Give the main frame a RenderWidget.

ui/views/controls/webview/web_dialog_view.cc

 // 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.
 
 #include "ui/views/controls/webview/web_dialog_view.h"
 
 #include <vector>
 
 #include "base/strings/utf_string_conversions.h"
 #include "content/public/browser/browser_context.h"
@@ skipping 316 matching lines @@
 
 void WebDialogView::BeforeUnloadFired(content::WebContents* tab,
                                       bool proceed,
                                       bool* proceed_to_fire_unload) {
   before_unload_fired_ = true;
   *proceed_to_fire_unload = proceed;
 }
 
 bool WebDialogView::ShouldCreateWebContents(
     content::WebContents* web_contents,
-    int route_id,
-    int main_frame_route_id,
+    int32 route_id,
+    int32 main_frame_route_id,
+    int32 main_frame_widget_route_id,
+    int32 surface_id,
     WindowContainerType window_container_type,
     const std::string& frame_name,
     const GURL& target_url,
     const std::string& partition_id,
     content::SessionStorageNamespace* session_storage_namespace) {
   if (delegate_)
     return delegate_->HandleShouldCreateWebContents();
   return true;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // WebDialogView, private:
 
 void WebDialogView::InitDialog() {
   content::WebContents* web_contents = web_view_->GetWebContents();
   if (web_contents->GetDelegate() == this)
     return;
 
   web_contents->SetDelegate(this);
 
   // Set the delegate. This must be done before loading the page. See
   // the comment above WebDialogUI in its header file for why.
   WebDialogUI::SetDelegate(web_contents, this);
 
   web_view_->LoadInitialURL(GetDialogContentURL());
 }
 
 }  // namespace views