Add an error page for resources blocked via XSS Auditor.

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

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights
  * reserved.
  * Copyright (C) 2012 Google Inc. 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 114 matching lines @@
   virtual void dispatchWillSubmitForm(HTMLFormElement*) = 0;
 
   virtual void didStartLoading(LoadStartType) = 0;
   virtual void progressEstimateChanged(double progressEstimate) = 0;
   virtual void didStopLoading() = 0;
 
   virtual void loadURLExternally(const ResourceRequest&,
                                  NavigationPolicy,
                                  const String& suggestedName,
                                  bool replacesCurrentHistoryItem) = 0;
+  virtual void loadErrorPage(int reason) = 0;
 
   virtual bool navigateBackForward(int offset) const = 0;
 
   // Another page has accessed the initial empty document of this frame. It is
   // no longer safe to display a provisional URL, since a URL spoof is now
   // possible.
   virtual void didAccessInitialDocument() {}
 
   // This frame has displayed inactive content (such as an image) from an
   // insecure source.  Inactive content cannot spread to other frames.
@@ skipping 187 matching lines @@
   }
 
   // Overwrites the given URL to use an HTML5 embed if possible. An empty URL is
   // returned if the URL is not overriden.
   virtual KURL overrideFlashEmbedWithHTML(const KURL&) { return KURL(); }
 };
 
 }  // namespace blink
 
 #endif  // FrameLoaderClient_h