Add a comma delimited syntax parser and use it for Accept-CH

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 15 matching lines @@
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef HTTPParsers_h
 #define HTTPParsers_h
 
 #include "platform/PlatformExport.h"
 #include "wtf/Forward.h"
+#include "wtf/HashSet.h"
 #include "wtf/Vector.h"
+#include "wtf/text/StringHash.h"
 
 namespace blink {
 
 typedef enum {
     ContentDispositionNone,
     ContentDispositionInline,
     ContentDispositionAttachment,
     ContentDispositionOther
 } ContentDispositionType;
 
@@ skipping 13 matching lines @@
 
 // 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>;
+
 struct CacheControlHeader {
     bool parsed : 1;
     bool containsNoCache : 1;
     bool containsNoStore : 1;
     bool containsMustRevalidate : 1;
     double maxAge;
 
     CacheControlHeader()
         : parsed(false)
         , containsNoCache(false)
@@ skipping 10 matching lines @@
 PLATFORM_EXPORT bool parseHTTPRefresh(const String& refresh, bool fromHttpEquivMeta, double& delay, String& url);
 PLATFORM_EXPORT double parseDate(const String&);
 PLATFORM_EXPORT String filenameFromHTTPContentDisposition(const String&);
 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 String extractReasonPhraseFromHTTPStatusLine(const String&);
 PLATFORM_EXPORT XFrameOptionsDisposition parseXFrameOptionsHeader(const String&);
 PLATFORM_EXPORT CacheControlHeader parseCacheControlDirectives(const AtomicString& cacheControlHeader, const AtomicString& pragmaHeader);
+PLATFORM_EXPORT void parseCommaDelimitedHeader(const String& headerValue, CommaDelimitedHeaderSet&);
 
 // -1 could be set to one of the return parameters to indicate the value is not specified.
 PLATFORM_EXPORT bool parseRange(const String&, long long& rangeOffset, long long& rangeEnd, long long& rangeSuffixLength);
 
 PLATFORM_EXPORT ContentTypeOptionsDisposition parseContentTypeOptionsHeader(const String& header);
 
 // Parsing Complete HTTP Messages.
 enum HTTPVersion { Unknown, HTTP_1_0, HTTP_1_1 };
 PLATFORM_EXPORT size_t parseHTTPRequestLine(const char* data, size_t length, String& failureReason, String& method, String& url, HTTPVersion&);
 PLATFORM_EXPORT size_t parseHTTPHeader(const char* data, size_t length, String& failureReason, AtomicString& nameStr, AtomicString& valueStr);
 PLATFORM_EXPORT size_t parseHTTPRequestBody(const char* data, size_t length, Vector<unsigned char>& body);
 
 }
 
 #endif