Detect removed files and reflect the state in chrome://downloads and the download shelf

chrome/browser/ui/webui/downloads_dom_handler.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/ui/webui/downloads_dom_handler.h"
 
 #include <algorithm>
 #include <functional>
 
 #include "base/basictypes.h"
@@ skipping 128 matching lines @@
 }
 
 void DownloadsDOMHandler::HandleGetDownloads(const ListValue* args) {
   std::wstring new_search = UTF16ToWideHack(ExtractStringValue(args));
   if (search_text_.compare(new_search) != 0) {
     search_text_ = new_search;
     ModelChanged();
   } else {
     SendCurrentDownloads();
   }
+
+  for (OrderedDownloads::iterator it = download_items_.begin();
+       it != download_items_.end(); ++it) {
+    if ((*it)->IsComplete() && (*it)->is_path_exists())
+      (*it)->AddObserver(this);

[Paweł Hajdan Jr., 2011/05/10 07:59:46]

This AddObserver logic getting scattered across even more methods can quickly
get harder to follow. How about just observing all downloads? Have you tried
that?

+  }
+  download_manager_->CheckExistingPaths();
 }
 
 void DownloadsDOMHandler::HandleOpenFile(const ListValue* args) {
   DownloadItem* file = GetDownloadByValue(args);
   if (file)
     file->OpenDownload();
 }
 
 void DownloadsDOMHandler::HandleDrag(const ListValue* args) {
   DownloadItem* file = GetDownloadByValue(args);
@@ skipping 81 matching lines @@
   return NULL;
 }
 
 DownloadItem* DownloadsDOMHandler::GetDownloadByValue(const ListValue* args) {
   int id;
   if (ExtractIntegerValue(args, &id)) {
     return GetDownloadById(id);
   }
   return NULL;
 }