Attempt to fix a renderer crash in NetErrorHelperCore.

chrome/renderer/net/net_error_helper.cc

 // Copyright (c) 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.
 
 #include "chrome/renderer/net/net_error_helper.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/i18n/rtl.h"
@@ skipping 94 matching lines @@
   core_->TrackClick(tracking_id);
 }
 
 void NetErrorHelper::DidStartProvisionalLoad() {
   core_->OnStartLoad(GetFrameType(render_frame()),
                      GetLoadingPageType(render_frame()));
 }
 
 void NetErrorHelper::DidCommitProvisionalLoad(bool is_new_navigation,
                                               bool is_same_page_navigation) {
+  // If this is a "same page" navigation, it's not a real navigation.  There
+  // wasn't a start event for it, either, so just ignore it.
+  if (is_same_page_navigation)
+    return;
+
   // Invalidate weak pointers from old error page controllers. If loading a new
   // error page, the controller has not yet been attached, so this won't affect
   // it.
   weak_controller_delegate_factory_.InvalidateWeakPtrs();
 
   core_->OnCommitLoad(GetFrameType(render_frame()),
                       render_frame()->GetWebFrame()->document().url());
 }
 
 void NetErrorHelper::DidFinishLoad() {
@@ skipping 259 matching lines @@
     const std::string& data) {
   tracking_fetcher_.reset();
 }
 
 #if defined(OS_ANDROID)
 void NetErrorHelper::OnSetOfflinePageInfo(
     OfflinePageStatus offline_page_status) {
   core_->OnSetOfflinePageInfo(offline_page_status);
 }
 #endif  // defined(OS_ANDROID)