Download shelf autohides on showing in shell, just same as regular open

chrome/browser/download/all_download_item_notifier.h

Index: chrome/browser/download/all_download_item_notifier.h
diff --git a/chrome/browser/download/all_download_item_notifier.h b/chrome/browser/download/all_download_item_notifier.h
index c48921422f0a648a9b62708b19ffc433f3f4f0c5..6452da7d6565440648f4ab56912d71fb02a32a50 100644
--- a/chrome/browser/download/all_download_item_notifier.h
+++ b/chrome/browser/download/all_download_item_notifier.h
@@ -50,6 +50,8 @@ class AllDownloadItemNotifier : public content::DownloadManager::Observer,
         content::DownloadManager* manager, content::DownloadItem* item) {}
     virtual void OnDownloadOpened(
         content::DownloadManager* manager, content::DownloadItem* item) {}
+    virtual void OnDownloadShown(
+        content::DownloadManager* manager, content::DownloadItem* item) {}
     virtual void OnDownloadRemoved(
         content::DownloadManager* manager, content::DownloadItem* item) {}
 
@@ -74,6 +76,7 @@ class AllDownloadItemNotifier : public content::DownloadManager::Observer,
   // content::DownloadItem::Observer
   void OnDownloadUpdated(content::DownloadItem* item) override;
   void OnDownloadOpened(content::DownloadItem* item) override;
+  void OnDownloadShown(content::DownloadItem* item) override;
   void OnDownloadRemoved(content::DownloadItem* item) override;
   void OnDownloadDestroyed(content::DownloadItem* item) override;