permissionrequest API for guest Download.

chrome/renderer/resources/extensions/web_view_experimental.js

 // Copyright 2013 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.
 
 // Shim extension to provide permission request API (and possibly other future
 // experimental APIs) for <webview> tag.
 // See web_view.js for details.
 //
 // We want to control the permission API feature in <webview> separately from
 // the <webview> feature itself. <webview> is available in stable channel, but
 // permission API would only be available for channels CHANNEL_DEV and
 // CHANNEL_CANARY.
 
 var WebView = require('webView').WebView;
 
 var forEach = require('utils').forEach;
 
 /** @type {Array.<string>} */
-var PERMISSION_TYPES = ['media', 'geolocation', 'pointerLock'];
+var PERMISSION_TYPES = ['download', 'media', 'geolocation', 'pointerLock'];
 
 /** @type {string} */
 var REQUEST_TYPE_NEW_WINDOW = 'newwindow';
 
 /** @type {string} */
 var ERROR_MSG_PERMISSION_ALREADY_DECIDED = '<webview>: ' +
     'Permission has already been decided for this "permissionrequest" event.';
 
 var EXPOSED_PERMISSION_EVENT_ATTRIBS = [
     'lastUnlockedBySelf',
     'permission',
+    'requestMethod',
     'url',
     'userGesture'
 ];
 
 /** @type {string} */
 var ERROR_MSG_NEWWINDOW_ACTION_ALREADY_TAKEN = '<webview>: ' +
     'An action has already been taken for this "newwindow" event.';
 
 /** @type {string} */
 var ERROR_MSG_WEBVIEW_EXPECTED = '<webview> element expected.';
@@ skipping 131 matching lines @@
         window, detail.permission, requestId);
 
     var defaultPrevented = !node.dispatchEvent(evt);
     if (!actionTaken && !defaultPrevented) {
       actionTaken = true;
       // The default action is to discard the window.
       objectNode['-internal-setPermission'](requestId, false);
     }
   });
 };