Add download item tooltips on linux/win.

chrome/browser/views/download_item_view.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.
 //
 // A ChromeView that implements one download on the Download shelf.
 // Each DownloadItemView contains an application icon, a text label
 // indicating the download's file name, a text label indicating the
 // download's status (such as the number of bytes downloaded so far)
 // and a button for canceling an in progress download, or opening
 // the completed download.
@@ skipping 96 matching lines @@
   struct DropDownImageSet {
     SkBitmap* top;
     SkBitmap* center;
     SkBitmap* bottom;
   };
 
   void OpenDownload();
 
   void LoadIcon();
 
+  virtual bool GetTooltipText(const gfx::Point& p, std::wstring* tooltip);
+
   // Convenience method to paint the 3 vertical bitmaps (bottom, middle, top)
   // that form the background.
   void PaintBitmaps(gfx::Canvas* canvas,
                     const SkBitmap* top_bitmap,
                     const SkBitmap* center_bitmap,
                     const SkBitmap* bottom_bitmap,
                     int x,
                     int y,
                     int height,
                     int width);
@@ skipping 42 matching lines @@
   // Our parent view that owns us.
   DownloadShelfView* parent_;
 
   // Elements of our particular download
   std::wstring status_text_;
   bool show_status_text_;
 
   // The font used to print the file name and status.
   gfx::Font font_;
 
+  // The tooltip.
+  std::wstring tooltip_text_;
+
   // The current state (normal, hot or pushed) of the body and drop-down.
   State body_state_;
   State drop_down_state_;
 
   // In degrees, for downloads with no known total size.
   int progress_angle_;
 
   // The left and right x coordinates of the drop-down button.
   int drop_down_x_left_;
   int drop_down_x_right_;
@@ skipping 57 matching lines @@
   // downloaded file.
   ScopedRunnableMethodFactory<DownloadItemView> reenable_method_factory_;
 
   // The currently running download context menu.
   scoped_ptr<DownloadShelfContextMenuWin> context_menu_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadItemView);
 };
 
 #endif  // CHROME_BROWSER_VIEWS_DOWNLOAD_ITEM_VIEW_H__