Move the download code to new directories:

chrome/browser/download_item_model.h

-// Copyright (c) 2006-2008 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_ITEM_MODEL_H__
-#define CHROME_BROWSER_DOWNLOAD_ITEM_MODEL_H__
-
-#include "chrome/browser/views/download_item_view.h"
-
-class DownloadItem;
-
-// This class is a model class for DownloadItemView. It provides functionality
-// for canceling the downloading, and also the text for displaying downloading
-// status.
-class DownloadItemModel : public DownloadItemView::BaseDownloadItemModel {
- public:
-  DownloadItemModel(DownloadItem* download);
-  virtual ~DownloadItemModel() { }
-
-  // Cancel the downloading.
-  virtual void CancelTask();
-
-  // Get downloading status text.
-  virtual std::wstring GetStatusText();
-
- private:
-  // We query this item for status information.
-  DownloadItem* download_;
-
-  DISALLOW_EVIL_CONSTRUCTORS(DownloadItemModel);
-};
-
-#endif  // CHROME_BROWSER_DOWNLOAD_ITEM_MODEL_H__
-