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

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

 /*
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2011 Apple 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 36 matching lines @@
     ContentDispositionInline,
     ContentDispositionAttachment,
     ContentDispositionOther
 } ContentDispositionType;
 
 enum ContentTypeOptionsDisposition {
     ContentTypeOptionsNone,
     ContentTypeOptionsNosniff
 };
 
-enum XFrameOptionsDisposition {
-    XFrameOptionsInvalid,
-    XFrameOptionsDeny,
-    XFrameOptionsSameOrigin,
-    XFrameOptionsAllowAll,
-    XFrameOptionsConflict
-};
-
 // Be sure to update the behavior of XSSAuditor::combineXSSProtectionHeaderAndCSP whenever you change this enum's content or ordering.
 enum ReflectedXSSDisposition {
     ReflectedXSSUnset = 0,
     AllowReflectedXSS,
     ReflectedXSSInvalid,
     FilterReflectedXSS,
     BlockReflectedXSS
 };
 
 using CommaDelimitedHeaderSet = HashSet<String, CaseFoldingHash>;
@@ skipping 39 matching lines @@
 //
 // Note:
 // - This function does not in any way check that the "type/subtype" pair
 //   is well-formed.
 // - OWSes at the head and the tail of the region before the first semicolon
 //   are trimmed.
 PLATFORM_EXPORT AtomicString extractMIMETypeFromMediaType(const AtomicString&);
 PLATFORM_EXPORT String extractCharsetFromMediaType(const String&);
 PLATFORM_EXPORT void findCharsetInMediaType(const String& mediaType, unsigned& charsetPos, unsigned& charsetLen, unsigned start = 0);
 PLATFORM_EXPORT ReflectedXSSDisposition parseXSSProtectionHeader(const String& header, String& failureReason, unsigned& failurePosition, String& reportURL);
-PLATFORM_EXPORT XFrameOptionsDisposition parseXFrameOptionsHeader(const String&);
 PLATFORM_EXPORT CacheControlHeader parseCacheControlDirectives(const AtomicString& cacheControlHeader, const AtomicString& pragmaHeader);
 PLATFORM_EXPORT void parseCommaDelimitedHeader(const String& headerValue, CommaDelimitedHeaderSet&);
 // Returns true on success, otherwise false. The Suborigin argument must be a
 // non-null return argument. |messages| is a list of messages based on any
 // parse warnings or errors. Even if parseSuboriginHeader returns true, there
 // may be Strings in |messages|.
 PLATFORM_EXPORT bool parseSuboriginHeader(const String& header, Suborigin*, WTF::Vector<String>& messages);
 
 PLATFORM_EXPORT ContentTypeOptionsDisposition parseContentTypeOptionsHeader(const String& header);
 
 } // namespace blink
 
 #endif