Avoid a NOT_REACHED() hit when we get an empty 404 page and

content/renderer/render_view.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.
 
 #include "content/renderer/render_view.h"
 
 #include <algorithm>
 #include <cmath>
 #include <string>
 #include <vector>
@@ skipping 2616 matching lines @@
 
   // Display error page, if appropriate.
   int http_status_code = navigation_state->http_status_code();
   if (http_status_code == 404) {
     // On 404s, try a remote search page as a fallback.
     const GURL& frame_url = frame->url();
 
     const GURL& error_page_url = GetAlternateErrorPageURL(frame_url, HTTP_404);
     if (error_page_url.is_valid()) {
       WebURLError original_error;
+      original_error.domain = "http";
+      original_error.reason = 404;
       original_error.unreachableURL = frame_url;
 
       navigation_state->set_alt_error_page_fetcher(
           new AltErrorPageResourceFetcher(
               error_page_url, frame, original_error,
               NewCallback(this, &RenderView::AltErrorPageFinished)));
       return;
     }
   }
 
@@ skipping 1595 matching lines @@
     const webkit_glue::CustomContextMenuContext& custom_context) {
   if (custom_context.is_pepper_menu)
     pepper_delegate_.OnContextMenuClosed(custom_context);
   else
     context_menu_node_.reset();
 }
 
 void RenderView::OnNetworkStateChanged(bool online) {
   WebNetworkStateNotifier::setOnLine(online);
 }