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

chrome/browser/download/download_util.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.
 //
 // Download utility implementation
 
 #include "chrome/browser/download/download_util.h"
 
 #if defined(OS_WIN)
 #include <shobjidl.h>
@@ skipping 644 matching lines @@
     file_value->SetString("progress_status_text",
         GetProgressStatusText(download));
 
     file_value->SetInteger("percent",
         static_cast<int>(download->PercentComplete()));
     file_value->SetInteger("received",
         static_cast<int>(download->received_bytes()));
   } else if (download->IsCancelled()) {
     file_value->SetString("state", "CANCELLED");
   } else if (download->IsComplete()) {
-    if (download->safety_state() == DownloadItem::DANGEROUS) {
+    if (!download->file_exists()) {
+      file_value->SetString("state", "REMOVED");
+    } else if (download->safety_state() == DownloadItem::DANGEROUS) {
       file_value->SetString("state", "DANGEROUS");
     } else {
       file_value->SetString("state", "COMPLETE");
     }
   }
 
   file_value->SetInteger("total",
       static_cast<int>(download->total_bytes()));
 
   return file_value;
@@ skipping 218 matching lines @@
     // Extensions that are not from the gallery are considered dangerous.
     ExtensionService* service = profile->GetExtensionService();
     if (!service ||
         !service->IsDownloadFromGallery(info->url(), info->referrer_url))
       return true;
   }
   return false;
 }
 
 }  // namespace download_util