Reland DownloadItem::Observer::OnDownloadDestroyed() replaces DownloadItem::REMOVING

chrome/browser/ui/views/download/download_item_view.h

Index: chrome/browser/ui/views/download/download_item_view.h
diff --git a/chrome/browser/ui/views/download/download_item_view.h b/chrome/browser/ui/views/download/download_item_view.h
index 342f5386ed6833626a47c02370055bb0f5170132..cf267e91f18f7823dc138893a524bc572e035da9 100644
--- a/chrome/browser/ui/views/download/download_item_view.h
+++ b/chrome/browser/ui/views/download/download_item_view.h
@@ -74,9 +74,10 @@ class DownloadItemView : public views::ButtonListener,
   // Returns the DownloadItem model object belonging to this item.
   content::DownloadItem* download() const { return download_; }
 
-  // DownloadObserver method
+  // DownloadObserver methods
   virtual void OnDownloadUpdated(content::DownloadItem* download) OVERRIDE;
   virtual void OnDownloadOpened(content::DownloadItem* download) OVERRIDE;
+  virtual void OnDownloadDestroyed(content::DownloadItem* download) OVERRIDE;
 
   // Overridden from views::View:
   virtual void Layout() OVERRIDE;