(Re-)introduce AncestorThrottle to handle 'X-Frame-Options'.

third_party/WebKit/Source/platform/network/ResourceError.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2013 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
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 94 matching lines @@
   }
   bool staleCopyInCache() const { return m_staleCopyInCache; }
 
   void setWasIgnoredByHandler(bool ignoredByHandler) {
     m_wasIgnoredByHandler = ignoredByHandler;
   }
   bool wasIgnoredByHandler() const { return m_wasIgnoredByHandler; }
 
   void setIsCacheMiss(bool isCacheMiss) { m_isCacheMiss = isCacheMiss; }
   bool isCacheMiss() const { return m_isCacheMiss; }
+  bool wasBlockedByResponse() const {
+    return m_errorCode == net::ERR_BLOCKED_BY_RESPONSE;
+  }
 
   static bool compare(const ResourceError&, const ResourceError&);
 
  private:
   String m_domain;
   int m_errorCode;
   String m_failingURL;
   String m_localizedDescription;
   bool m_isNull;
   bool m_isCancellation;
@@ skipping 10 matching lines @@
 inline bool operator!=(const ResourceError& a, const ResourceError& b) {
   return !(a == b);
 }
 
 // Pretty printer for gtest. Declared here to avoid ODR violations.
 std::ostream& operator<<(std::ostream&, const ResourceError&);
 
 }  // namespace blink
 
 #endif  // ResourceError_h