Added DownloadProcessHandle class.

chrome/browser/download/download_manager.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.
 //
 // 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 profile in Chrome.
 //
 // Download observers:
@@ skipping 24 matching lines @@
 
 #include "base/basictypes.h"
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "base/scoped_ptr.h"
 #include "base/time.h"
 #include "chrome/browser/download/download_status_updater_delegate.h"
+#include "chrome/browser/download/download_process_handle.h"
 #include "chrome/browser/ui/shell_dialogs.h"
 #include "content/browser/browser_thread.h"
 
 class DownloadFileManager;
 class DownloadHistory;
 class DownloadItem;
 class DownloadPrefs;
 class DownloadStatusUpdater;
 class GURL;
 class Profile;
@@ skipping 135 matching lines @@
   // Remove a download observer from ourself.
   void RemoveObserver(Observer* observer);
 
   // Methods called on completion of a query sent to the history system.
   void OnQueryDownloadEntriesComplete(
       std::vector<DownloadCreateInfo>* entries);
   void OnCreateDownloadEntryComplete(
       DownloadCreateInfo info, int64 db_handle);
 
   // Display a new download in the appropriate browser UI.
-  void ShowDownloadInBrowser(const DownloadCreateInfo& info,
+  void ShowDownloadInBrowser(DownloadProcessHandle process_handle,

[Paweł Hajdan Jr., 2011/05/09 19:47:31]

nit: Why not a pointer?

[ahendrickson, 2011/05/10 18:04:43]

Done.

This function is only called from within one thread, so it's safe to pass in a
pointer.

                              DownloadItem* download);
 
   // The number of in progress (including paused) downloads.
   int in_progress_count() const {
     return static_cast<int>(in_progress_.size());
   }
 
   Profile* profile() { return profile_; }
 
   DownloadHistory* download_history() { return download_history_.get(); }
@@ skipping 71 matching lines @@
   // suggested file path exists.
   void OnPathExistenceAvailable(DownloadCreateInfo* info);
 
   // Called back after a target path for the file to be downloaded to has been
   // determined, either automatically based on the suggested file name, or by
   // the user in a Save As dialog box.
   void AttachDownloadItem(DownloadCreateInfo* info);
 
   // Download cancel helper function.
   void DownloadCancelledInternal(int download_id,
-                                 int render_process_id,
-                                 int request_id);
+                                 DownloadProcessHandle process_handle);

[Paweł Hajdan Jr., 2011/05/09 19:47:31]

nit: Why not a pointer?

[ahendrickson, 2011/05/10 18:04:43]

Because it is ultimately passed to another thread, and this way we don't have to
worry about object lifetimes.

 
   // All data has been downloaded.
   // |hash| is sha256 hash for the downloaded file. It is empty when the hash
   // is not available.
   void OnAllDataSaved(int32 download_id, int64 size, const std::string& hash);
 
   // An error occurred in the download.
   void OnDownloadError(int32 download_id, int64 size, int os_error);
 
   // Updates the app icon about the overall download progress.
   void UpdateAppIcon();
 
   // Makes the ResourceDispatcherHost pause/un-pause a download request.
   // Called on the IO thread.
   void PauseDownloadRequest(ResourceDispatcherHost* rdh,
-                            int render_process_id,
-                            int request_id,
+                            DownloadProcessHandle process_handle,

[Paweł Hajdan Jr., 2011/05/09 19:47:31]

nit: Why not a pointer?

[ahendrickson, 2011/05/10 18:04:43]

Because it's called from other threads, and this way we don't have to worry
about object lifetimes.

                             bool pause);
 
   // Inform observers that the model has changed.
   void NotifyModelChanged();
 
   DownloadItem* GetDownloadItem(int id);
 
   // Debugging routine to confirm relationship between below
   // containers; no-op if NDEBUG.
   void AssertContainersConsistent() const;
@@ skipping 72 matching lines @@
   // The "Save As" dialog box used to ask the user where a file should be
   // saved.
   scoped_refptr<SelectFileDialog> select_file_dialog_;
 
   scoped_ptr<OtherDownloadManagerObserver> other_download_manager_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadManager);
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_MANAGER_H_