Add an error page for resources blocked via XSS Auditor.

third_party/WebKit/Source/core/loader/EmptyClients.h

 /*
  * Copyright (C) 2006 Eric Seidel (eric@webkit.org)
  * Copyright (C) 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 2012 Samsung Electronics. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
@@ skipping 271 matching lines @@
   void dispatchWillSubmitForm(HTMLFormElement*) override;
 
   void didStartLoading(LoadStartType) override {}
   void progressEstimateChanged(double) override {}
   void didStopLoading() override {}
 
   void loadURLExternally(const ResourceRequest&,
                          NavigationPolicy,
                          const String&,
                          bool) override {}
+  void loadErrorPage(int reason) {}
 
   DocumentLoader* createDocumentLoader(LocalFrame*,
                                        const ResourceRequest&,
                                        const SubstituteData&) override;
 
   String userAgent() override { return ""; }
 
   String doNotTrackValue() override { return String(); }
 
   void transitionToCommittedForNewPage() override {}
@@ skipping 122 matching lines @@
   ~EmptyContextMenuClient() override {}
   bool showContextMenu(const ContextMenu*, bool) override { return false; }
   void clearContextMenu() override {}
 };
 
 CORE_EXPORT void fillWithEmptyClients(Page::PageClients&);
 
 }  // namespace blink
 
 #endif  // EmptyClients_h