Move download filename determintion into a separate class.

chrome/browser/download/download_test_file_activity_observer.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_TEST_FILE_ACTIVITY_OBSERVER_H_
 #define CHROME_BROWSER_DOWNLOAD_DOWNLOAD_TEST_FILE_ACTIVITY_OBSERVER_H_
 
-#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 
 class Profile;
 
 // Observes and overrides file chooser dialog and open activity for a profile.
 // By default, once attached to a profile, this class overrides the default file
 // related activity by replacing the ChromeDownloadManagerDelegate associated
 // with |profile|.
 // NOTE: Again, this overrides the ChromeDownloadManagerDelegate for |profile|.
 class DownloadTestFileActivityObserver {
  public:
   // Attaches to |profile|. By default file chooser dialogs will be disabled
   // once attached. Call EnableFileChooser() to re-enable.
   explicit DownloadTestFileActivityObserver(Profile* profile);
   ~DownloadTestFileActivityObserver();
 
   // Sets whether the file chooser dialog is enabled. If |enable| is false, any
   // attempt to display a file chooser dialog will cause the download to be
   // canceled. Otherwise, attempting to display a file chooser dialog will
   // result in the download continuing with the suggested path.
   void EnableFileChooser(bool enable);
 
   // Returns true if a file chooser dialog was displayed since the last time
   // this method was called.
   bool TestAndResetDidShowFileChooser();
 
  private:
-  class MockDownloadManagerDelegate;
+  class TestDownloadFilePickerFactory;
 
-  scoped_refptr<MockDownloadManagerDelegate> test_delegate_;
+  base::WeakPtr<TestDownloadFilePickerFactory> test_file_picker_factory_;
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_TEST_FILE_ACTIVITY_OBSERVER_H_