Move some Chrome-specific code paths out of DownloadManager and into the delegate. Getting rid of...

chrome/browser/download/chrome_download_manager_delegate.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 CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_
 #define CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_
 #pragma once
 
 #include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
+#include "base/task.h"
 #include "chrome/browser/download/download_manager_delegate.h"
 
+class DownloadItem;
+class DownloadManager;
+struct DownloadStateInfo;
+
 // Browser's download manager: manages all downloads and destination view.
-class ChromeDownloadManagerDelegate : public DownloadManagerDelegate {
+class ChromeDownloadManagerDelegate
+    : public base::RefCountedThreadSafe<ChromeDownloadManagerDelegate>,
+      public DownloadManagerDelegate {
  public:
   ChromeDownloadManagerDelegate();
 
+  virtual bool ShouldStartDownload(int32 download_id) OVERRIDE;
+  virtual void ChooseDownloadPath(TabContents* tab_contents,
+                                  const FilePath& suggested_path,
+                                  void* data) OVERRIDE;
+  virtual TabContents* GetAlternativeTabContentsToNotifyForDownload() OVERRIDE;
+  virtual bool ShouldOpenFileBasedOnExtension(const FilePath& path) OVERRIDE;
   virtual void GetSaveDir(TabContents* tab_contents,
                           FilePath* website_save_dir,
                           FilePath* download_save_dir) OVERRIDE;
   virtual void ChooseSavePath(const base::WeakPtr<SavePackage>& save_package,
                               const FilePath& suggested_path,
                               bool can_save_as_complete) OVERRIDE;
-  virtual void ChooseDownloadPath(DownloadManager* download_manager,
-                                  TabContents* tab_contents,
-                                  const FilePath& suggested_path,
-                                  void* data) OVERRIDE;
-  virtual TabContents* GetAlternativeTabContentsToNotifyForDownload(
-      DownloadManager* download_manager) OVERRIDE;
 
   void set_download_manager(DownloadManager* dm) { download_manager_ = dm; }
 
  private:
-  DownloadManager* download_manager_;
+  friend class base::RefCountedThreadSafe<ChromeDownloadManagerDelegate>;
+  virtual ~ChromeDownloadManagerDelegate();
+
+  // Callback function after url is checked with safebrowsing service.
+  void CheckDownloadUrlDone(int32 download_id, bool is_dangerous_url);
+
+  // Callback function after we check whether the referrer URL has been visited
+  // before today.
+  void CheckVisitedReferrerBeforeDone(int32 download_id,
+                                      bool visited_referrer_before);
+
+  // Called on the download thread to check whether the suggested file path
+  // exists.  We don't check if the file exists on the UI thread to avoid UI
+  // stalls from interacting with the file system.
+  void CheckIfSuggestedPathExists(int32 download_id,
+                                  DownloadStateInfo state,
+                                  const FilePath& default_path);
+
+  // Called on the UI thread once it's determined whether the suggested file
+  // path exists.
+  void OnPathExistenceAvailable(int32 download_id,
+                                const DownloadStateInfo& new_state);
+
+  // Returns true if this download should show the "dangerous file" warning.
+  // Various factors are considered, such as the type of the file, whether a
+  // user action initiated the download, and whether the user has explicitly
+  // marked the file type as "auto open".
+  bool IsDangerousFile(const DownloadItem& download,
+                       const DownloadStateInfo& state,
+                       bool visited_referrer_before);
+
+  scoped_refptr<DownloadManager> download_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeDownloadManagerDelegate);
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_CHROME_DOWNLOAD_MANAGER_DELEGATE_H_