Cleanup parameter passing issues in content/browser/download

content/browser/download/mock_download_manager.cc

 // 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.
 
 #include "content/browser/download/mock_download_manager.h"
 
 #include "content/browser/download/download_create_info.h"
 #include "content/browser/download/download_item_impl.h"
 
 using content::DownloadItem;
@@ skipping 37 matching lines @@
 bool MockDownloadManager::Init(content::BrowserContext* browser_context) {
   return true;
 }
 
 void MockDownloadManager::StartDownload(int32 id) {
 }
 
 void MockDownloadManager::UpdateDownload(int32 download_id,
                                          int64 bytes_so_far,
                                          int64 bytes_per_sec,
-                                         std::string hash_state) {
+                                         const std::string& hash_state) {
 }
 
 void MockDownloadManager::OnResponseCompleted(int32 download_id, int64 size,
                                               const std::string& hash) {
 }
 
 void MockDownloadManager::CancelDownload(int32 download_id) {
 }
 
 void MockDownloadManager::OnDownloadInterrupted(int32 download_id,
                                                 int64 size,
-                                                std::string hash_state,
+                                                const std::string& hash_state,
                                                 InterruptReason reason) {
 }
 
 void MockDownloadManager::OnDownloadRenamedToFinalName(
     int download_id,
     const FilePath& full_path,
     int uniquifier) {
 }
 
 int MockDownloadManager::RemoveDownloadsBetween(const base::Time remove_begin,
@@ skipping 108 matching lines @@
   download->Rename(chosen_file);
 }
 
 DownloadItem* MockDownloadManager::GetActiveDownload(int32 download_id) {
   return GetDownloadItem(download_id);
 }
 
 void MockDownloadManager::SetFileManager(DownloadFileManager* file_manager) {
   file_manager_ = file_manager;
 }