fix a problem that download dangerous files in a blank page can fail with authentication

content/public/android/java/src/org/chromium/content/browser/ContentViewDownloadDelegate.java

 // Copyright (c) 2012 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.
 
 package org.chromium.content.browser;
 
 /**
  * Interface to be implemented by the embedder to handle file downloads.
  */
 public interface ContentViewDownloadDelegate {
     /**
      * Notify the host application that a file should be downloaded. Replaces
      * onDownloadStart from DownloadListener.
      * @param url The full url to the content that should be downloaded
      * @param userAgent the user agent to be used for the download.
      * @param contentDisposition Content-disposition http header, if
      *                           present.
      * @param mimetype The mimetype of the content reported by the server.
      * @param cookie The cookie
      * @param referer Referer http header.
      * @param contentLength The file size reported by the server.
      */
     void requestHttpGetDownload(String url, String userAgent, String contentDisposition,
             String mimetype, String cookie, String referer, long contentLength);
 
     /**
      * Notify the host application that a download is started.
+     * @param filename File name of the downloaded file.
+     * @param mimeType Mime of the downloaded item.
      */
-    void onDownloadStarted();
-
-    /**
-     * Notify the host application that a download is finished.
-     * @param url The full url to the content that was downloaded.
-     * @param mimetype The mimetype of downloaded file.
-     * @param path Path of the downloaded file.
-     * @param contentLength The file size of the downloaded file (in bytes).
-     * @param successful Whether the download succeeded
-     */
-    void onDownloadCompleted(String url, String mimetype, String path,
-            long contentLength, boolean successful);
+    void onDownloadStarted(String filename, String mimeType);
 
     /**
      * Notify the host application that a download has an extension indicating
      * a dangerous file type.
      * @param filename File name of the downloaded file.
      * @param downloadId The download id.
      */
     void onDangerousDownload(String filename, int downloadId);
 }