Make <webview> use out-of-process iframe architecture.

extensions/renderer/resources/guest_view/guest_view.js

 // Copyright 2014 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.
 
 // This module implements a wrapper for a guestview that manages its
 // creation, attaching, and destruction.
 
 var CreateEvent = require('guestViewEvents').CreateEvent;
 var EventBindings = require('event_bindings');
 var GuestViewInternal =
@@ skipping 112 matching lines @@
   // current state.
   var error;
   if (error = errors[action][this.state]) {
     window.console.error(errorPrefix + error);
     return false;
   }
 
   return true;
 };
 
+GuestViewImpl.prototype.setContentWindow = function(contentWindow) {
+  this.contentWindow = contentWindow;
+};
+
 // Internal implementation of attach().
 GuestViewImpl.prototype.attachImpl = function(
     internalInstanceId, viewInstanceId, attachParams, callback) {
   // Check the current state.
   if (!this.checkState('attach')) {
     this.handleCallback(callback);
     return;
   }
 
   // Callback wrapper function to store the contentWindow from the attachGuest()
@@ skipping 174 matching lines @@
       internal, sizeParams, callback));
   internal.performNextAction();
 };
 
 // Returns the contentWindow for this guestview.
 GuestView.prototype.getContentWindow = function() {
   var internal = privates(this).internal;
   return internal.contentWindow;
 };
 
+GuestView.prototype.setContentWindow = function(contentWindow) {
+  var internal = privates(this).internal;
+  return internal.setContentWindow(contentWindow);
+};
+
 // Returns the ID for this guestview.
 GuestView.prototype.getId = function() {
   var internal = privates(this).internal;
   return internal.id;
 };
 
 // Exports
 exports.GuestView = GuestView;