePath& full_path,
                                             int uniquifier) OVERRIDE;
   virtual int RemoveDownloadsBetween(const base::Time remove_begin,
                                      const base::Time remove_end) OVERRIDE;
   virtual int RemoveDownloads(const base::Time remove_begin) OVERRIDE;
   virtual int RemoveAllDownloads() OVERRIDE;
   virtual void DownloadUrl(const GURL& url,
                            const GURL& referrer,
@@ skipping 203 matching lines @@
   DownloadIdFactory* id_factory_;
 
   // TODO(rdsmith): Remove when http://crbug.com/85408 is fixed.
   // For debugging only.
   int64 largest_db_handle_in_history_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadManagerImpl);
 };
 
 #endif  // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_MANAGER_IMPL_H_